leandrof/linux
1
0
Fork 0
forked from Minki/linux
Code Issues Pull Requests Packages Projects Releases Wiki Activity
e2459357f6
linux/arch/arm/kernel/unwind.c

553 lines
14 KiB
C
Raw Normal View History

[ARM] 5383/2: unwind: Add core support for ARM stack unwinding This patch adds the main functionality for parsing the stack unwinding information generated by the ARM EABI toolchains. The unwinding information consists of an index with a pair of words per function and a table with unwinding instructions. For more information, see "Exception Handling ABI for the ARM Architecture" at: http://infocenter.arm.com/help/topic/com.arm.doc.subset.swdev.abi/index.html Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-02-16 10:41:36 +00:00
/*
* arch/arm/kernel/unwind.c
*
* Copyright (C) 2008 ARM Limited
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
*
* Stack unwinding support for ARM
*
* An ARM EABI version of gcc is required to generate the unwind
* tables. For information about the structure of the unwind tables,
* see "Exception Handling ABI for the ARM Architecture" at:
*
* http://infocenter.arm.com/help/topic/com.arm.doc.subset.swdev.abi/index.html
*/
ARM: 6140/1: silence a bogus sparse warning in unwind.c The check for compiler which is supposed to miscompile unwind tables clearly has nothing to do with sparse (which does not define necessary macros anyway), so simply silence it. Signed-off-by: Alexander Shishkin <virtuoso@slind.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-05-21 11:32:07 +00:00
#ifndef __CHECKER__
ARM: 5776/1: Check compiler version and EABI support when adding ARM unwind support. ARM unwind is known to compile only with EABI and not-buggy compilers. The problem is not the unwinding information but the -fno-frame-pointer option added as a result of !CONFIG_FRAME_POINTER. Now we check the compiler and raise a #warning in case of wrong compiler. Signed-off-by: Claudio Scordino <claudio@evidence.eu.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-10-30 11:06:05 +00:00
#if !defined (__ARM_EABI__)
#warning Your compiler does not have EABI support.
#warning ARM unwind is known to compile only with EABI compilers.
#warning Change compiler or disable ARM_UNWIND option.
arm, unwind, LLVMLinux: Enable clang to be used for unwinding the stack Patch to prevent warning of a buggy compiler when using clang and the ARM_UNWIND option. Clang defines (at least on the current trunk) GNUC, GNUC_MINOR, and GNUC_PATCHLEVEL to 4, 2, and 1 respectively. This version of GCC gets flagged as buggy, but it isn't actually an issue with clang so the patch will do what it did before unless clang is defined and then it will not report the GCC version as an issue. Signed-off-by: Mark Charlebois <charlebm@gmail.com> Signed-off-by: Behan Webster <behanw@converseincode.com>
2014-02-12 03:26:08 +00:00
#elif (__GNUC__ == 4 && __GNUC_MINOR__ <= 2) && !defined(__clang__)
ARM: 5776/1: Check compiler version and EABI support when adding ARM unwind support. ARM unwind is known to compile only with EABI and not-buggy compilers. The problem is not the unwinding information but the -fno-frame-pointer option added as a result of !CONFIG_FRAME_POINTER. Now we check the compiler and raise a #warning in case of wrong compiler. Signed-off-by: Claudio Scordino <claudio@evidence.eu.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-10-30 11:06:05 +00:00
#warning Your compiler is too buggy; it is known to not compile ARM unwind support.
#warning Change compiler or disable ARM_UNWIND option.
#endif
ARM: 6140/1: silence a bogus sparse warning in unwind.c The check for compiler which is supposed to miscompile unwind tables clearly has nothing to do with sparse (which does not define necessary macros anyway), so simply silence it. Signed-off-by: Alexander Shishkin <virtuoso@slind.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-05-21 11:32:07 +00:00
#endif /* __CHECKER__ */
ARM: 5776/1: Check compiler version and EABI support when adding ARM unwind support. ARM unwind is known to compile only with EABI and not-buggy compilers. The problem is not the unwinding information but the -fno-frame-pointer option added as a result of !CONFIG_FRAME_POINTER. Now we check the compiler and raise a #warning in case of wrong compiler. Signed-off-by: Claudio Scordino <claudio@evidence.eu.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-10-30 11:06:05 +00:00
[ARM] 5383/2: unwind: Add core support for ARM stack unwinding This patch adds the main functionality for parsing the stack unwinding information generated by the ARM EABI toolchains. The unwinding information consists of an index with a pair of words per function and a table with unwinding instructions. For more information, see "Exception Handling ABI for the ARM Architecture" at: http://infocenter.arm.com/help/topic/com.arm.doc.subset.swdev.abi/index.html Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-02-16 10:41:36 +00:00
#include <linux/kernel.h>
#include <linux/init.h>
arm: convert core files from module.h to export.h Many of the core ARM kernel files are not modules, but just including module.h for exporting symbols. Now these files can use the lighter footprint export.h for this role. There are probably lots more, but ARM files of mach-* and plat-* don't get coverage via a simple yesconfig build. They will have to be cleaned up and tested via using their respective configs. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-07-22 14:58:34 +00:00
#include <linux/export.h>
[ARM] 5383/2: unwind: Add core support for ARM stack unwinding This patch adds the main functionality for parsing the stack unwinding information generated by the ARM EABI toolchains. The unwinding information consists of an index with a pair of words per function and a table with unwinding instructions. For more information, see "Exception Handling ABI for the ARM Architecture" at: http://infocenter.arm.com/help/topic/com.arm.doc.subset.swdev.abi/index.html Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-02-16 10:41:36 +00:00
#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/list.h>
#include <asm/stacktrace.h>
#include <asm/traps.h>
#include <asm/unwind.h>
/* Dummy functions to avoid linker complaints */
void __aeabi_unwind_cpp_pr0(void)
{
};
EXPORT_SYMBOL(__aeabi_unwind_cpp_pr0);
void __aeabi_unwind_cpp_pr1(void)
{
};
EXPORT_SYMBOL(__aeabi_unwind_cpp_pr1);
void __aeabi_unwind_cpp_pr2(void)
{
};
EXPORT_SYMBOL(__aeabi_unwind_cpp_pr2);
struct unwind_ctrl_block {
unsigned long vrs[16]; /* virtual register set */
ARM: 7187/1: fix unwinding for XIP kernels The linker places the unwind tables in readonly sections. So when using an XIP kernel these are located in ROM and cannot be modified. For that reason the current approach to convert the relative offsets in the unwind index to absolute addresses early in the boot process doesn't work with XIP. The offsets in the unwind index section are signed 31 bit numbers and the structs are sorted by this offset. So it first has offsets between 0x40000000 and 0x7fffffff (i.e. the negative offsets) and then offsets between 0x00000000 and 0x3fffffff. When seperating these two blocks the numbers are sorted even when interpreting the offsets as unsigned longs. So determine the first non-negative entry once and track that using the new origin pointer. The actual bisection can then use a plain unsigned long comparison. The only thing that makes the new bisection more complicated is that the offsets are relative to their position in the index section, so the key to search needs to be adapted accordingly in each step. Moreover several consts are added to catch future writes and rename the member "addr" of struct unwind_idx to "addr_offset" to better match the new semantic. (This has the additional benefit of breaking eventual users at compile time to make them aware of the change.) In my tests the new algorithm was a tad faster than the original and has the additional upside of not needing the initial conversion and so saves some boot time and it's possible to unwind even earlier. Acked-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Nicolas Pitre <nico@fluxnic.net> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-12-05 08:39:59 +00:00
const unsigned long *insn; /* pointer to the current instructions word */
ARM: 7987/1: ARM : unwinder : Prevent data abort due to stack overflow While unwinding backtrace, stack overflow is possible. This stack overflow can sometimes lead to data abort in system if the area after stack is not mapped to physical memory. To prevent this problem from happening, execute the instructions that can cause a data abort in separate helper functions, where a check for feasibility is made before reading each word from the stack. Signed-off-by: Anurag Aggarwal <a.anurag@samsung.com> Reviewed-by: Dave Martin <Dave.Martin@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2014-02-24 10:17:36 +00:00
unsigned long sp_high; /* highest value of sp allowed */
/*
* 1 : check for stack overflow for each register pop.
* 0 : save overhead if there is plenty of stack remaining.
