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linux/arch/x86/lib/copy_user_64.S

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x86: fix copy_user on x86 Switch copy_user_generic_string(), copy_user_generic_unrolled() and __copy_user_nocache() from custom tail handlers to generic copy_user_tail_handle(). Signed-off-by: Vitaly Mayatskikh <v.mayatskih@gmail.com> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-02 13:53:13 +00:00
/*
* Copyright 2008 Vitaly Mayatskikh <vmayatsk@redhat.com>
* Copyright 2002 Andi Kleen, SuSE Labs.
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 22:20:36 +00:00
* Subject to the GNU Public License v2.
x86: fix copy_user on x86 Switch copy_user_generic_string(), copy_user_generic_unrolled() and __copy_user_nocache() from custom tail handlers to generic copy_user_tail_handle(). Signed-off-by: Vitaly Mayatskikh <v.mayatskih@gmail.com> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-02 13:53:13 +00:00
*
* Functions to copy from and to user space.
*/
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 22:20:36 +00:00
[PATCH] annotate arch/x86_64/lib/*.S Add unwind annotations to arch/x86_64/lib/*.S, and also use the macros provided by linux/linkage.h where-ever possible. Some of the alternative instructions handling needed to be adjusted so that the replacement code would also have valid unwind information. Signed-off-by: Jan Beulich <jbeulich@novell.com> Signed-off-by: Andi Kleen <ak@suse.de>
2006-09-26 08:52:32 +00:00
#include <linux/linkage.h>
#include <asm/dwarf2.h>
[PATCH] Fix zeroing on exception in copy_*_user - Don't zero for __copy_from_user_inatomic following i386. This will prevent spurious zeros for parallel file system writers when one does a exception - The string instruction version didn't zero the output on exception. Oops. Also I cleaned up the code a bit while I was at it and added a minor optimization to the string instruction path. Signed-off-by: Andi Kleen <ak@suse.de>
2006-09-26 08:52:39 +00:00
#include <asm/current.h>
#include <asm/asm-offsets.h>
#include <asm/thread_info.h>
#include <asm/cpufeature.h>
x86, mem: copy_user_64.S: Support copy_to/from_user by enhanced REP MOVSB/STOSB Support copy_to_user/copy_from_user() by enhanced REP MOVSB/STOSB. On processors supporting enhanced REP MOVSB/STOSB, the alternative copy_user_enhanced_fast_string function using enhanced rep movsb overrides the original function and the fast string function. Signed-off-by: Fenghua Yu <fenghua.yu@intel.com> Link: http://lkml.kernel.org/r/1305671358-14478-7-git-send-email-fenghua.yu@intel.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2011-05-17 22:29:15 +00:00
#include <asm/alternative-asm.h>
x86, extable: Remove open-coded exception table entries in arch/x86/lib/copy_user_64.S Remove open-coded exception table entries in arch/x86/lib/copy_user_64.S, and replace them with _ASM_EXTABLE() macros; this will allow us to change the format and type of the exception table entries. Signed-off-by: H. Peter Anvin <hpa@zytor.com> Cc: David Daney <david.daney@cavium.com> Link: http://lkml.kernel.org/r/CA%2B55aFyijf43qSu3N9nWHEBwaGbb7T2Oq9A=9EyR=Jtyqfq_cQ@mail.gmail.com
2012-04-20 19:19:51 +00:00
#include <asm/asm.h>
x86, smap: Add STAC and CLAC instructions to control user space access When Supervisor Mode Access Prevention (SMAP) is enabled, access to userspace from the kernel is controlled by the AC flag. To make the performance of manipulating that flag acceptable, there are two new instructions, STAC and CLAC, to set and clear it. This patch adds those instructions, via alternative(), when the SMAP feature is enabled. It also adds X86_EFLAGS_AC unconditionally to the SYSCALL entry mask; there is simply no reason to make that one conditional. Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Link: http://lkml.kernel.org/r/1348256595-29119-9-git-send-email-hpa@linux.intel.com
2012-09-21 19:43:12 +00:00
#include <asm/smap.h>
[PATCH] Fix zeroing on exception in copy_*_user - Don't zero for __copy_from_user_inatomic following i386. This will prevent spurious zeros for parallel file system writers when one does a exception - The string instruction version didn't zero the output on exception. Oops. Also I cleaned up the code a bit while I was at it and added a minor optimization to the string instruction path. Signed-off-by: Andi Kleen <ak@suse.de>
2006-09-26 08:52:39 +00:00
x86, mem: copy_user_64.S: Support copy_to/from_user by enhanced REP MOVSB/STOSB Support copy_to_user/copy_from_user() by enhanced REP MOVSB/STOSB. On processors supporting enhanced REP MOVSB/STOSB, the alternative copy_user_enhanced_fast_string function using enhanced rep movsb overrides the original function and the fast string function. Signed-off-by: Fenghua Yu <fenghua.yu@intel.com> Link: http://lkml.kernel.org/r/1305671358-14478-7-git-send-email-fenghua.yu@intel.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2011-05-17 22:29:15 +00:00
/*
* By placing feature2 after feature1 in altinstructions section, we logically
* implement:
* If CPU has feature2, jmp to alt2 is used
* else if CPU has feature1, jmp to alt1 is used
* else jmp to orig is used.
