The broadcast tick recipient can call tick_receive_broadcast rather
than re-running the full timer interrupt.
It does not have to check for the next event time, because the sender
already determined the timer has expired. It does not have to test
irq_work_pending, because that's a direct decrementer interrupt and
does not go through the clock events subsystem. And it does not have
to read PURR because that was removed with the previous patch.
This results in no code size change, but both the decrementer and
broadcast path lengths are reduced.
Cc: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Cc: Preeti U Murthy <preeti@linux.vnet.ibm.com>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
For SPLPAR, lparcfg provides a sum of PURR registers for all CPUs.
Currently this is done by reading PURR in context switch and timer
interrupt, and storing that into a per-CPU variable. These are summed
to provide the value.
This does not work with all timer schemes (e.g., NO_HZ_FULL), and it
is sub-optimal for performance because it reads the PURR register on
every context switch, although that's been difficult to distinguish
from noise in the contxt_switch microbenchmark.
This patch implements the sum by calling a function on each CPU, to
read and add PURR values of each CPU.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
irq_work_raise should not cause a decrementer exception unless it is
called from NMI context. Doing so often just results in an immediate
masked decrementer interrupt:
<...>-550 90d... 4us : update_curr_rt <-dequeue_task_rt
<...>-550 90d... 5us : dbs_update_util_handler <-update_curr_rt
<...>-550 90d... 6us : arch_irq_work_raise <-irq_work_queue
<...>-550 90d... 7us : soft_nmi_interrupt <-soft_nmi_common
<...>-550 90d... 7us : printk_nmi_enter <-soft_nmi_interrupt
<...>-550 90d.Z. 8us : rcu_nmi_enter <-soft_nmi_interrupt
<...>-550 90d.Z. 9us : rcu_nmi_exit <-soft_nmi_interrupt
<...>-550 90d... 9us : printk_nmi_exit <-soft_nmi_interrupt
<...>-550 90d... 10us : cpuacct_charge <-update_curr_rt
The soft_nmi_interrupt here is the call into the watchdog, due to the
decrementer interrupt firing with irqs soft-disabled. This is
harmless, but sub-optimal.
When it's not called from NMI context or with interrupts enabled, mark
the decrementer pending in the irq_happened mask directly, rather than
having the masked decrementer interupt handler do it. This will be
replayed at the next local_irq_enable. See the comment for details.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
GCC 8.1 emits warnings such as the following. As arch/powerpc code is
built with -Werror, this breaks the build with GCC 8.1.
In file included from arch/powerpc/kernel/pci_64.c:23:
./include/linux/syscalls.h:233:18: error: 'sys_pciconfig_iobase' alias
between functions of incompatible types 'long int(long int, long
unsigned int, long unsigned int)' and 'long int(long int, long int,
long int)' [-Werror=attribute-alias]
asmlinkage long sys##name(__MAP(x,__SC_DECL,__VA_ARGS__)) \
^~~
./include/linux/syscalls.h:222:2: note: in expansion of macro '__SYSCALL_DEFINEx'
__SYSCALL_DEFINEx(x, sname, __VA_ARGS__)
This patch inhibits those warnings.
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
[mpe: Trim change log]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
GCC 8.1 warns about possible string truncation:
arch/powerpc/kernel/nvram_64.c:1042:2: error: 'strncpy' specified
bound 12 equals destination size [-Werror=stringop-truncation]
strncpy(new_part->header.name, name, 12);
arch/powerpc/platforms/ps3/repository.c:106:2: error: 'strncpy'
output truncated before terminating nul copying 8 bytes from a
string of the same length [-Werror=stringop-truncation]
strncpy((char *)&n, text, 8);
Fix it by using memcpy(). To make that safe we need to ensure the
destination is pre-zeroed. Use kzalloc() in the nvram code and
initialise the u64 to zero in the ps3 code.
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
[mpe: Use kzalloc() in the nvram code, flesh out change log]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
We ended up with an ugly conflict between fixes and next in ftrace.h
involving multiple nested ifdefs, and the automatic resolution is
wrong. So merge fixes into next so we can fix it up.
In commit eae5f709a4 ("powerpc: Add __printf verification to
prom_printf") __printf attribute was added to prom_printf(), which
means GCC started warning about type/format mismatches. As part of
that commit we changed some "%lx" formats to "%llx" where the type is
actually unsigned long long.