*/
int check_each_pop;
[ARM] 5383/2: unwind: Add core support for ARM stack unwinding This patch adds the main functionality for parsing the stack unwinding information generated by the ARM EABI toolchains. The unwinding information consists of an index with a pair of words per function and a table with unwinding instructions. For more information, see "Exception Handling ABI for the ARM Architecture" at: http://infocenter.arm.com/help/topic/com.arm.doc.subset.swdev.abi/index.html Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-02-16 10:41:36 +00:00
int entries; /* number of entries left to interpret */
int byte; /* current byte number in the instructions word */
};
enum regs {
Thumb-2: Implementation of the unified start-up and exceptions code This patch implements the ARM/Thumb-2 unified kernel start-up and exception handling code. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2009-07-24 11:32:54 +00:00
#ifdef CONFIG_THUMB2_KERNEL
FP = 7,
#else
[ARM] 5383/2: unwind: Add core support for ARM stack unwinding This patch adds the main functionality for parsing the stack unwinding information generated by the ARM EABI toolchains. The unwinding information consists of an index with a pair of words per function and a table with unwinding instructions. For more information, see "Exception Handling ABI for the ARM Architecture" at: http://infocenter.arm.com/help/topic/com.arm.doc.subset.swdev.abi/index.html Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-02-16 10:41:36 +00:00
FP = 11,
Thumb-2: Implementation of the unified start-up and exceptions code This patch implements the ARM/Thumb-2 unified kernel start-up and exception handling code. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2009-07-24 11:32:54 +00:00
#endif
[ARM] 5383/2: unwind: Add core support for ARM stack unwinding This patch adds the main functionality for parsing the stack unwinding information generated by the ARM EABI toolchains. The unwinding information consists of an index with a pair of words per function and a table with unwinding instructions. For more information, see "Exception Handling ABI for the ARM Architecture" at: http://infocenter.arm.com/help/topic/com.arm.doc.subset.swdev.abi/index.html Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-02-16 10:41:36 +00:00
SP = 13,
LR = 14,
PC = 15
};
ARM: 7187/1: fix unwinding for XIP kernels The linker places the unwind tables in readonly sections. So when using an XIP kernel these are located in ROM and cannot be modified. For that reason the current approach to convert the relative offsets in the unwind index to absolute addresses early in the boot process doesn't work with XIP. The offsets in the unwind index section are signed 31 bit numbers and the structs are sorted by this offset. So it first has offsets between 0x40000000 and 0x7fffffff (i.e. the negative offsets) and then offsets between 0x00000000 and 0x3fffffff. When seperating these two blocks the numbers are sorted even when interpreting the offsets as unsigned longs. So determine the first non-negative entry once and track that using the new origin pointer. The actual bisection can then use a plain unsigned long comparison. The only thing that makes the new bisection more complicated is that the offsets are relative to their position in the index section, so the key to search needs to be adapted accordingly in each step. Moreover several consts are added to catch future writes and rename the member "addr" of struct unwind_idx to "addr_offset" to better match the new semantic. (This has the additional benefit of breaking eventual users at compile time to make them aware of the change.) In my tests the new algorithm was a tad faster than the original and has the additional upside of not needing the initial conversion and so saves some boot time and it's possible to unwind even earlier. Acked-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Nicolas Pitre <nico@fluxnic.net> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-12-05 08:39:59 +00:00
extern const struct unwind_idx __start_unwind_idx[];
static const struct unwind_idx *__origin_unwind_idx;
extern const struct unwind_idx __stop_unwind_idx[];
[ARM] 5383/2: unwind: Add core support for ARM stack unwinding This patch adds the main functionality for parsing the stack unwinding information generated by the ARM EABI toolchains. The unwinding information consists of an index with a pair of words per function and a table with unwinding instructions. For more information, see "Exception Handling ABI for the ARM Architecture" at: http://infocenter.arm.com/help/topic/com.arm.doc.subset.swdev.abi/index.html Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-02-16 10:41:36 +00:00
static DEFINE_SPINLOCK(unwind_lock);
static LIST_HEAD(unwind_tables);
/* Convert a prel31 symbol to an absolute address */
#define prel31_to_addr(ptr) \
({ \
/* sign-extend to 32 bits */ \
long offset = (((long)*(ptr)) << 1) >> 1; \
(unsigned long)(ptr) + offset; \
})
/*
ARM: 7187/1: fix unwinding for XIP kernels The linker places the unwind tables in readonly sections. So when using an XIP kernel these are located in ROM and cannot be modified. For that reason the current approach to convert the relative offsets in the unwind index to absolute addresses early in the boot process doesn't work with XIP. The offsets in the unwind index section are signed 31 bit numbers and the structs are sorted by this offset. So it first has offsets between 0x40000000 and 0x7fffffff (i.e. the negative offsets) and then offsets between 0x00000000 and 0x3fffffff. When seperating these two blocks the numbers are sorted even when interpreting the offsets as unsigned longs. So determine the first non-negative entry once and track that using the new origin pointer. The actual bisection can then use a plain unsigned long comparison. The only thing that makes the new bisection more complicated is that the offsets are relative to their position in the index section, so the key to search needs to be adapted accordingly in each step. Moreover several consts are added to catch future writes and rename the member "addr" of struct unwind_idx to "addr_offset" to better match the new semantic. (This has the additional benefit of breaking eventual users at compile time to make them aware of the change.) In my tests the new algorithm was a tad faster than the original and has the additional upside of not needing the initial conversion and so saves some boot time and it's possible to unwind even earlier. Acked-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Nicolas Pitre <nico@fluxnic.net> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-12-05 08:39:59 +00:00
* Binary search in the unwind index. The entries are
[ARM] 5383/2: unwind: Add core support for ARM stack unwinding This patch adds the main functionality for parsing the stack unwinding information generated by the ARM EABI toolchains. The unwinding information consists of an index with a pair of words per function and a table with unwinding instructions. For more information, see "Exception Handling ABI for the ARM Architecture" at: http://infocenter.arm.com/help/topic/com.arm.doc.subset.swdev.abi/index.html Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-02-16 10:41:36 +00:00
* guaranteed to be sorted in ascending order by the linker.
ARM: 7187/1: fix unwinding for XIP kernels The linker places the unwind tables in readonly sections. So when using an XIP kernel these are located in ROM and cannot be modified. For that reason the current approach to convert the relative offsets in the unwind index to absolute addresses early in the boot process doesn't work with XIP. The offsets in the unwind index section are signed 31 bit numbers and the structs are sorted by this offset. So it first has offsets between 0x40000000 and 0x7fffffff (i.e. the negative offsets) and then offsets between 0x00000000 and 0x3fffffff. When seperating these two blocks the numbers are sorted even when interpreting the offsets as unsigned longs. So determine the first non-negative entry once and track that using the new origin pointer. The actual bisection can then use a plain unsigned long comparison. The only thing that makes the new bisection more complicated is that the offsets are relative to their position in the index section, so the key to search needs to be adapted accordingly in each step. Moreover several consts are added to catch future writes and rename the member "addr" of struct unwind_idx to "addr_offset" to better match the new semantic. (This has the additional benefit of breaking eventual users at compile time to make them aware of the change.) In my tests the new algorithm was a tad faster than the original and has the additional upside of not needing the initial conversion and so saves some boot time and it's possible to unwind even earlier. Acked-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Nicolas Pitre <nico@fluxnic.net> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-12-05 08:39:59 +00:00
*
* start = first entry
* origin = first entry with positive offset (or stop if there is no such entry)
* stop - 1 = last entry
[ARM] 5383/2: unwind: Add core support for ARM stack unwinding This patch adds the main functionality for parsing the stack unwinding information generated by the ARM EABI toolchains. The unwinding information consists of an index with a pair of words per function and a table with unwinding instructions. For more information, see "Exception Handling ABI for the ARM Architecture" at: http://infocenter.arm.com/help/topic/com.arm.doc.subset.swdev.abi/index.html Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-02-16 10:41:36 +00:00
*/
ARM: 7187/1: fix unwinding for XIP kernels The linker places the unwind tables in readonly sections. So when using an XIP kernel these are located in ROM and cannot be modified. For that reason the current approach to convert the relative offsets in the unwind index to absolute addresses early in the boot process doesn't work with XIP. The offsets in the unwind index section are signed 31 bit numbers and the structs are sorted by this offset. So it first has offsets between 0x40000000 and 0x7fffffff (i.e. the negative offsets) and then offsets between 0x00000000 and 0x3fffffff. When seperating these two blocks the numbers are sorted even when interpreting the offsets as unsigned longs. So determine the first non-negative entry once and track that using the new origin pointer. The actual bisection can then use a plain unsigned long comparison. The only thing that makes the new bisection more complicated is that the offsets are relative to their position in the index section, so the key to search needs to be adapted accordingly in each step. Moreover several consts are added to catch future writes and rename the member "addr" of struct unwind_idx to "addr_offset" to better match the new semantic. (This has the additional benefit of breaking eventual users at compile time to make them aware of the change.) In my tests the new algorithm was a tad faster than the original and has the additional upside of not needing the initial conversion and so saves some boot time and it's possible to unwind even earlier. Acked-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Nicolas Pitre <nico@fluxnic.net> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-12-05 08:39:59 +00:00
static const struct unwind_idx *search_index(unsigned long addr,
const struct unwind_idx *start,
const struct unwind_idx *origin,
const struct unwind_idx *stop)
[ARM] 5383/2: unwind: Add core support for ARM stack unwinding This patch adds the main functionality for parsing the stack unwinding information generated by the ARM EABI toolchains. The unwinding information consists of an index with a pair of words per function and a table with unwinding instructions. For more information, see "Exception Handling ABI for the ARM Architecture" at: http://infocenter.arm.com/help/topic/com.arm.doc.subset.swdev.abi/index.html Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-02-16 10:41:36 +00:00
{
ARM: 7187/1: fix unwinding for XIP kernels The linker places the unwind tables in readonly sections. So when using an XIP kernel these are located in ROM and cannot be modified. For that reason the current approach to convert the relative offsets in the unwind index to absolute addresses early in the boot process doesn't work with XIP. The offsets in the unwind index section are signed 31 bit numbers and the structs are sorted by this offset. So it first has offsets between 0x40000000 and 0x7fffffff (i.e. the negative offsets) and then offsets between 0x00000000 and 0x3fffffff. When seperating these two blocks the numbers are sorted even when interpreting the offsets as unsigned longs. So determine the first non-negative entry once and track that using the new origin pointer. The actual bisection can then use a plain unsigned long comparison. The only thing that makes the new bisection more complicated is that the offsets are relative to their position in the index section, so the key to search needs to be adapted accordingly in each step. Moreover several consts are added to catch future writes and rename the member "addr" of struct unwind_idx to "addr_offset" to better match the new semantic. (This has the additional benefit of breaking eventual users at compile time to make them aware of the change.) In my tests the new algorithm was a tad faster than the original and has the additional upside of not needing the initial conversion and so saves some boot time and it's possible to unwind even earlier. Acked-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Nicolas Pitre <nico@fluxnic.net> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-12-05 08:39:59 +00:00
unsigned long addr_prel31;
pr_debug("%s(%08lx, %p, %p, %p)\n",
__func__, addr, start, origin, stop);
/*
* only search in the section with the matching sign. This way the
* prel31 numbers can be compared as unsigned longs.