*/
.macro ALTERNATIVE_JUMP feature1,feature2,orig,alt1,alt2
[PATCH] Fix zeroing on exception in copy_*_user - Don't zero for __copy_from_user_inatomic following i386. This will prevent spurious zeros for parallel file system writers when one does a exception - The string instruction version didn't zero the output on exception. Oops. Also I cleaned up the code a bit while I was at it and added a minor optimization to the string instruction path. Signed-off-by: Andi Kleen <ak@suse.de>
2006-09-26 08:52:39 +00:00
0:
x86/alternatives: Make JMPs more robust Up until now we had to pay attention to relative JMPs in alternatives about how their relative offset gets computed so that the jump target is still correct. Or, as it is the case for near CALLs (opcode e8), we still have to go and readjust the offset at patching time. What is more, the static_cpu_has_safe() facility had to forcefully generate 5-byte JMPs since we couldn't rely on the compiler to generate properly sized ones so we had to force the longest ones. Worse than that, sometimes it would generate a replacement JMP which is longer than the original one, thus overwriting the beginning of the next instruction at patching time. So, in order to alleviate all that and make using JMPs more straight-forward we go and pad the original instruction in an alternative block with NOPs at build time, should the replacement(s) be longer. This way, alternatives users shouldn't pay special attention so that original and replacement instruction sizes are fine but the assembler would simply add padding where needed and not do anything otherwise. As a second aspect, we go and recompute JMPs at patching time so that we can try to make 5-byte JMPs into two-byte ones if possible. If not, we still have to recompute the offsets as the replacement JMP gets put far away in the .altinstr_replacement section leading to a wrong offset if copied verbatim. For example, on a locally generated kernel image old insn VA: 0xffffffff810014bd, CPU feat: X86_FEATURE_ALWAYS, size: 2 __switch_to: ffffffff810014bd: eb 21 jmp ffffffff810014e0 repl insn: size: 5 ffffffff81d0b23c: e9 b1 62 2f ff jmpq ffffffff810014f2 gets corrected to a 2-byte JMP: apply_alternatives: feat: 3*32+21, old: (ffffffff810014bd, len: 2), repl: (ffffffff81d0b23c, len: 5) alt_insn: e9 b1 62 2f ff recompute_jumps: next_rip: ffffffff81d0b241, tgt_rip: ffffffff810014f2, new_displ: 0x00000033, ret len: 2 converted to: eb 33 90 90 90 and a 5-byte JMP: old insn VA: 0xffffffff81001516, CPU feat: X86_FEATURE_ALWAYS, size: 2 __switch_to: ffffffff81001516: eb 30 jmp ffffffff81001548 repl insn: size: 5 ffffffff81d0b241: e9 10 63 2f ff jmpq ffffffff81001556 gets shortened into a two-byte one: apply_alternatives: feat: 3*32+21, old: (ffffffff81001516, len: 2), repl: (ffffffff81d0b241, len: 5) alt_insn: e9 10 63 2f ff recompute_jumps: next_rip: ffffffff81d0b246, tgt_rip: ffffffff81001556, new_displ: 0x0000003e, ret len: 2 converted to: eb 3e 90 90 90 ... and so on. This leads to a net win of around 40ish replacements * 3 bytes savings =~ 120 bytes of I$ on an AMD guest which means some savings of precious instruction cache bandwidth. The padding to the shorter 2-byte JMPs are single-byte NOPs which on smart microarchitectures means discarding NOPs at decode time and thus freeing up execution bandwidth. Signed-off-by: Borislav Petkov <bp@suse.de>
2015-01-05 12:48:41 +00:00
jmp \orig
[PATCH] Fix zeroing on exception in copy_*_user - Don't zero for __copy_from_user_inatomic following i386. This will prevent spurious zeros for parallel file system writers when one does a exception - The string instruction version didn't zero the output on exception. Oops. Also I cleaned up the code a bit while I was at it and added a minor optimization to the string instruction path. Signed-off-by: Andi Kleen <ak@suse.de>
2006-09-26 08:52:39 +00:00
1:
.section .altinstr_replacement,"ax"