Unfortunately prom_printf() doesn't know how to print "%llx", it just
prints a literal "lx", eg:
reserved memory map:
lx - lx
lx - lx
prom_printf() also doesn't know how to print "%u" (only "%lu"), it
just prints a literal "u", eg:
Max number of cores passed to firmware: u (NR_CPUS = 2048)
Instead of:
Max number of cores passed to firmware: 2048 (NR_CPUS = 2048)
This commit adds support for the missing formatters.
Fixes: eae5f709a4 ("powerpc: Add __printf verification to prom_printf")
Reported-by: Michael Ellerman <mpe@ellerman.id.au>
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Mathieu Malaterre <malat@debian.org>
Tested-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Switch VDSO32 build over to use CROSS32_COMPILE directly, and have
it pass in -m32 after the standard c_flags. This allows endianness
overrides to be removed and the endian and bitness flags moved into
standard flags variables.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
The toc field in the mod_arch_specific struct isn't actually used
anywhere, so remove it.
Also the ftrace-specific fields are now common between 32-bit and
64-bit, so simplify the struct definition a bit by moving them out of
the __powerpc64__ #ifdef.
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Reviewed-by: Kamalesh Babulal <kamalesh@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
The header file <asm/switch_to.h> was missing from the includes. Fix the
following warning, treated as error with W=1:
arch/powerpc/kernel/vecemu.c:260:5: error: no previous prototype for ‘emulate_altivec’ [-Werror=missing-prototypes]
Signed-off-by: Mathieu Malaterre <malat@debian.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
The header file <linux/syscalls.h> was missing from the includes. Fix the
following warning, treated as error with W=1:
arch/powerpc/kernel/pci_32.c:286:6: error: no previous prototype for ‘sys_pciconfig_iobase’ [-Werror=missing-prototypes]
Signed-off-by: Mathieu Malaterre <malat@debian.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
These functions can all be static, make it so. Fix warnings treated as
errors with W=1:
arch/powerpc/kernel/tau_6xx.c:53:6: error: no previous prototype for ‘set_thresholds’ [-Werror=missing-prototypes]
arch/powerpc/kernel/tau_6xx.c:73:6: error: no previous prototype for ‘TAUupdate’ [-Werror=missing-prototypes]
arch/powerpc/kernel/tau_6xx.c:208:13: error: no previous prototype for ‘TAU_init_smp’ [-Werror=missing-prototypes]
arch/powerpc/kernel/tau_6xx.c:220:12: error: no previous prototype for ‘TAU_init’ [-Werror=missing-prototypes]
arch/powerpc/kernel/tau_6xx.c:126:6: error: no previous prototype for ‘TAUException’ [-Werror=missing-prototypes]
Signed-off-by: Mathieu Malaterre <malat@debian.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This function can be static, make it so, this fix a warning treated as
error with W=1:
arch/powerpc/kernel/btext.c:173:5: error: no previous prototype for ‘btext_initialize’ [-Werror=missing-prototypes]
Signed-off-by: Mathieu Malaterre <malat@debian.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Some function prototypes and body for Thermal Assist Units were not in
sync. Update the function definition to match the existing function
declaration found in `setup-common.c`, changing an `int` return type to a
`u32` return type. Move the prototypes to a header file. Fix the following
warnings, treated as error with W=1:
arch/powerpc/kernel/tau_6xx.c:257:5: error: no previous prototype for ‘cpu_temp_both’ [-Werror=missing-prototypes]
arch/powerpc/kernel/tau_6xx.c:262:5: error: no previous prototype for ‘cpu_temp’ [-Werror=missing-prototypes]
arch/powerpc/kernel/tau_6xx.c:267:5: error: no previous prototype for ‘tau_interrupts’ [-Werror=missing-prototypes]
Compile tested with CONFIG_TAU_INT.
Suggested-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Mathieu Malaterre <malat@debian.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
In commit 7a22d6321c ("powerpc/mm/radix: Update command line parsing for
disable_radix") an `if` statement was added for a possible empty body
(prom_debug).