*/
if (addr < (unsigned long)start)
/* negative offsets: [start; origin) */
stop = origin;
else
/* positive offsets: [origin; stop) */
start = origin;
/* prel31 for address relavive to start */
addr_prel31 = (addr - (unsigned long)start) & 0x7fffffff;
[ARM] 5383/2: unwind: Add core support for ARM stack unwinding This patch adds the main functionality for parsing the stack unwinding information generated by the ARM EABI toolchains. The unwinding information consists of an index with a pair of words per function and a table with unwinding instructions. For more information, see "Exception Handling ABI for the ARM Architecture" at: http://infocenter.arm.com/help/topic/com.arm.doc.subset.swdev.abi/index.html Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-02-16 10:41:36 +00:00
ARM: 7187/1: fix unwinding for XIP kernels The linker places the unwind tables in readonly sections. So when using an XIP kernel these are located in ROM and cannot be modified. For that reason the current approach to convert the relative offsets in the unwind index to absolute addresses early in the boot process doesn't work with XIP. The offsets in the unwind index section are signed 31 bit numbers and the structs are sorted by this offset. So it first has offsets between 0x40000000 and 0x7fffffff (i.e. the negative offsets) and then offsets between 0x00000000 and 0x3fffffff. When seperating these two blocks the numbers are sorted even when interpreting the offsets as unsigned longs. So determine the first non-negative entry once and track that using the new origin pointer. The actual bisection can then use a plain unsigned long comparison. The only thing that makes the new bisection more complicated is that the offsets are relative to their position in the index section, so the key to search needs to be adapted accordingly in each step. Moreover several consts are added to catch future writes and rename the member "addr" of struct unwind_idx to "addr_offset" to better match the new semantic. (This has the additional benefit of breaking eventual users at compile time to make them aware of the change.) In my tests the new algorithm was a tad faster than the original and has the additional upside of not needing the initial conversion and so saves some boot time and it's possible to unwind even earlier. Acked-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Nicolas Pitre <nico@fluxnic.net> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-12-05 08:39:59 +00:00
while (start < stop - 1) {
const struct unwind_idx *mid = start + ((stop - start) >> 1);
/*
* As addr_prel31 is relative to start an offset is needed to
* make it relative to mid.
*/
if (addr_prel31 - ((unsigned long)mid - (unsigned long)start) <
mid->addr_offset)
stop = mid;
else {
/* keep addr_prel31 relative to start */
addr_prel31 -= ((unsigned long)mid -
(unsigned long)start);
start = mid;
}
}
if (likely(start->addr_offset <= addr_prel31))
return start;
else {
[ARM] 5383/2: unwind: Add core support for ARM stack unwinding This patch adds the main functionality for parsing the stack unwinding information generated by the ARM EABI toolchains. The unwinding information consists of an index with a pair of words per function and a table with unwinding instructions. For more information, see "Exception Handling ABI for the ARM Architecture" at: http://infocenter.arm.com/help/topic/com.arm.doc.subset.swdev.abi/index.html Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-02-16 10:41:36 +00:00
pr_warning("unwind: Unknown symbol address %08lx\n", addr);
return NULL;
ARM: 7187/1: fix unwinding for XIP kernels The linker places the unwind tables in readonly sections. So when using an XIP kernel these are located in ROM and cannot be modified. For that reason the current approach to convert the relative offsets in the unwind index to absolute addresses early in the boot process doesn't work with XIP. The offsets in the unwind index section are signed 31 bit numbers and the structs are sorted by this offset. So it first has offsets between 0x40000000 and 0x7fffffff (i.e. the negative offsets) and then offsets between 0x00000000 and 0x3fffffff. When seperating these two blocks the numbers are sorted even when interpreting the offsets as unsigned longs. So determine the first non-negative entry once and track that using the new origin pointer. The actual bisection can then use a plain unsigned long comparison. The only thing that makes the new bisection more complicated is that the offsets are relative to their position in the index section, so the key to search needs to be adapted accordingly in each step. Moreover several consts are added to catch future writes and rename the member "addr" of struct unwind_idx to "addr_offset" to better match the new semantic. (This has the additional benefit of breaking eventual users at compile time to make them aware of the change.) In my tests the new algorithm was a tad faster than the original and has the additional upside of not needing the initial conversion and so saves some boot time and it's possible to unwind even earlier. Acked-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Nicolas Pitre <nico@fluxnic.net> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-12-05 08:39:59 +00:00
}
}
[ARM] 5383/2: unwind: Add core support for ARM stack unwinding This patch adds the main functionality for parsing the stack unwinding information generated by the ARM EABI toolchains. The unwinding information consists of an index with a pair of words per function and a table with unwinding instructions. For more information, see "Exception Handling ABI for the ARM Architecture" at: http://infocenter.arm.com/help/topic/com.arm.doc.subset.swdev.abi/index.html Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-02-16 10:41:36 +00:00
ARM: 7187/1: fix unwinding for XIP kernels The linker places the unwind tables in readonly sections. So when using an XIP kernel these are located in ROM and cannot be modified. For that reason the current approach to convert the relative offsets in the unwind index to absolute addresses early in the boot process doesn't work with XIP. The offsets in the unwind index section are signed 31 bit numbers and the structs are sorted by this offset. So it first has offsets between 0x40000000 and 0x7fffffff (i.e. the negative offsets) and then offsets between 0x00000000 and 0x3fffffff. When seperating these two blocks the numbers are sorted even when interpreting the offsets as unsigned longs. So determine the first non-negative entry once and track that using the new origin pointer. The actual bisection can then use a plain unsigned long comparison. The only thing that makes the new bisection more complicated is that the offsets are relative to their position in the index section, so the key to search needs to be adapted accordingly in each step. Moreover several consts are added to catch future writes and rename the member "addr" of struct unwind_idx to "addr_offset" to better match the new semantic. (This has the additional benefit of breaking eventual users at compile time to make them aware of the change.) In my tests the new algorithm was a tad faster than the original and has the additional upside of not needing the initial conversion and so saves some boot time and it's possible to unwind even earlier. Acked-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Nicolas Pitre <nico@fluxnic.net> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-12-05 08:39:59 +00:00
static const struct unwind_idx *unwind_find_origin(
const struct unwind_idx *start, const struct unwind_idx *stop)
{
pr_debug("%s(%p, %p)\n", __func__, start, stop);
ARM: unwinder: fix bisection to find origin in .idx section The bisection implemented in unwind_find_origin() stopped to early. If there is only a single entry left to check the original code just took the end point as origin which might be wrong. This was introduced in commit de66a979012d ("ARM: 7187/1: fix unwinding for XIP kernels"). Reported-and-tested-by: Nick Bowler <nbowler@elliptictech.com> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-12-15 20:47:56 +00:00
while (start < stop) {
ARM: 7187/1: fix unwinding for XIP kernels The linker places the unwind tables in readonly sections. So when using an XIP kernel these are located in ROM and cannot be modified. For that reason the current approach to convert the relative offsets in the unwind index to absolute addresses early in the boot process doesn't work with XIP. The offsets in the unwind index section are signed 31 bit numbers and the structs are sorted by this offset. So it first has offsets between 0x40000000 and 0x7fffffff (i.e. the negative offsets) and then offsets between 0x00000000 and 0x3fffffff. When seperating these two blocks the numbers are sorted even when interpreting the offsets as unsigned longs. So determine the first non-negative entry once and track that using the new origin pointer. The actual bisection can then use a plain unsigned long comparison. The only thing that makes the new bisection more complicated is that the offsets are relative to their position in the index section, so the key to search needs to be adapted accordingly in each step. Moreover several consts are added to catch future writes and rename the member "addr" of struct unwind_idx to "addr_offset" to better match the new semantic. (This has the additional benefit of breaking eventual users at compile time to make them aware of the change.) In my tests the new algorithm was a tad faster than the original and has the additional upside of not needing the initial conversion and so saves some boot time and it's possible to unwind even earlier. Acked-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Nicolas Pitre <nico@fluxnic.net> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-12-05 08:39:59 +00:00
const struct unwind_idx *mid = start + ((stop - start) >> 1);
[ARM] 5383/2: unwind: Add core support for ARM stack unwinding This patch adds the main functionality for parsing the stack unwinding information generated by the ARM EABI toolchains. The unwinding information consists of an index with a pair of words per function and a table with unwinding instructions. For more information, see "Exception Handling ABI for the ARM Architecture" at: http://infocenter.arm.com/help/topic/com.arm.doc.subset.swdev.abi/index.html Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-02-16 10:41:36 +00:00
ARM: 7187/1: fix unwinding for XIP kernels The linker places the unwind tables in readonly sections. So when using an XIP kernel these are located in ROM and cannot be modified. For that reason the current approach to convert the relative offsets in the unwind index to absolute addresses early in the boot process doesn't work with XIP. The offsets in the unwind index section are signed 31 bit numbers and the structs are sorted by this offset. So it first has offsets between 0x40000000 and 0x7fffffff (i.e. the negative offsets) and then offsets between 0x00000000 and 0x3fffffff. When seperating these two blocks the numbers are sorted even when interpreting the offsets as unsigned longs. So determine the first non-negative entry once and track that using the new origin pointer. The actual bisection can then use a plain unsigned long comparison. The only thing that makes the new bisection more complicated is that the offsets are relative to their position in the index section, so the key to search needs to be adapted accordingly in each step. Moreover several consts are added to catch future writes and rename the member "addr" of struct unwind_idx to "addr_offset" to better match the new semantic. (This has the additional benefit of breaking eventual users at compile time to make them aware of the change.) In my tests the new algorithm was a tad faster than the original and has the additional upside of not needing the initial conversion and so saves some boot time and it's possible to unwind even earlier. Acked-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Nicolas Pitre <nico@fluxnic.net> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-12-05 08:39:59 +00:00