x86/alternatives: Make JMPs more robust Up until now we had to pay attention to relative JMPs in alternatives about how their relative offset gets computed so that the jump target is still correct. Or, as it is the case for near CALLs (opcode e8), we still have to go and readjust the offset at patching time. What is more, the static_cpu_has_safe() facility had to forcefully generate 5-byte JMPs since we couldn't rely on the compiler to generate properly sized ones so we had to force the longest ones. Worse than that, sometimes it would generate a replacement JMP which is longer than the original one, thus overwriting the beginning of the next instruction at patching time. So, in order to alleviate all that and make using JMPs more straight-forward we go and pad the original instruction in an alternative block with NOPs at build time, should the replacement(s) be longer. This way, alternatives users shouldn't pay special attention so that original and replacement instruction sizes are fine but the assembler would simply add padding where needed and not do anything otherwise. As a second aspect, we go and recompute JMPs at patching time so that we can try to make 5-byte JMPs into two-byte ones if possible. If not, we still have to recompute the offsets as the replacement JMP gets put far away in the .altinstr_replacement section leading to a wrong offset if copied verbatim. For example, on a locally generated kernel image old insn VA: 0xffffffff810014bd, CPU feat: X86_FEATURE_ALWAYS, size: 2 __switch_to: ffffffff810014bd: eb 21 jmp ffffffff810014e0 repl insn: size: 5 ffffffff81d0b23c: e9 b1 62 2f ff jmpq ffffffff810014f2 gets corrected to a 2-byte JMP: apply_alternatives: feat: 3*32+21, old: (ffffffff810014bd, len: 2), repl: (ffffffff81d0b23c, len: 5) alt_insn: e9 b1 62 2f ff recompute_jumps: next_rip: ffffffff81d0b241, tgt_rip: ffffffff810014f2, new_displ: 0x00000033, ret len: 2 converted to: eb 33 90 90 90 and a 5-byte JMP: old insn VA: 0xffffffff81001516, CPU feat: X86_FEATURE_ALWAYS, size: 2 __switch_to: ffffffff81001516: eb 30 jmp ffffffff81001548 repl insn: size: 5 ffffffff81d0b241: e9 10 63 2f ff jmpq ffffffff81001556 gets shortened into a two-byte one: apply_alternatives: feat: 3*32+21, old: (ffffffff81001516, len: 2), repl: (ffffffff81d0b241, len: 5) alt_insn: e9 10 63 2f ff recompute_jumps: next_rip: ffffffff81d0b246, tgt_rip: ffffffff81001556, new_displ: 0x0000003e, ret len: 2 converted to: eb 3e 90 90 90 ... and so on. This leads to a net win of around 40ish replacements * 3 bytes savings =~ 120 bytes of I$ on an AMD guest which means some savings of precious instruction cache bandwidth. The padding to the shorter 2-byte JMPs are single-byte NOPs which on smart microarchitectures means discarding NOPs at decode time and thus freeing up execution bandwidth. Signed-off-by: Borislav Petkov <bp@suse.de>
2015-01-05 12:48:41 +00:00
2:
jmp \alt1
3:
jmp \alt2
[PATCH] Fix zeroing on exception in copy_*_user - Don't zero for __copy_from_user_inatomic following i386. This will prevent spurious zeros for parallel file system writers when one does a exception - The string instruction version didn't zero the output on exception. Oops. Also I cleaned up the code a bit while I was at it and added a minor optimization to the string instruction path. Signed-off-by: Andi Kleen <ak@suse.de>
2006-09-26 08:52:39 +00:00
.previous
x86, mem: copy_user_64.S: Support copy_to/from_user by enhanced REP MOVSB/STOSB Support copy_to_user/copy_from_user() by enhanced REP MOVSB/STOSB. On processors supporting enhanced REP MOVSB/STOSB, the alternative copy_user_enhanced_fast_string function using enhanced rep movsb overrides the original function and the fast string function. Signed-off-by: Fenghua Yu <fenghua.yu@intel.com> Link: http://lkml.kernel.org/r/1305671358-14478-7-git-send-email-fenghua.yu@intel.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2011-05-17 22:29:15 +00:00