Fix the following warning, treated as error with W=1:
arch/powerpc/kernel/prom_init.c:656:46: error: suggest braces around empty body in an ‘if’ statement [-Werror=empty-body]
Suggested-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Mathieu Malaterre <malat@debian.org>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Trivial fix to remove the following sparse warnings:
arch/powerpc/kernel/module_32.c:112:74: warning: Using plain integer as NULL pointer
arch/powerpc/kernel/module_32.c:117:74: warning: Using plain integer as NULL pointer
drivers/macintosh/via-pmu.c:1155:28: warning: Using plain integer as NULL pointer
drivers/macintosh/via-pmu.c:1230:20: warning: Using plain integer as NULL pointer
drivers/macintosh/via-pmu.c:1385:36: warning: Using plain integer as NULL pointer
drivers/macintosh/via-pmu.c:1752:23: warning: Using plain integer as NULL pointer
drivers/macintosh/via-pmu.c:2084:19: warning: Using plain integer as NULL pointer
drivers/macintosh/via-pmu.c:2110:32: warning: Using plain integer as NULL pointer
drivers/macintosh/via-pmu.c:2167:19: warning: Using plain integer as NULL pointer
drivers/macintosh/via-pmu.c:2183:19: warning: Using plain integer as NULL pointer
drivers/macintosh/via-pmu.c:277:20: warning: Using plain integer as NULL pointer
arch/powerpc/platforms/powermac/setup.c:155:67: warning: Using plain integer as NULL pointer
arch/powerpc/platforms/powermac/setup.c:247:27: warning: Using plain integer as NULL pointer
arch/powerpc/platforms/powermac/setup.c:249:27: warning: Using plain integer as NULL pointer
arch/powerpc/platforms/powermac/setup.c:252:37: warning: Using plain integer as NULL pointer
arch/powerpc/mm/tlb_hash32.c:127:21: warning: Using plain integer as NULL pointer
arch/powerpc/mm/tlb_hash32.c:148:21: warning: Using plain integer as NULL pointer
arch/powerpc/mm/tlb_hash32.c:44:21: warning: Using plain integer as NULL pointer
arch/powerpc/mm/tlb_hash32.c:57:21: warning: Using plain integer as NULL pointer
arch/powerpc/mm/tlb_hash32.c:87:21: warning: Using plain integer as NULL pointer
arch/powerpc/kernel/btext.c:160:31: warning: Using plain integer as NULL pointer
arch/powerpc/kernel/btext.c:167:22: warning: Using plain integer as NULL pointer
arch/powerpc/kernel/btext.c:274:21: warning: Using plain integer as NULL pointer
arch/powerpc/kernel/btext.c:285:31: warning: Using plain integer as NULL pointer
arch/powerpc/include/asm/hugetlb.h:204:16: warning: Using plain integer as NULL pointer
arch/powerpc/mm/ppc_mmu_32.c:170:21: warning: Using plain integer as NULL pointer
arch/powerpc/platforms/powermac/pci.c:1227:23: warning: Using plain integer as NULL pointer
arch/powerpc/platforms/powermac/pci.c:65:24: warning: Using plain integer as NULL pointer
Also use `--fix` command line option from `script/checkpatch --strict` to
remove the following:
CHECK: Comparison to NULL could be written "!dispDeviceBase"
#72: FILE: arch/powerpc/kernel/btext.c:160:
+ if (dispDeviceBase == NULL)
CHECK: Comparison to NULL could be written "!vbase"
#80: FILE: arch/powerpc/kernel/btext.c:167:
+ if (vbase == NULL)
CHECK: Comparison to NULL could be written "!base"
#89: FILE: arch/powerpc/kernel/btext.c:274:
+ if (base == NULL)
CHECK: Comparison to NULL could be written "!dispDeviceBase"
#98: FILE: arch/powerpc/kernel/btext.c:285:
+ if (dispDeviceBase == NULL)
CHECK: Comparison to NULL could be written "strstr"
#117: FILE: arch/powerpc/kernel/module_32.c:117:
+ if (strstr(secstrings + sechdrs[i].sh_name, ".debug") != NULL)
CHECK: Comparison to NULL could be written "!Hash"
#130: FILE: arch/powerpc/mm/ppc_mmu_32.c:170:
+ if (Hash == NULL)
CHECK: Comparison to NULL could be written "Hash"
#143: FILE: arch/powerpc/mm/tlb_hash32.c:44:
+ if (Hash != NULL) {