if (mid->addr_offset >= 0x40000000)
/* negative offset */
ARM: unwinder: fix bisection to find origin in .idx section The bisection implemented in unwind_find_origin() stopped to early. If there is only a single entry left to check the original code just took the end point as origin which might be wrong. This was introduced in commit de66a979012d ("ARM: 7187/1: fix unwinding for XIP kernels"). Reported-and-tested-by: Nick Bowler <nbowler@elliptictech.com> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-12-15 20:47:56 +00:00
start = mid + 1;
[ARM] 5383/2: unwind: Add core support for ARM stack unwinding This patch adds the main functionality for parsing the stack unwinding information generated by the ARM EABI toolchains. The unwinding information consists of an index with a pair of words per function and a table with unwinding instructions. For more information, see "Exception Handling ABI for the ARM Architecture" at: http://infocenter.arm.com/help/topic/com.arm.doc.subset.swdev.abi/index.html Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-02-16 10:41:36 +00:00
else
ARM: 7187/1: fix unwinding for XIP kernels The linker places the unwind tables in readonly sections. So when using an XIP kernel these are located in ROM and cannot be modified. For that reason the current approach to convert the relative offsets in the unwind index to absolute addresses early in the boot process doesn't work with XIP. The offsets in the unwind index section are signed 31 bit numbers and the structs are sorted by this offset. So it first has offsets between 0x40000000 and 0x7fffffff (i.e. the negative offsets) and then offsets between 0x00000000 and 0x3fffffff. When seperating these two blocks the numbers are sorted even when interpreting the offsets as unsigned longs. So determine the first non-negative entry once and track that using the new origin pointer. The actual bisection can then use a plain unsigned long comparison. The only thing that makes the new bisection more complicated is that the offsets are relative to their position in the index section, so the key to search needs to be adapted accordingly in each step. Moreover several consts are added to catch future writes and rename the member "addr" of struct unwind_idx to "addr_offset" to better match the new semantic. (This has the additional benefit of breaking eventual users at compile time to make them aware of the change.) In my tests the new algorithm was a tad faster than the original and has the additional upside of not needing the initial conversion and so saves some boot time and it's possible to unwind even earlier. Acked-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Nicolas Pitre <nico@fluxnic.net> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-12-05 08:39:59 +00:00
/* positive offset */
stop = mid;
[ARM] 5383/2: unwind: Add core support for ARM stack unwinding This patch adds the main functionality for parsing the stack unwinding information generated by the ARM EABI toolchains. The unwinding information consists of an index with a pair of words per function and a table with unwinding instructions. For more information, see "Exception Handling ABI for the ARM Architecture" at: http://infocenter.arm.com/help/topic/com.arm.doc.subset.swdev.abi/index.html Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-02-16 10:41:36 +00:00
}
ARM: 7187/1: fix unwinding for XIP kernels The linker places the unwind tables in readonly sections. So when using an XIP kernel these are located in ROM and cannot be modified. For that reason the current approach to convert the relative offsets in the unwind index to absolute addresses early in the boot process doesn't work with XIP. The offsets in the unwind index section are signed 31 bit numbers and the structs are sorted by this offset. So it first has offsets between 0x40000000 and 0x7fffffff (i.e. the negative offsets) and then offsets between 0x00000000 and 0x3fffffff. When seperating these two blocks the numbers are sorted even when interpreting the offsets as unsigned longs. So determine the first non-negative entry once and track that using the new origin pointer. The actual bisection can then use a plain unsigned long comparison. The only thing that makes the new bisection more complicated is that the offsets are relative to their position in the index section, so the key to search needs to be adapted accordingly in each step. Moreover several consts are added to catch future writes and rename the member "addr" of struct unwind_idx to "addr_offset" to better match the new semantic. (This has the additional benefit of breaking eventual users at compile time to make them aware of the change.) In my tests the new algorithm was a tad faster than the original and has the additional upside of not needing the initial conversion and so saves some boot time and it's possible to unwind even earlier. Acked-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Nicolas Pitre <nico@fluxnic.net> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-12-05 08:39:59 +00:00
pr_debug("%s -> %p\n", __func__, stop);
return stop;
[ARM] 5383/2: unwind: Add core support for ARM stack unwinding This patch adds the main functionality for parsing the stack unwinding information generated by the ARM EABI toolchains. The unwinding information consists of an index with a pair of words per function and a table with unwinding instructions. For more information, see "Exception Handling ABI for the ARM Architecture" at: http://infocenter.arm.com/help/topic/com.arm.doc.subset.swdev.abi/index.html Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-02-16 10:41:36 +00:00
}
ARM: 7187/1: fix unwinding for XIP kernels The linker places the unwind tables in readonly sections. So when using an XIP kernel these are located in ROM and cannot be modified. For that reason the current approach to convert the relative offsets in the unwind index to absolute addresses early in the boot process doesn't work with XIP. The offsets in the unwind index section are signed 31 bit numbers and the structs are sorted by this offset. So it first has offsets between 0x40000000 and 0x7fffffff (i.e. the negative offsets) and then offsets between 0x00000000 and 0x3fffffff. When seperating these two blocks the numbers are sorted even when interpreting the offsets as unsigned longs. So determine the first non-negative entry once and track that using the new origin pointer. The actual bisection can then use a plain unsigned long comparison. The only thing that makes the new bisection more complicated is that the offsets are relative to their position in the index section, so the key to search needs to be adapted accordingly in each step. Moreover several consts are added to catch future writes and rename the member "addr" of struct unwind_idx to "addr_offset" to better match the new semantic. (This has the additional benefit of breaking eventual users at compile time to make them aware of the change.) In my tests the new algorithm was a tad faster than the original and has the additional upside of not needing the initial conversion and so saves some boot time and it's possible to unwind even earlier. Acked-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Nicolas Pitre <nico@fluxnic.net> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-12-05 08:39:59 +00:00
static const struct unwind_idx *unwind_find_idx(unsigned long addr)
[ARM] 5383/2: unwind: Add core support for ARM stack unwinding This patch adds the main functionality for parsing the stack unwinding information generated by the ARM EABI toolchains. The unwinding information consists of an index with a pair of words per function and a table with unwinding instructions. For more information, see "Exception Handling ABI for the ARM Architecture" at: http://infocenter.arm.com/help/topic/com.arm.doc.subset.swdev.abi/index.html Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-02-16 10:41:36 +00:00
{
ARM: 7187/1: fix unwinding for XIP kernels The linker places the unwind tables in readonly sections. So when using an XIP kernel these are located in ROM and cannot be modified. For that reason the current approach to convert the relative offsets in the unwind index to absolute addresses early in the boot process doesn't work with XIP. The offsets in the unwind index section are signed 31 bit numbers and the structs are sorted by this offset. So it first has offsets between 0x40000000 and 0x7fffffff (i.e. the negative offsets) and then offsets between 0x00000000 and 0x3fffffff. When seperating these two blocks the numbers are sorted even when interpreting the offsets as unsigned longs. So determine the first non-negative entry once and track that using the new origin pointer. The actual bisection can then use a plain unsigned long comparison. The only thing that makes the new bisection more complicated is that the offsets are relative to their position in the index section, so the key to search needs to be adapted accordingly in each step. Moreover several consts are added to catch future writes and rename the member "addr" of struct unwind_idx to "addr_offset" to better match the new semantic. (This has the additional benefit of breaking eventual users at compile time to make them aware of the change.) In my tests the new algorithm was a tad faster than the original and has the additional upside of not needing the initial conversion and so saves some boot time and it's possible to unwind even earlier. Acked-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Nicolas Pitre <nico@fluxnic.net> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-12-05 08:39:59 +00:00
const struct unwind_idx *idx = NULL;
[ARM] 5383/2: unwind: Add core support for ARM stack unwinding This patch adds the main functionality for parsing the stack unwinding information generated by the ARM EABI toolchains. The unwinding information consists of an index with a pair of words per function and a table with unwinding instructions. For more information, see "Exception Handling ABI for the ARM Architecture" at: http://infocenter.arm.com/help/topic/com.arm.doc.subset.swdev.abi/index.html Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-02-16 10:41:36 +00:00
unsigned long flags;
pr_debug("%s(%08lx)\n", __func__, addr);
ARM: 7187/1: fix unwinding for XIP kernels The linker places the unwind tables in readonly sections. So when using an XIP kernel these are located in ROM and cannot be modified. For that reason the current approach to convert the relative offsets in the unwind index to absolute addresses early in the boot process doesn't work with XIP. The offsets in the unwind index section are signed 31 bit numbers and the structs are sorted by this offset. So it first has offsets between 0x40000000 and 0x7fffffff (i.e. the negative offsets) and then offsets between 0x00000000 and 0x3fffffff. When seperating these two blocks the numbers are sorted even when interpreting the offsets as unsigned longs. So determine the first non-negative entry once and track that using the new origin pointer. The actual bisection can then use a plain unsigned long comparison. The only thing that makes the new bisection more complicated is that the offsets are relative to their position in the index section, so the key to search needs to be adapted accordingly in each step. Moreover several consts are added to catch future writes and rename the member "addr" of struct unwind_idx to "addr_offset" to better match the new semantic. (This has the additional benefit of breaking eventual users at compile time to make them aware of the change.) In my tests the new algorithm was a tad faster than the original and has the additional upside of not needing the initial conversion and so saves some boot time and it's possible to unwind even earlier. Acked-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Nicolas Pitre <nico@fluxnic.net> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-12-05 08:39:59 +00:00