[PATCH] Fix zeroing on exception in copy_*_user - Don't zero for __copy_from_user_inatomic following i386. This will prevent spurious zeros for parallel file system writers when one does a exception - The string instruction version didn't zero the output on exception. Oops. Also I cleaned up the code a bit while I was at it and added a minor optimization to the string instruction path. Signed-off-by: Andi Kleen <ak@suse.de>
2006-09-26 08:52:39 +00:00
.section .altinstructions,"a"
x86/alternatives: Add instruction padding Up until now we have always paid attention to make sure the length of the new instruction replacing the old one is at least less or equal to the length of the old instruction. If the new instruction is longer, at the time it replaces the old instruction it will overwrite the beginning of the next instruction in the kernel image and cause your pants to catch fire. So instead of having to pay attention, teach the alternatives framework to pad shorter old instructions with NOPs at buildtime - but only in the case when len(old instruction(s)) < len(new instruction(s)) and add nothing in the >= case. (In that case we do add_nops() when patching). This way the alternatives user shouldn't have to care about instruction sizes and simply use the macros. Add asm ALTERNATIVE* flavor macros too, while at it. Also, we need to save the pad length in a separate struct alt_instr member for NOP optimization and the way to do that reliably is to carry the pad length instead of trying to detect whether we're looking at single-byte NOPs or at pathological instruction offsets like e9 90 90 90 90, for example, which is a valid instruction. Thanks to Michael Matz for the great help with toolchain questions. Signed-off-by: Borislav Petkov <bp@suse.de>
2014-12-27 09:41:52 +00:00
altinstruction_entry 0b,2b,\feature1,5,5,0
altinstruction_entry 0b,3b,\feature2,5,5,0
[PATCH] Fix zeroing on exception in copy_*_user - Don't zero for __copy_from_user_inatomic following i386. This will prevent spurious zeros for parallel file system writers when one does a exception - The string instruction version didn't zero the output on exception. Oops. Also I cleaned up the code a bit while I was at it and added a minor optimization to the string instruction path. Signed-off-by: Andi Kleen <ak@suse.de>
2006-09-26 08:52:39 +00:00
.previous
.endm
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 22:20:36 +00:00
x86: fix copy_user on x86 Switch copy_user_generic_string(), copy_user_generic_unrolled() and __copy_user_nocache() from custom tail handlers to generic copy_user_tail_handle(). Signed-off-by: Vitaly Mayatskikh <v.mayatskih@gmail.com> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-02 13:53:13 +00:00
.macro ALIGN_DESTINATION
/* check for bad alignment of destination */
movl %edi,%ecx
andl $7,%ecx
jz 102f /* already aligned */
subl $8,%ecx
negl %ecx
subl %ecx,%edx
100: movb (%rsi),%al
101: movb %al,(%rdi)
incq %rsi
incq %rdi
decl %ecx
jnz 100b
102:
.section .fixup,"ax"
x86: wrong register was used in align macro New ALIGN_DESTINATION macro has sad typo: r8d register was used instead of ecx in fixup section. This can be considered as a regression. Register ecx was also wrongly loaded with value in r8d in copy_user_nocache routine. Signed-off-by: Vitaly Mayatskikh <v.mayatskih@gmail.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-30 11:30:14 +00:00
103: addl %ecx,%edx /* ecx is zerorest also */
x86: fix copy_user on x86 Switch copy_user_generic_string(), copy_user_generic_unrolled() and __copy_user_nocache() from custom tail handlers to generic copy_user_tail_handle(). Signed-off-by: Vitaly Mayatskikh <v.mayatskih@gmail.com> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-02 13:53:13 +00:00
jmp copy_user_handle_tail
.previous
x86, extable: Remove open-coded exception table entries in arch/x86/lib/copy_user_64.S Remove open-coded exception table entries in arch/x86/lib/copy_user_64.S, and replace them with _ASM_EXTABLE() macros; this will allow us to change the format and type of the exception table entries. Signed-off-by: H. Peter Anvin <hpa@zytor.com> Cc: David Daney <david.daney@cavium.com> Link: http://lkml.kernel.org/r/CA%2B55aFyijf43qSu3N9nWHEBwaGbb7T2Oq9A=9EyR=Jtyqfq_cQ@mail.gmail.com