CHECK: Comparison to NULL could be written "!Hash"
#152: FILE: arch/powerpc/mm/tlb_hash32.c:57:
+ if (Hash == NULL) {
CHECK: Comparison to NULL could be written "!Hash"
#161: FILE: arch/powerpc/mm/tlb_hash32.c:87:
+ if (Hash == NULL) {
CHECK: Comparison to NULL could be written "!Hash"
#170: FILE: arch/powerpc/mm/tlb_hash32.c:127:
+ if (Hash == NULL) {
CHECK: Comparison to NULL could be written "!Hash"
#179: FILE: arch/powerpc/mm/tlb_hash32.c:148:
+ if (Hash == NULL) {
ERROR: space required after that ';' (ctx:VxV)
#192: FILE: arch/powerpc/platforms/powermac/pci.c:65:
+ for (; node != NULL;node = node->sibling) {
CHECK: Comparison to NULL could be written "node"
#192: FILE: arch/powerpc/platforms/powermac/pci.c:65:
+ for (; node != NULL;node = node->sibling) {
CHECK: Comparison to NULL could be written "!region"
#201: FILE: arch/powerpc/platforms/powermac/pci.c:1227:
+ if (region == NULL)
CHECK: Comparison to NULL could be written "of_get_property"
#214: FILE: arch/powerpc/platforms/powermac/setup.c:155:
+ if (of_get_property(np, "cache-unified", NULL) != NULL && dc) {
CHECK: Comparison to NULL could be written "!np"
#223: FILE: arch/powerpc/platforms/powermac/setup.c:247:
+ if (np == NULL)
CHECK: Comparison to NULL could be written "np"
#226: FILE: arch/powerpc/platforms/powermac/setup.c:249:
+ if (np != NULL) {
CHECK: Comparison to NULL could be written "l2cr"
#230: FILE: arch/powerpc/platforms/powermac/setup.c:252:
+ if (l2cr != NULL) {
CHECK: Comparison to NULL could be written "via"
#243: FILE: drivers/macintosh/via-pmu.c:277:
+ if (via != NULL)
CHECK: Comparison to NULL could be written "current_req"
#252: FILE: drivers/macintosh/via-pmu.c:1155:
+ if (current_req != NULL) {
CHECK: Comparison to NULL could be written "!req"
#261: FILE: drivers/macintosh/via-pmu.c:1230:
+ if (req == NULL || pmu_state != idle
CHECK: Comparison to NULL could be written "!req"
#270: FILE: drivers/macintosh/via-pmu.c:1385:
+ if (req == NULL) {
CHECK: Comparison to NULL could be written "!pp"
#288: FILE: drivers/macintosh/via-pmu.c:2084:
+ if (pp == NULL)
CHECK: Comparison to NULL could be written "!pp"
#297: FILE: drivers/macintosh/via-pmu.c:2110:
+ if (count < 1 || pp == NULL)
CHECK: Comparison to NULL could be written "!pp"
#306: FILE: drivers/macintosh/via-pmu.c:2167:
+ if (pp == NULL)
CHECK: Comparison to NULL could be written "pp"
#315: FILE: drivers/macintosh/via-pmu.c:2183:
+ if (pp != NULL) {
Link: https://github.com/linuxppc/linux/issues/37
Signed-off-by: Mathieu Malaterre <malat@debian.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
__printf is useful to verify format and arguments. Fix arg mismatch
reported by gcc, remove the following warnings (with W=1):
arch/powerpc/kernel/prom_init.c:1467:31: error: format ‘%x’ expects argument of type ‘unsigned int’, but argument 2 has type ‘long unsigned int’
arch/powerpc/kernel/prom_init.c:1471:31: error: format ‘%x’ expects argument of type ‘unsigned int’, but argument 2 has type ‘long unsigned int’
arch/powerpc/kernel/prom_init.c:1504:33: error: format ‘%x’ expects argument of type ‘unsigned int’, but argument 2 has type ‘long unsigned int’
arch/powerpc/kernel/prom_init.c:1505:33: error: format ‘%x’ expects argument of type ‘unsigned int’, but argument 2 has type ‘long unsigned int’
arch/powerpc/kernel/prom_init.c:1506:33: error: format ‘%x’ expects argument of type ‘unsigned int’, but argument 2 has type ‘long unsigned int’
arch/powerpc/kernel/prom_init.c:1507:33: error: format ‘%x’ expects argument of type ‘unsigned int’, but argument 2 has type ‘long unsigned int’
arch/powerpc/kernel/prom_init.c:1508:33: error: format ‘%x’ expects argument of type ‘unsigned int’, but argument 2 has type ‘long unsigned int’