if (core_kernel_text(addr)) {
if (unlikely(!__origin_unwind_idx))
__origin_unwind_idx =
unwind_find_origin(__start_unwind_idx,
__stop_unwind_idx);
[ARM] 5383/2: unwind: Add core support for ARM stack unwinding This patch adds the main functionality for parsing the stack unwinding information generated by the ARM EABI toolchains. The unwinding information consists of an index with a pair of words per function and a table with unwinding instructions. For more information, see "Exception Handling ABI for the ARM Architecture" at: http://infocenter.arm.com/help/topic/com.arm.doc.subset.swdev.abi/index.html Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-02-16 10:41:36 +00:00
/* main unwind table */
idx = search_index(addr, __start_unwind_idx,
ARM: 7187/1: fix unwinding for XIP kernels The linker places the unwind tables in readonly sections. So when using an XIP kernel these are located in ROM and cannot be modified. For that reason the current approach to convert the relative offsets in the unwind index to absolute addresses early in the boot process doesn't work with XIP. The offsets in the unwind index section are signed 31 bit numbers and the structs are sorted by this offset. So it first has offsets between 0x40000000 and 0x7fffffff (i.e. the negative offsets) and then offsets between 0x00000000 and 0x3fffffff. When seperating these two blocks the numbers are sorted even when interpreting the offsets as unsigned longs. So determine the first non-negative entry once and track that using the new origin pointer. The actual bisection can then use a plain unsigned long comparison. The only thing that makes the new bisection more complicated is that the offsets are relative to their position in the index section, so the key to search needs to be adapted accordingly in each step. Moreover several consts are added to catch future writes and rename the member "addr" of struct unwind_idx to "addr_offset" to better match the new semantic. (This has the additional benefit of breaking eventual users at compile time to make them aware of the change.) In my tests the new algorithm was a tad faster than the original and has the additional upside of not needing the initial conversion and so saves some boot time and it's possible to unwind even earlier. Acked-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Nicolas Pitre <nico@fluxnic.net> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-12-05 08:39:59 +00:00
__origin_unwind_idx,
__stop_unwind_idx);
} else {
[ARM] 5383/2: unwind: Add core support for ARM stack unwinding This patch adds the main functionality for parsing the stack unwinding information generated by the ARM EABI toolchains. The unwinding information consists of an index with a pair of words per function and a table with unwinding instructions. For more information, see "Exception Handling ABI for the ARM Architecture" at: http://infocenter.arm.com/help/topic/com.arm.doc.subset.swdev.abi/index.html Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-02-16 10:41:36 +00:00
/* module unwind tables */
struct unwind_table *table;
spin_lock_irqsave(&unwind_lock, flags);
list_for_each_entry(table, &unwind_tables, list) {
if (addr >= table->begin_addr &&
addr < table->end_addr) {
idx = search_index(addr, table->start,
ARM: 7187/1: fix unwinding for XIP kernels The linker places the unwind tables in readonly sections. So when using an XIP kernel these are located in ROM and cannot be modified. For that reason the current approach to convert the relative offsets in the unwind index to absolute addresses early in the boot process doesn't work with XIP. The offsets in the unwind index section are signed 31 bit numbers and the structs are sorted by this offset. So it first has offsets between 0x40000000 and 0x7fffffff (i.e. the negative offsets) and then offsets between 0x00000000 and 0x3fffffff. When seperating these two blocks the numbers are sorted even when interpreting the offsets as unsigned longs. So determine the first non-negative entry once and track that using the new origin pointer. The actual bisection can then use a plain unsigned long comparison. The only thing that makes the new bisection more complicated is that the offsets are relative to their position in the index section, so the key to search needs to be adapted accordingly in each step. Moreover several consts are added to catch future writes and rename the member "addr" of struct unwind_idx to "addr_offset" to better match the new semantic. (This has the additional benefit of breaking eventual users at compile time to make them aware of the change.) In my tests the new algorithm was a tad faster than the original and has the additional upside of not needing the initial conversion and so saves some boot time and it's possible to unwind even earlier. Acked-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Nicolas Pitre <nico@fluxnic.net> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-12-05 08:39:59 +00:00
table->origin,
table->stop);
ARM: 6341/1: unwind - optimise linked-list searches for modules With several sections per module, and dozens of modules, the searches down the linked list of sections would dominate the lookup time, dwarfing any savings from the binary search within the section. A simple move-to-front optimisation exploits the commonality of the code paths taken, and in simple real-world tests reduces the number of steps in the search to barely more than 1. Signed-off-by: Phil Carmody <ext-phil.2.carmody@nokia.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-08-19 14:20:37 +00:00
/* Move-to-front to exploit common traces */
list_move(&table->list, &unwind_tables);
[ARM] 5383/2: unwind: Add core support for ARM stack unwinding This patch adds the main functionality for parsing the stack unwinding information generated by the ARM EABI toolchains. The unwinding information consists of an index with a pair of words per function and a table with unwinding instructions. For more information, see "Exception Handling ABI for the ARM Architecture" at: http://infocenter.arm.com/help/topic/com.arm.doc.subset.swdev.abi/index.html Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-02-16 10:41:36 +00:00
break;
}
}
spin_unlock_irqrestore(&unwind_lock, flags);
}
pr_debug("%s: idx = %p\n", __func__, idx);
return idx;
}
static unsigned long unwind_get_byte(struct unwind_ctrl_block *ctrl)
{
unsigned long ret;
if (ctrl->entries <= 0) {
pr_warning("unwind: Corrupt unwind table\n");
return 0;
}
ret = (*ctrl->insn >> (ctrl->byte * 8)) & 0xff;
if (ctrl->byte == 0) {
ctrl->insn++;
ctrl->entries--;
ctrl->byte = 3;
} else
ctrl->byte--;
return ret;
}
ARM: 7987/1: ARM : unwinder : Prevent data abort due to stack overflow While unwinding backtrace, stack overflow is possible. This stack overflow can sometimes lead to data abort in system if the area after stack is not mapped to physical memory. To prevent this problem from happening, execute the instructions that can cause a data abort in separate helper functions, where a check for feasibility is made before reading each word from the stack. Signed-off-by: Anurag Aggarwal <a.anurag@samsung.com> Reviewed-by: Dave Martin <Dave.Martin@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2014-02-24 10:17:36 +00:00
/* Before poping a register check whether it is feasible or not */
static int unwind_pop_register(struct unwind_ctrl_block *ctrl,
unsigned long **vsp, unsigned int reg)
{
if (unlikely(ctrl->check_each_pop))
if (*vsp >= (unsigned long *)ctrl->sp_high)
return -URC_FAILURE;
ctrl->vrs[reg] = *(*vsp)++;
return URC_OK;
}
/* Helper functions to execute the instructions */
static int unwind_exec_pop_subset_r4_to_r13(struct unwind_ctrl_block *ctrl,
unsigned long mask)
{
unsigned long *vsp = (unsigned long *)ctrl->vrs[SP];
int load_sp, reg = 4;
load_sp = mask & (1 << (13 - 4));
while (mask) {
if (mask & 1)
if (unwind_pop_register(ctrl, &vsp, reg))
return -URC_FAILURE;
mask >>= 1;
reg++;
}
if (!load_sp)
ctrl->vrs[SP] = (unsigned long)vsp;
return URC_OK;
}
static int unwind_exec_pop_r4_to_rN(struct unwind_ctrl_block *ctrl,
unsigned long insn)
{
unsigned long *vsp = (unsigned long *)ctrl->vrs[SP];
int reg;
/* pop R4-R[4+bbb] */
for (reg = 4; reg <= 4 + (insn & 7); reg++)
if (unwind_pop_register(ctrl, &vsp, reg))
return -URC_FAILURE;
ARM: 8052/1: unwind: Fix handling of "Pop r4-r[4+nnn],r14" opcode The arm EABI states that unwind opcode 10100nnn means pop register r4-4[4+nnn],aditionally there is a similar unwind opcode: 10101nnn which means the same thing plus popping r14. Those two cases are handled by the unwind_exec_pop_r4_to_rN function which checks whether the 4th bit is set and does r14 popping. However, up until now it has been checking whether the 8th bit was set (mask & 0x80) instead of the 4th (mask & 0x8), a simple to make typo but this meant that we were always popping r14 even if we had the former opcode. This patch changes the mask so that the 2 unwind opcodes are being handled correctly. Signed-off-by: Nikolay Borisov <Nikolay.Borisov@arm.com> Reviewed-by: Anurag Aggarwal <anurag19aggarwal@gmail.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2014-05-08 14:54:26 +00:00
if (insn & 0x8)
ARM: 7987/1: ARM : unwinder : Prevent data abort due to stack overflow While unwinding backtrace, stack overflow is possible. This stack overflow can sometimes lead to data abort in system if the area after stack is not mapped to physical memory. To prevent this problem from happening, execute the instructions that can cause a data abort in separate helper functions, where a check for feasibility is made before reading each word from the stack. Signed-off-by: Anurag Aggarwal <a.anurag@samsung.com> Reviewed-by: Dave Martin <Dave.Martin@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2014-02-24 10:17:36 +00:00
if (unwind_pop_register(ctrl, &vsp, 14))
return -URC_FAILURE;
ctrl->vrs[SP] = (unsigned long)vsp;
return URC_OK;
}
static int unwind_exec_pop_subset_r0_to_r3(struct unwind_ctrl_block *ctrl,
unsigned long mask)
{
unsigned long *vsp = (unsigned long *)ctrl->vrs[SP];
int reg = 0;
/* pop R0-R3 according to mask */
while (mask) {
if (mask & 1)
if (unwind_pop_register(ctrl, &vsp, reg))
return -URC_FAILURE;
mask >>= 1;
reg++;
}
ctrl->vrs[SP] = (unsigned long)vsp;
return URC_OK;
}
[ARM] 5383/2: unwind: Add core support for ARM stack unwinding This patch adds the main functionality for parsing the stack unwinding information generated by the ARM EABI toolchains. The unwinding information consists of an index with a pair of words per function and a table with unwinding instructions. For more information, see "Exception Handling ABI for the ARM Architecture" at: http://infocenter.arm.com/help/topic/com.arm.doc.subset.swdev.abi/index.html Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-02-16 10:41:36 +00:00
/*
* Execute the current unwind instruction.