2012-04-20 19:19:51 +00:00
_ASM_EXTABLE(100b,103b)
_ASM_EXTABLE(101b,103b)
x86: fix copy_user on x86 Switch copy_user_generic_string(), copy_user_generic_unrolled() and __copy_user_nocache() from custom tail handlers to generic copy_user_tail_handle(). Signed-off-by: Vitaly Mayatskikh <v.mayatskih@gmail.com> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-02 13:53:13 +00:00
.endm
/* Standard copy_to_user with segment limit checking */
x86: Add missing might_fault() checks to copy_{to,from}_user() On x86-64, copy_[to|from]_user() rely on assembly routines that never call might_fault(), making us missing various lockdep checks. This doesn't apply to __copy_from,to_user() that explicitly handle these calls, neither is it a problem in x86-32 where copy_to,from_user() rely on the "__" prefixed versions that also call might_fault(). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Arjan van de Ven <arjan@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Nick Piggin <npiggin@suse.de> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> LKML-Reference: <1258382538-30979-1-git-send-email-fweisbec@gmail.com> [ v2: fix module export ] Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-16 14:42:18 +00:00
ENTRY(_copy_to_user)
[PATCH] annotate arch/x86_64/lib/*.S Add unwind annotations to arch/x86_64/lib/*.S, and also use the macros provided by linux/linkage.h where-ever possible. Some of the alternative instructions handling needed to be adjusted so that the replacement code would also have valid unwind information. Signed-off-by: Jan Beulich <jbeulich@novell.com> Signed-off-by: Andi Kleen <ak@suse.de>
2006-09-26 08:52:32 +00:00
CFI_STARTPROC
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 22:20:36 +00:00
GET_THREAD_INFO(%rax)
movq %rdi,%rcx
addq %rdx,%rcx
x86: fix copy_user on x86 Switch copy_user_generic_string(), copy_user_generic_unrolled() and __copy_user_nocache() from custom tail handlers to generic copy_user_tail_handle(). Signed-off-by: Vitaly Mayatskikh <v.mayatskih@gmail.com> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-02 13:53:13 +00:00
jc bad_to_user
x86: rename threadinfo to TI. This is for consistency with i386. Signed-off-by: Glauber Costa <gcosta@redhat.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-06-24 14:19:35 +00:00
cmpq TI_addr_limit(%rax),%rcx
x86, 64-bit: Fix copy_[to/from]_user() checks for the userspace address limit As reported in BZ #30352: https://bugzilla.kernel.org/show_bug.cgi?id=30352 there's a kernel bug related to reading the last allowed page on x86_64. The _copy_to_user() and _copy_from_user() functions use the following check for address limit: if (buf + size >= limit) fail(); while it should be more permissive: if (buf + size > limit) fail(); That's because the size represents the number of bytes being read/write from/to buf address AND including the buf address. So the copy function will actually never touch the limit address even if "buf + size == limit". Following program fails to use the last page as buffer due to the wrong limit check: #include <sys/mman.h> #include <sys/socket.h> #include <assert.h> #define PAGE_SIZE (4096) #define LAST_PAGE ((void*)(0x7fffffffe000)) int main() { int fds[2], err; void * ptr = mmap(LAST_PAGE, PAGE_SIZE, PROT_READ | PROT_WRITE, MAP_ANONYMOUS | MAP_PRIVATE | MAP_FIXED, -1, 0); assert(ptr == LAST_PAGE); err = socketpair(AF_LOCAL, SOCK_STREAM, 0, fds); assert(err == 0); err = send(fds[0], ptr, PAGE_SIZE, 0); perror("send"); assert(err == PAGE_SIZE); err = recv(fds[1], ptr, PAGE_SIZE, MSG_WAITALL); perror("recv"); assert(err == PAGE_SIZE); return 0; } The other place checking the addr limit is the access_ok() function, which is working properly. There's just a misleading