arch/powerpc/kernel/prom_init.c:1509:33: error: format ‘%x’ expects argument of type ‘unsigned int’, but argument 2 has type ‘long unsigned int’
arch/powerpc/kernel/prom_init.c:1975:39: error: format ‘%lu’ expects argument of type ‘long unsigned int’, but argument 2 has type ‘unsigned int’
arch/powerpc/kernel/prom_init.c:1986:27: error: format ‘%x’ expects argument of type ‘unsigned int’, but argument 2 has type ‘long unsigned int’
arch/powerpc/kernel/prom_init.c:2567:38: error: format ‘%x’ expects argument of type ‘unsigned int’, but argument 2 has type ‘long unsigned int’
arch/powerpc/kernel/prom_init.c:2567:46: error: format ‘%x’ expects argument of type ‘unsigned int’, but argument 3 has type ‘long unsigned int’
arch/powerpc/kernel/prom_init.c:2569:38: error: format ‘%x’ expects argument of type ‘unsigned int’, but argument 2 has type ‘long unsigned int’
arch/powerpc/kernel/prom_init.c:2569:46: error: format ‘%x’ expects argument of type ‘unsigned int’, but argument 3 has type ‘long unsigned int’
The patch also include arg mismatch fix for case with #define DEBUG_PROM
(warning not listed here).
This patch fix also the following warnings revealed by checkpatch:
WARNING: Prefer using '"%s...", __func__' to using 'alloc_up', this function's name, in a string
#101: FILE: arch/powerpc/kernel/prom_init.c:1235:
+ prom_debug("alloc_up(%lx, %lx)\n", size, align);
and
WARNING: Prefer using '"%s...", __func__' to using 'alloc_down', this function's name, in a string
#138: FILE: arch/powerpc/kernel/prom_init.c:1278:
+ prom_debug("alloc_down(%lx, %lx, %s)\n", size, align,
Signed-off-by: Mathieu Malaterre <malat@debian.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
New binutils generate the following warning
AS arch/powerpc/kernel/head_8xx.o
arch/powerpc/kernel/head_8xx.S: Assembler messages:
arch/powerpc/kernel/head_8xx.S:916: Warning: invalid register expression
This patch fixes it.
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This patch exports tm_enable()/tm_disable/tm_abort() APIs, which
will be used for PR KVM transactional memory logic.
Signed-off-by: Simon Guo <wei.guo.simon@gmail.com>
Reviewed-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
PR KVM will need to reuse msr_check_and_set().
This patch exports this API for reuse.
Signed-off-by: Simon Guo <wei.guo.simon@gmail.com>
Reviewed-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
In commit e2a800beac ("powerpc/hw_brk: Fix off by one error when
validating DAWR region end") we fixed setting the DAWR end point to
its max value via PPC_PTRACE_SETHWDEBUG. Unfortunately we broke
PTRACE_SET_DEBUGREG when setting a 512 byte aligned breakpoint.
PTRACE_SET_DEBUGREG currently sets the length of the breakpoint to
zero (memset() in hw_breakpoint_init()). This worked with
arch_validate_hwbkpt_settings() before the above patch was applied but
is now broken if the breakpoint is 512byte aligned.
This sets the length of the breakpoint to 8 bytes when using
PTRACE_SET_DEBUGREG.
Fixes: e2a800beac ("powerpc/hw_brk: Fix off by one error when validating DAWR region end")
Cc: stable@vger.kernel.org # v3.11+
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Back when we first introduced the DAWR, in commit 4ae7ebe952
("powerpc: Change hardware breakpoint to allow longer ranges"), we
screwed up the constraint making it a 1024 byte boundary rather than a
512. This makes the check overly permissive. Fortunately GDB is the
only real user and it always did they right thing, so we never
noticed.
This fixes the constraint to 512 bytes.
Fixes: 4ae7ebe952 ("powerpc: Change hardware breakpoint to allow longer ranges")
Cc: stable@vger.kernel.org # v3.9+
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Trivial fix to spelling mistake in battery_charging array.