*/
static int unwind_exec_insn(struct unwind_ctrl_block *ctrl)
{
unsigned long insn = unwind_get_byte(ctrl);
ARM: 7987/1: ARM : unwinder : Prevent data abort due to stack overflow While unwinding backtrace, stack overflow is possible. This stack overflow can sometimes lead to data abort in system if the area after stack is not mapped to physical memory. To prevent this problem from happening, execute the instructions that can cause a data abort in separate helper functions, where a check for feasibility is made before reading each word from the stack. Signed-off-by: Anurag Aggarwal <a.anurag@samsung.com> Reviewed-by: Dave Martin <Dave.Martin@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2014-02-24 10:17:36 +00:00
int ret = URC_OK;
[ARM] 5383/2: unwind: Add core support for ARM stack unwinding This patch adds the main functionality for parsing the stack unwinding information generated by the ARM EABI toolchains. The unwinding information consists of an index with a pair of words per function and a table with unwinding instructions. For more information, see "Exception Handling ABI for the ARM Architecture" at: http://infocenter.arm.com/help/topic/com.arm.doc.subset.swdev.abi/index.html Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-02-16 10:41:36 +00:00
pr_debug("%s: insn = %08lx\n", __func__, insn);
if ((insn & 0xc0) == 0x00)
ctrl->vrs[SP] += ((insn & 0x3f) << 2) + 4;
else if ((insn & 0xc0) == 0x40)
ctrl->vrs[SP] -= ((insn & 0x3f) << 2) + 4;
else if ((insn & 0xf0) == 0x80) {
unsigned long mask;
insn = (insn << 8) | unwind_get_byte(ctrl);
mask = insn & 0x0fff;
if (mask == 0) {
pr_warning("unwind: 'Refuse to unwind' instruction %04lx\n",
insn);
return -URC_FAILURE;
}
ARM: 7987/1: ARM : unwinder : Prevent data abort due to stack overflow While unwinding backtrace, stack overflow is possible. This stack overflow can sometimes lead to data abort in system if the area after stack is not mapped to physical memory. To prevent this problem from happening, execute the instructions that can cause a data abort in separate helper functions, where a check for feasibility is made before reading each word from the stack. Signed-off-by: Anurag Aggarwal <a.anurag@samsung.com> Reviewed-by: Dave Martin <Dave.Martin@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2014-02-24 10:17:36 +00:00
ret = unwind_exec_pop_subset_r4_to_r13(ctrl, mask);
if (ret)
goto error;
[ARM] 5383/2: unwind: Add core support for ARM stack unwinding This patch adds the main functionality for parsing the stack unwinding information generated by the ARM EABI toolchains. The unwinding information consists of an index with a pair of words per function and a table with unwinding instructions. For more information, see "Exception Handling ABI for the ARM Architecture" at: http://infocenter.arm.com/help/topic/com.arm.doc.subset.swdev.abi/index.html Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-02-16 10:41:36 +00:00
} else if ((insn & 0xf0) == 0x90 &&
(insn & 0x0d) != 0x0d)
ctrl->vrs[SP] = ctrl->vrs[insn & 0x0f];
else if ((insn & 0xf0) == 0xa0) {
ARM: 7987/1: ARM : unwinder : Prevent data abort due to stack overflow While unwinding backtrace, stack overflow is possible. This stack overflow can sometimes lead to data abort in system if the area after stack is not mapped to physical memory. To prevent this problem from happening, execute the instructions that can cause a data abort in separate helper functions, where a check for feasibility is made before reading each word from the stack. Signed-off-by: Anurag Aggarwal <a.anurag@samsung.com> Reviewed-by: Dave Martin <Dave.Martin@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2014-02-24 10:17:36 +00:00
ret = unwind_exec_pop_r4_to_rN(ctrl, insn);
if (ret)
goto error;
[ARM] 5383/2: unwind: Add core support for ARM stack unwinding This patch adds the main functionality for parsing the stack unwinding information generated by the ARM EABI toolchains. The unwinding information consists of an index with a pair of words per function and a table with unwinding instructions. For more information, see "Exception Handling ABI for the ARM Architecture" at: http://infocenter.arm.com/help/topic/com.arm.doc.subset.swdev.abi/index.html Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-02-16 10:41:36 +00:00
} else if (insn == 0xb0) {
[ARM] 5558/1: Add extra checks to ARM unwinder to avoid tracing corrupt stacks There are situations where the unwinder goes beyond stack boundaries and unwinds random data. This patch moves the stack boundaries check after the unwind_exec_insn() call and adds an extra check for possible infinite loops (like "mov pc, lr" with pc == lr). The patch also fixes a bug in the unwind instructions interpreter. The 0xb0 instruction can only set PC to LR if this wasn't already set by a previous instruction (this is used on exceptions taken while in kernel mode where svc_entry is annotated with ".save {r0 - pc}"). Tested-by: Tony Lindgren <tony@atomide.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-06-19 15:42:11 +00:00
if (ctrl->vrs[PC] == 0)
ctrl->vrs[PC] = ctrl->vrs[LR];
[ARM] 5383/2: unwind: Add core support for ARM stack unwinding This patch adds the main functionality for parsing the stack unwinding information generated by the ARM EABI toolchains. The unwinding information consists of an index with a pair of words per function and a table with unwinding instructions. For more information, see "Exception Handling ABI for the ARM Architecture" at: http://infocenter.arm.com/help/topic/com.arm.doc.subset.swdev.abi/index.html Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-02-16 10:41:36 +00:00
/* no further processing */
ctrl->entries = 0;
} else if (insn == 0xb1) {
unsigned long mask = unwind_get_byte(ctrl);
if (mask == 0 || mask & 0xf0) {
pr_warning("unwind: Spare encoding %04lx\n",
(insn << 8) | mask);
return -URC_FAILURE;
}
ARM: 7987/1: ARM : unwinder : Prevent data abort due to stack overflow While unwinding backtrace, stack overflow is possible. This stack overflow can sometimes lead to data abort in system if the area after stack is not mapped to physical memory. To prevent this problem from happening, execute the instructions that can cause a data abort in separate helper functions, where a check for feasibility is made before reading each word from the stack. Signed-off-by: Anurag Aggarwal <a.anurag@samsung.com> Reviewed-by: Dave Martin <Dave.Martin@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2014-02-24 10:17:36 +00:00
ret = unwind_exec_pop_subset_r0_to_r3(ctrl, mask);
if (ret)
goto error;
[ARM] 5383/2: unwind: Add core support for ARM stack unwinding This patch adds the main functionality for parsing the stack unwinding information generated by the ARM EABI toolchains. The unwinding information consists of an index with a pair of words per function and a table with unwinding instructions. For more information, see "Exception Handling ABI for the ARM Architecture" at: http://infocenter.arm.com/help/topic/com.arm.doc.subset.swdev.abi/index.html Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-02-16 10:41:36 +00:00
} else if (insn == 0xb2) {
unsigned long uleb128 = unwind_get_byte(ctrl);
ctrl->vrs[SP] += 0x204 + (uleb128 << 2);
} else {
pr_warning("unwind: Unhandled instruction %02lx\n", insn);
return -URC_FAILURE;
}
pr_debug("%s: fp = %08lx sp = %08lx lr = %08lx pc = %08lx\n", __func__,
ctrl->vrs[FP], ctrl->vrs[SP], ctrl->vrs[LR], ctrl->vrs[PC]);
ARM: 7987/1: ARM : unwinder : Prevent data abort due to stack overflow While unwinding backtrace, stack overflow is possible. This stack overflow can sometimes lead to data abort in system if the area after stack is not mapped to physical memory. To prevent this problem from happening, execute the instructions that can cause a data abort in separate helper functions, where a check for feasibility is made before reading each word from the stack. Signed-off-by: Anurag Aggarwal <a.anurag@samsung.com> Reviewed-by: Dave Martin <Dave.Martin@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2014-02-24 10:17:36 +00:00
error:
return ret;
[ARM] 5383/2: unwind: Add core support for ARM stack unwinding This patch adds the main functionality for parsing the stack unwinding information generated by the ARM EABI toolchains. The unwinding information consists of an index with a pair of words per function and a table with unwinding instructions. For more information, see "Exception Handling ABI for the ARM Architecture" at: http://infocenter.arm.com/help/topic/com.arm.doc.subset.swdev.abi/index.html Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-02-16 10:41:36 +00:00
}
/*
* Unwind a single frame starting with *sp for the symbol at *pc. It
* updates the *pc and *sp with the new values.