comment for the __range_not_ok() macro - which this patch fixes as well. The last page of the user-space address range is a guard page and Brian Gerst observed that the guard page itself due to an erratum on K8 cpus (#121 Sequential Execution Across Non-Canonical Boundary Causes Processor Hang). However, the test code is using the last valid page before the guard page. The bug is that the last byte before the guard page can't be read because of the off-by-one error. The guard page is left in place. This bug would normally not show up because the last page is part of the process stack and never accessed via syscalls. Signed-off-by: Jiri Olsa <jolsa@redhat.com> Acked-by: Brian Gerst <brgerst@gmail.com> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: <stable@kernel.org> Link: http://lkml.kernel.org/r/1305210630-7136-1-git-send-email-jolsa@redhat.com Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-05-12 14:30:30 +00:00
ja bad_to_user
x86, mem: copy_user_64.S: Support copy_to/from_user by enhanced REP MOVSB/STOSB Support copy_to_user/copy_from_user() by enhanced REP MOVSB/STOSB. On processors supporting enhanced REP MOVSB/STOSB, the alternative copy_user_enhanced_fast_string function using enhanced rep movsb overrides the original function and the fast string function. Signed-off-by: Fenghua Yu <fenghua.yu@intel.com> Link: http://lkml.kernel.org/r/1305671358-14478-7-git-send-email-fenghua.yu@intel.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2011-05-17 22:29:15 +00:00
ALTERNATIVE_JUMP X86_FEATURE_REP_GOOD,X86_FEATURE_ERMS, \
copy_user_generic_unrolled,copy_user_generic_string, \
copy_user_enhanced_fast_string
[PATCH] annotate arch/x86_64/lib/*.S Add unwind annotations to arch/x86_64/lib/*.S, and also use the macros provided by linux/linkage.h where-ever possible. Some of the alternative instructions handling needed to be adjusted so that the replacement code would also have valid unwind information. Signed-off-by: Jan Beulich <jbeulich@novell.com> Signed-off-by: Andi Kleen <ak@suse.de>
2006-09-26 08:52:32 +00:00
CFI_ENDPROC
x86: Add missing might_fault() checks to copy_{to,from}_user() On x86-64, copy_[to|from]_user() rely on assembly routines that never call might_fault(), making us missing various lockdep checks. This doesn't apply to __copy_from,to_user() that explicitly handle these calls, neither is it a problem in x86-32 where copy_to,from_user() rely on the "__" prefixed versions that also call might_fault(). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Arjan van de Ven <arjan@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Nick Piggin <npiggin@suse.de> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> LKML-Reference: <1258382538-30979-1-git-send-email-fweisbec@gmail.com> [ v2: fix module export ] Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-16 14:42:18 +00:00
ENDPROC(_copy_to_user)
[PATCH] x86_64: Undo the earlier changes to remove unrolled copy/memset functions They cause quite bad performance regressions on Netburst This is temporary until we can get new optimized functions for these CPUs. This undoes changes that were done in 2.6.15 and in 2.6.16-rc1, essentially bringing the code back to 2.6.14 level. Only change is I renamed the X86_FEATURE_K8_C flag to X86_FEATURE_REP_GOOD and fixed the check for the flag and also fixed some comments. Signed-off-by: Andi Kleen <ak@suse.de> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-03 20:51:02 +00:00
x86: fix copy_user on x86 Switch copy_user_generic_string(), copy_user_generic_unrolled() and __copy_user_nocache() from custom tail handlers to generic copy_user_tail_handle(). Signed-off-by: Vitaly Mayatskikh <v.mayatskih@gmail.com> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-02 13:53:13 +00:00
/* Standard copy_from_user with segment limit checking */