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Clear the PCR (Processor Compatibility Register) on boot to ensure we
are not running in a compatibility mode.
We've seen this cause problems when a crash (and kdump) occurs while
running compat mode guests. The kdump kernel then runs with the PCR
set and causes problems. The symptom in the kdump kernel (also seen in
petitboot after fast-reboot) is early userspace programs taking
sigills on newer instructions (seen in libc).
Signed-off-by: Michael Neuling <mikey@neuling.org>
Cc: stable@vger.kernel.org
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
arch/powerpc/Makefile activates -mmultiple on BE PPC32 configs
in order to use multiple word instructions in functions entry/exit.
The patch does the same for the asm parts, for consistency.
On processors like the 8xx on which insn fetching is pretty slow,
this speeds up registers save/restore.
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
[mpe: PPC32 is BE only, so drop the endian checks]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Doing the test at exit of the function avoids an unnecessary
test and branch inside longjmp().
Semantics are unchanged.
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Reviewed-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Directly use fault_in_pages_readable instead of manual __get_user code. Fix
warning treated as error with W=1:
arch/powerpc/kernel/kvm.c:675:6: error: variable ‘tmp’ set but not used [-Werror=unused-but-set-variable]
Suggested-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Mathieu Malaterre <malat@debian.org>
Reviewed-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
In commit e6a6928c3e ("of/fdt: Convert FDT functions to use
libfdt") (Apr 2014), the generic flat device tree code dropped support
for flat device tree's older than version 0x10 (16).
We still have code in our CPU scanning to cope with flat device tree
versions earlier than 2, which can now never trigger, so drop it.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
If the systbl_chk.sh checks fail we print a message, but with no
indication that it's an error. That makes it hard to find in build
logs with eg. grep.
So prefix any output with "Error:".
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
it had always been pointless - compat_sys_select() sign-extends
the first argument just fine on its own.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
[mpe: Use COMPAT_SPU_NEW() to keep systbl_chk.sh happy]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Currently the select system call is wired up with the SYSX_SPU()
macro. The SYSX_SPU() is not handled by systbl_chk.c, which means the
syscall number for select is not checked.
That hides the fact that the syscall number for select is actually
__NR__newselect not __NR_select.
In a following patch we'd like to drop ppc32_select() which means
select will become a regular COMPAT_SYS_SPU() syscall. But
COMPAT_SYS_SPU() can't deal with the fact that the syscall number is
actually __NR__newselect. We also can't just redefine __NR_select
because that's still used for the old select call.
So add a new COMPAT_NEW_SPU() that does the same thing as
COMPAT_SYS_SPU() except it encodes that we're using the new number.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
[mpe: Fix sys_debug_setcontext() prototype to return long]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
The "Power Architecture 64-Bit ELF V2 ABI" says in section 2.3.2.3:
[...] There are several rules that must be adhered to in order to ensure
reliable and consistent call chain backtracing:
* Before a function calls any other function, it shall establish its
own stack frame, whose size shall be a multiple of 16 bytes.
– In instances where a function’s prologue creates a stack frame, the
back-chain word of the stack frame shall be updated atomically with
the value of the stack pointer (r1) when a back chain is implemented.
(This must be supported as default by all ELF V2 ABI-compliant
environments.)
[...]
– The function shall save the link register that contains its return
address in the LR save doubleword of its caller’s stack frame before
calling another function.
To me this sounds like the equivalent of HAVE_RELIABLE_STACKTRACE.
This patch may be unneccessarily limited to ppc64le, but OTOH the only
user of this flag so far is livepatching, which is only implemented on
PPCs with 64-LE, a.k.a. ELF ABI v2.
Feel free to add other ppc variants, but so far only ppc64le got tested.
This change also implements save_stack_trace_tsk_reliable() for ppc64le
that checks for the above conditions, where possible.
Signed-off-by: Torsten Duwe <duwe@suse.de>
Signed-off-by: Nicolai Stange <nstange@suse.de>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Provide timebase and timebase of last heartbeat in watchdog lockup
messages. Also provide a stack trace of when a CPU becomes un-stuck,
which can be useful -- it could be where irqs are re-enabled, so it
may be the end of the critical section which is responsible for the
latency which is useful information.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
The watchdog heartbeat timestamp is updated when the local heartbeat
timer fires (or touch_nmi_watchdog() is called).