*/
int unwind_frame(struct stackframe *frame)
{
ARM: 7987/1: ARM : unwinder : Prevent data abort due to stack overflow While unwinding backtrace, stack overflow is possible. This stack overflow can sometimes lead to data abort in system if the area after stack is not mapped to physical memory. To prevent this problem from happening, execute the instructions that can cause a data abort in separate helper functions, where a check for feasibility is made before reading each word from the stack. Signed-off-by: Anurag Aggarwal <a.anurag@samsung.com> Reviewed-by: Dave Martin <Dave.Martin@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2014-02-24 10:17:36 +00:00
unsigned long low;
ARM: 7187/1: fix unwinding for XIP kernels The linker places the unwind tables in readonly sections. So when using an XIP kernel these are located in ROM and cannot be modified. For that reason the current approach to convert the relative offsets in the unwind index to absolute addresses early in the boot process doesn't work with XIP. The offsets in the unwind index section are signed 31 bit numbers and the structs are sorted by this offset. So it first has offsets between 0x40000000 and 0x7fffffff (i.e. the negative offsets) and then offsets between 0x00000000 and 0x3fffffff. When seperating these two blocks the numbers are sorted even when interpreting the offsets as unsigned longs. So determine the first non-negative entry once and track that using the new origin pointer. The actual bisection can then use a plain unsigned long comparison. The only thing that makes the new bisection more complicated is that the offsets are relative to their position in the index section, so the key to search needs to be adapted accordingly in each step. Moreover several consts are added to catch future writes and rename the member "addr" of struct unwind_idx to "addr_offset" to better match the new semantic. (This has the additional benefit of breaking eventual users at compile time to make them aware of the change.) In my tests the new algorithm was a tad faster than the original and has the additional upside of not needing the initial conversion and so saves some boot time and it's possible to unwind even earlier. Acked-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Nicolas Pitre <nico@fluxnic.net> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-12-05 08:39:59 +00:00
const struct unwind_idx *idx;
[ARM] 5383/2: unwind: Add core support for ARM stack unwinding This patch adds the main functionality for parsing the stack unwinding information generated by the ARM EABI toolchains. The unwinding information consists of an index with a pair of words per function and a table with unwinding instructions. For more information, see "Exception Handling ABI for the ARM Architecture" at: http://infocenter.arm.com/help/topic/com.arm.doc.subset.swdev.abi/index.html Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-02-16 10:41:36 +00:00
struct unwind_ctrl_block ctrl;
ARM: 7987/1: ARM : unwinder : Prevent data abort due to stack overflow While unwinding backtrace, stack overflow is possible. This stack overflow can sometimes lead to data abort in system if the area after stack is not mapped to physical memory. To prevent this problem from happening, execute the instructions that can cause a data abort in separate helper functions, where a check for feasibility is made before reading each word from the stack. Signed-off-by: Anurag Aggarwal <a.anurag@samsung.com> Reviewed-by: Dave Martin <Dave.Martin@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2014-02-24 10:17:36 +00:00
/* store the highest address on the stack to avoid crossing it*/
[ARM] 5383/2: unwind: Add core support for ARM stack unwinding This patch adds the main functionality for parsing the stack unwinding information generated by the ARM EABI toolchains. The unwinding information consists of an index with a pair of words per function and a table with unwinding instructions. For more information, see "Exception Handling ABI for the ARM Architecture" at: http://infocenter.arm.com/help/topic/com.arm.doc.subset.swdev.abi/index.html Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-02-16 10:41:36 +00:00
low = frame->sp;
ARM: 7987/1: ARM : unwinder : Prevent data abort due to stack overflow While unwinding backtrace, stack overflow is possible. This stack overflow can sometimes lead to data abort in system if the area after stack is not mapped to physical memory. To prevent this problem from happening, execute the instructions that can cause a data abort in separate helper functions, where a check for feasibility is made before reading each word from the stack. Signed-off-by: Anurag Aggarwal <a.anurag@samsung.com> Reviewed-by: Dave Martin <Dave.Martin@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2014-02-24 10:17:36 +00:00
ctrl.sp_high = ALIGN(low, THREAD_SIZE);
[ARM] 5383/2: unwind: Add core support for ARM stack unwinding This patch adds the main functionality for parsing the stack unwinding information generated by the ARM EABI toolchains. The unwinding information consists of an index with a pair of words per function and a table with unwinding instructions. For more information, see "Exception Handling ABI for the ARM Architecture" at: http://infocenter.arm.com/help/topic/com.arm.doc.subset.swdev.abi/index.html Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-02-16 10:41:36 +00:00
pr_debug("%s(pc = %08lx lr = %08lx sp = %08lx)\n", __func__,
frame->pc, frame->lr, frame->sp);
if (!kernel_text_address(frame->pc))
return -URC_FAILURE;
idx = unwind_find_idx(frame->pc);
if (!idx) {
pr_warning("unwind: Index not found %08lx\n", frame->pc);
return -URC_FAILURE;
}
ctrl.vrs[FP] = frame->fp;
ctrl.vrs[SP] = frame->sp;
ctrl.vrs[LR] = frame->lr;
ctrl.vrs[PC] = 0;
if (idx->insn == 1)
/* can't unwind */
return -URC_FAILURE;
else if ((idx->insn & 0x80000000) == 0)
/* prel31 to the unwind table */
ctrl.insn = (unsigned long *)prel31_to_addr(&idx->insn);
else if ((idx->insn & 0xff000000) == 0x80000000)
/* only personality routine 0 supported in the index */
ctrl.insn = &idx->insn;
else {
pr_warning("unwind: Unsupported personality routine %08lx in the index at %p\n",
idx->insn, idx);
return -URC_FAILURE;
}
/* check the personality routine */
if ((*ctrl.insn & 0xff000000) == 0x80000000) {
ctrl.byte = 2;
ctrl.entries = 1;
} else if ((*ctrl.insn & 0xff000000) == 0x81000000) {
ctrl.byte = 1;
ctrl.entries = 1 + ((*ctrl.insn & 0x00ff0000) >> 16);
} else {
pr_warning("unwind: Unsupported personality routine %08lx at %p\n",
*ctrl.insn, ctrl.insn);
return -URC_FAILURE;
}
ARM: 7987/1: ARM : unwinder : Prevent data abort due to stack overflow While unwinding backtrace, stack overflow is possible. This stack overflow can sometimes lead to data abort in system if the area after stack is not mapped to physical memory. To prevent this problem from happening, execute the instructions that can cause a data abort in separate helper functions, where a check for feasibility is made before reading each word from the stack. Signed-off-by: Anurag Aggarwal <a.anurag@samsung.com> Reviewed-by: Dave Martin <Dave.Martin@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2014-02-24 10:17:36 +00:00
ctrl.check_each_pop = 0;
[ARM] 5383/2: unwind: Add core support for ARM stack unwinding This patch adds the main functionality for parsing the stack unwinding information generated by the ARM EABI toolchains. The unwinding information consists of an index with a pair of words per function and a table with unwinding instructions. For more information, see "Exception Handling ABI for the ARM Architecture" at: http://infocenter.arm.com/help/topic/com.arm.doc.subset.swdev.abi/index.html Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-02-16 10:41:36 +00:00
while (ctrl.entries > 0) {
ARM: 7987/1: ARM : unwinder : Prevent data abort due to stack overflow While unwinding backtrace, stack overflow is possible. This stack overflow can sometimes lead to data abort in system if the area after stack is not mapped to physical memory. To prevent this problem from happening, execute the instructions that can cause a data abort in separate helper functions, where a check for feasibility is made before reading each word from the stack. Signed-off-by: Anurag Aggarwal <a.anurag@samsung.com> Reviewed-by: Dave Martin <Dave.Martin@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2014-02-24 10:17:36 +00:00
int urc;
if ((ctrl.sp_high - ctrl.vrs[SP]) < sizeof(ctrl.vrs))
ctrl.check_each_pop = 1;
urc = unwind_exec_insn(&ctrl);
[ARM] 5383/2: unwind: Add core support for ARM stack unwinding This patch adds the main functionality for parsing the stack unwinding information generated by the ARM EABI toolchains. The unwinding information consists of an index with a pair of words per function and a table with unwinding instructions. For more information, see "Exception Handling ABI for the ARM Architecture" at: http://infocenter.arm.com/help/topic/com.arm.doc.subset.swdev.abi/index.html Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-02-16 10:41:36 +00:00
if (urc < 0)
return urc;
ARM: 7987/1: ARM : unwinder : Prevent data abort due to stack overflow While unwinding backtrace, stack overflow is possible. This stack overflow can sometimes lead to data abort in system if the area after stack is not mapped to physical memory. To prevent this problem from happening, execute the instructions that can cause a data abort in separate helper functions, where a check for feasibility is made before reading each word from the stack. Signed-off-by: Anurag Aggarwal <a.anurag@samsung.com> Reviewed-by: Dave Martin <Dave.Martin@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2014-02-24 10:17:36 +00:00
if (ctrl.vrs[SP] < low || ctrl.vrs[SP] >= ctrl.sp_high)
[ARM] 5558/1: Add extra checks to ARM unwinder to avoid tracing corrupt stacks There are situations where the unwinder goes beyond stack boundaries and unwinds random data. This patch moves the stack boundaries check after the unwind_exec_insn() call and adds an extra check for possible infinite loops (like "mov pc, lr" with pc == lr). The patch also fixes a bug in the unwind instructions interpreter. The 0xb0 instruction can only set PC to LR if this wasn't already set by a previous instruction (this is used on exceptions taken while in kernel mode where svc_entry is annotated with ".save {r0 - pc}"). Tested-by: Tony Lindgren <tony@atomide.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-06-19 15:42:11 +00:00
return -URC_FAILURE;
[ARM] 5383/2: unwind: Add core support for ARM stack unwinding This patch adds the main functionality for parsing the stack unwinding information generated by the ARM EABI toolchains. The unwinding information consists of an index with a pair of words per function and a table with unwinding instructions. For more information, see "Exception Handling ABI for the ARM Architecture" at: http://infocenter.arm.com/help/topic/com.arm.doc.subset.swdev.abi/index.html Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-02-16 10:41:36 +00:00
}
if (ctrl.vrs[PC] == 0)
ctrl.vrs[PC] = ctrl.vrs[LR];
[ARM] 5558/1: Add extra checks to ARM unwinder to avoid tracing corrupt stacks There are situations where the unwinder goes beyond stack boundaries and unwinds random data. This patch moves the stack boundaries check after the unwind_exec_insn() call and adds an extra check for possible infinite loops (like "mov pc, lr" with pc == lr). The patch also fixes a bug in the unwind instructions interpreter. The 0xb0 instruction can only set PC to LR if this wasn't already set by a previous instruction (this is used on exceptions taken while in kernel mode where svc_entry is annotated with ".save {r0 - pc}"). Tested-by: Tony Lindgren <tony@atomide.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-06-19 15:42:11 +00:00
/* check for infinite loop */
if (frame->pc == ctrl.vrs[PC])
return -URC_FAILURE;
[ARM] 5383/2: unwind: Add core support for ARM stack unwinding This patch adds the main functionality for parsing the stack unwinding information generated by the ARM EABI toolchains. The unwinding information consists of an index with a pair of words per function and a table with unwinding instructions. For more information, see "Exception Handling ABI for the ARM Architecture" at: http://infocenter.arm.com/help/topic/com.arm.doc.subset.swdev.abi/index.html Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-02-16 10:41:36 +00:00
frame->fp = ctrl.vrs[FP];
frame->sp = ctrl.vrs[SP];
frame->lr = ctrl.vrs[LR];
frame->pc = ctrl.vrs[PC];
return URC_OK;
}
void unwind_backtrace(struct pt_regs *regs, struct task_struct *tsk)
{
struct stackframe frame;
register unsigned long current_sp asm ("sp");
pr_debug("%s(regs = %p tsk = %p)\n", __func__, regs, tsk);
if (!tsk)
tsk = current;
if (regs) {
ARM: 8073/1: unwind: Use arm_get_current_stackframe Make the unwind code use the correct API so that the frame pointer is extracted from the correct register. Signed-off-by: Nikolay Borisov <Nikolay.Borisov@arm.com> Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2014-06-03 18:49:14 +00:00
arm_get_current_stackframe(regs, &frame);
ARM: 5977/1: arm: Enable backtrace printing on oops when PC is corrupted If PC points outside kernel text, start printing the backtrace at LR instead. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-03-04 14:33:16 +00:00
/* PC might be corrupted, use LR in that case. */
ARM: 8073/1: unwind: Use arm_get_current_stackframe Make the unwind code use the correct API so that the frame pointer is extracted from the correct register. Signed-off-by: Nikolay Borisov <Nikolay.Borisov@arm.com> Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2014-06-03 18:49:14 +00:00
if (!kernel_text_address(regs->ARM_pc))
frame.pc = regs->ARM_lr;
[ARM] 5383/2: unwind: Add core support for ARM stack unwinding This patch adds the main functionality for parsing the stack unwinding information generated by the ARM EABI toolchains. The unwinding information consists of an index with a pair of words per function and a table with unwinding instructions. For more information, see "Exception Handling ABI for the ARM Architecture" at: http://infocenter.arm.com/help/topic/com.arm.doc.subset.swdev.abi/index.html Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-02-16 10:41:36 +00:00
} else if (tsk == current) {
frame.fp = (unsigned long)__builtin_frame_address(0);
frame.sp = current_sp;
frame.lr = (unsigned long)__builtin_return_address(0);
frame.pc = (unsigned long)unwind_backtrace;
} else {
/* task blocked in __switch_to */
frame.fp = thread_saved_fp(tsk);
frame.sp = thread_saved_sp(tsk);
/*
* The function calling __switch_to cannot be a leaf function
* so LR is recovered from the stack.
*/
frame.lr = 0;
frame.pc = thread_saved_pc(tsk);
}
while (1) {
int urc;
unsigned long where = frame.pc;
urc = unwind_frame(&frame);
if (urc < 0)
break;
dump_backtrace_entry(where, frame.pc, frame.sp - 4);
}
}
struct unwind_table *unwind_table_add(unsigned long start, unsigned long size,
unsigned long text_addr,
unsigned long text_size)
{
unsigned long flags;
struct unwind_table *tab = kmalloc(sizeof(*tab), GFP_KERNEL);
pr_debug("%s(%08lx, %08lx, %08lx, %08lx)\n", __func__, start, size,
text_addr, text_size);
if (!tab)
return tab;
ARM: 7187/1: fix unwinding for XIP kernels The linker places the unwind tables in readonly sections. So when using an XIP kernel these are located in ROM and cannot be modified. For that reason the current approach to convert the relative offsets in the unwind index to absolute addresses early in the boot process doesn't work with XIP. The offsets in the unwind index section are signed 31 bit numbers and the structs are sorted by this offset. So it first has offsets between 0x40000000 and 0x7fffffff (i.e. the negative offsets) and then offsets between 0x00000000 and 0x3fffffff. When seperating these two blocks the numbers are sorted even when interpreting the offsets as unsigned longs. So determine the first non-negative entry once and track that using the new origin pointer. The actual bisection can then use a plain unsigned long comparison. The only thing that makes the new bisection more complicated is that the offsets are relative to their position in the index section, so the key to search needs to be adapted accordingly in each step. Moreover several consts are added to catch future writes and rename the member "addr" of struct unwind_idx to "addr_offset" to better match the new semantic. (This has the additional benefit of breaking eventual users at compile time to make them aware of the change.) In my tests the new algorithm was a tad faster than the original and has the additional upside of not needing the initial conversion and so saves some boot time and it's possible to unwind even earlier. Acked-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Nicolas Pitre <nico@fluxnic.net> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-12-05 08:39:59 +00:00
tab->start = (const struct unwind_idx *)start;
tab->stop = (const struct unwind_idx *)(start + size);
tab->origin = unwind_find_origin(tab->start, tab->stop);
[ARM] 5383/2: unwind: Add core support for ARM stack unwinding This patch adds the main functionality for parsing the stack unwinding information generated by the ARM EABI toolchains. The unwinding information consists of an index with a pair of words per function and a table with unwinding instructions. For more information, see "Exception Handling ABI for the ARM Architecture" at: http://infocenter.arm.com/help/topic/com.arm.doc.subset.swdev.abi/index.html Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-02-16 10:41:36 +00:00
tab->begin_addr = text_addr;
tab->end_addr = text_addr + text_size;
spin_lock_irqsave(&unwind_lock, flags);
list_add_tail(&tab->list, &unwind_tables);
spin_unlock_irqrestore(&unwind_lock, flags);
return tab;
}
void unwind_table_del(struct unwind_table *tab)
{
unsigned long flags;
if (!tab)
return;
spin_lock_irqsave(&unwind_lock, flags);
list_del(&tab->list);
spin_unlock_irqrestore(&unwind_lock, flags);
kfree(tab);
}
Reference in New Issue Copy Permalink