This is an interesting data point, so don't overwrite it when the
soft-NMI interrupt detects a hard lockup. That code came from a pre-
merge version to prevent hard lockup messages flood, but that's taken
care of with the stuck CPU logic now, so there is no reason to
update the heartbeat timestamp here.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
The kexec_state KEXEC_STATE_IRQS_OFF barrier is reached by all
secondary CPUs before the kexec_cpu_down() operation is called on
secondaries. This can raise conflicts and provoque errors in the XIVE
hcalls when XIVE is shutdown with H_INT_RESET on the primary CPU.
To synchronize the kexec_cpu_down() operations and make sure the
secondaries have completed their task before the primary starts doing
the same, let's move the primary kexec_cpu_down() after the
KEXEC_STATE_REAL_MODE barrier.
This change of the ending sequence of kexec is mostly useful on the
pseries platform but it impacts also the powernv, ps3 and 85xx
platforms. powernv can be easily tested and fixed but some caution is
required for the other two.
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Unregister fadump on kexec down path otherwise the fadump registration
in new kexec-ed kernel complains that fadump is already registered.
This makes new kernel to continue using fadump registered by previous
kernel which may lead to invalid vmcore generation. Hence this patch
fixes this issue by un-registering fadump in fadump_cleanup() which is
called during kexec path so that new kernel can register fadump with
new valid values.
Fixes: b500afff11 ("fadump: Invalidate registration and release reserved memory for general use.")
Cc: stable@vger.kernel.org # v3.4+
Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
FADump capture kernel boots in restricted memory environment preserving
the context of previous kernel to save vmcore. Supporting hugepages in
such environment makes things unnecessarily complicated, as hugepages
need memory set aside for them. This means most of the capture kernel's
memory is used in supporting hugepages. In most cases, this results in
out-of-memory issues while booting FADump capture kernel. But hugepages
are not of much use in capture kernel whose only job is to save vmcore.
So, disabling hugepages support, when fadump is active, is a reliable
solution for the out of memory issues. Introducing a flag variable to
disable HugeTLB support when fadump is active.
Signed-off-by: Hari Bathini <hbathini@linux.vnet.ibm.com>
Reviewed-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
The second kernel, during early boot after the crash, reserves rest of
the memory above boot memory size to make sure it does not touch any of the
dump memory area. It uses memblock_reserve() that reserves the specified
memory region irrespective of memory holes present within that region.
There are chances where previous kernel would have hot removed some of
its memory leaving memory holes behind. In such cases fadump kernel reports
incorrect number of reserved pages through arch_reserved_kernel_pages()
hook causing kernel to hang or panic.
Fix this by excluding memory holes while reserving rest of the memory
above boot memory size during second kernel boot after crash.
Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Signed-off-by: Hari Bathini <hbathini@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
We've had dynamic ftrace support for over 9 years since Steve first
wrote it, all the distros use dynamic, and static is basically
untested these days, so drop support for static ftrace.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
With -mprofile-kernel, we always save the full register state in
ftrace_caller(). While this works, this is inefficient if we're not
interested in the register state, such as when we're using the function
tracer.
Rename the existing ftrace_caller() as ftrace_regs_caller() and provide
a simpler implementation for ftrace_caller() that is used when registers
are not required to be saved.
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Our implementation matches that of the generic version, which also
handles FTRACE_UPDATE_MODIFY_CALL. So, remove our implementation in
favor of the generic version.
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
For R_PPC64_REL24 relocations, we suppress emitting instructions for TOC
load/restore in the relocation stub if the relocation is for _mcount()
call when using -mprofile-kernel ABI.
To detect this, we check if the preceding instructions are per the
standard set of instructions emitted by gcc: either the two instruction
sequence of 'mflr r0; std r0,16(r1)', or the more optimized variant of a
single 'mflr r0'. This is not sufficient since nothing prevents users
from hand coding sequences involving a 'mflr r0' followed by a 'bl'.
For removing the toc save instruction from the stub, we additionally
check if the symbol is "_mcount". Add the same check here as well.
Also rename is_early_mcount_callsite() to is_mprofile_mcount_callsite()
since that is what is being checked. The use of "early" is misleading
since there is nothing involving this function that qualifies as early.
Fixes: 153086644f ("powerpc/ftrace: Add support for -mprofile-kernel ftrace ABI")
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