x86: Use __builtin_object_size() to validate the buffer size for copy_from_user() gcc (4.x) supports the __builtin_object_size() builtin, which reports the size of an object that a pointer point to, when known at compile time. If the buffer size is not known at compile time, a constant -1 is returned. This patch uses this feature to add a sanity check to copy_from_user(); if the target buffer is known to be smaller than the copy size, the copy is aborted and a WARNing is emitted in memory debug mode. These extra checks compile away when the object size is not known, or if both the buffer size and the copy length are constants. Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> LKML-Reference: <20090926143301.2c396b94@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-26 12:33:01 +00:00
ENTRY(_copy_from_user)
[PATCH] Fix zeroing on exception in copy_*_user - Don't zero for __copy_from_user_inatomic following i386. This will prevent spurious zeros for parallel file system writers when one does a exception - The string instruction version didn't zero the output on exception. Oops. Also I cleaned up the code a bit while I was at it and added a minor optimization to the string instruction path. Signed-off-by: Andi Kleen <ak@suse.de>
2006-09-26 08:52:39 +00:00
CFI_STARTPROC
x86: fix copy_user on x86 Switch copy_user_generic_string(), copy_user_generic_unrolled() and __copy_user_nocache() from custom tail handlers to generic copy_user_tail_handle(). Signed-off-by: Vitaly Mayatskikh <v.mayatskih@gmail.com> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-02 13:53:13 +00:00
GET_THREAD_INFO(%rax)
movq %rsi,%rcx
addq %rdx,%rcx
jc bad_from_user
cmpq TI_addr_limit(%rax),%rcx
x86, 64-bit: Fix copy_[to/from]_user() checks for the userspace address limit As reported in BZ #30352: https://bugzilla.kernel.org/show_bug.cgi?id=30352 there's a kernel bug related to reading the last allowed page on x86_64. The _copy_to_user() and _copy_from_user() functions use the following check for address limit: if (buf + size >= limit) fail(); while it should be more permissive: if (buf + size > limit) fail(); That's because the size represents the number of bytes being read/write from/to buf address AND including the buf address. So the copy function will actually never touch the limit address even if "buf + size == limit". Following program fails to use the last page as buffer due to the wrong limit check: #include <sys/mman.h> #include <sys/socket.h> #include <assert.h> #define PAGE_SIZE (4096) #define LAST_PAGE ((void*)(0x7fffffffe000)) int main() { int fds[2], err; void * ptr = mmap(LAST_PAGE, PAGE_SIZE, PROT_READ | PROT_WRITE, MAP_ANONYMOUS | MAP_PRIVATE | MAP_FIXED, -1, 0); assert(ptr == LAST_PAGE); err = socketpair(AF_LOCAL, SOCK_STREAM, 0, fds); assert(err == 0); err = send(fds[0], ptr, PAGE_SIZE, 0); perror("send"); assert(err == PAGE_SIZE); err = recv(fds[1], ptr, PAGE_SIZE, MSG_WAITALL); perror("recv"); assert(err == PAGE_SIZE); return 0; } The other place checking the addr limit is the access_ok() function, which is working properly. There's just a misleading comment for the __range_not_ok() macro - which this patch fixes as well. The last page of the user-space address range is a guard page and Brian Gerst observed that the guard page itself due to an erratum on K8 cpus (#121 Sequential Execution Across Non-Canonical Boundary Causes Processor Hang). However, the test code is using the last valid page before the guard page. The bug is that the last byte before the guard page can't be read because of the off-by-one error. The guard page is left in place. This bug would normally not show up because the last page is part of the process stack and never accessed via syscalls. Signed-off-by: Jiri Olsa <jolsa@redhat.com> Acked-by: Brian Gerst <brgerst@gmail.com> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: <stable@kernel.org> Link: http://lkml.kernel.org/r/1305210630-7136-1-git-send-email-jolsa@redhat.com Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-05-12 14:30:30 +00:00
ja bad_from_user
x86, mem: copy_user_64.S: Support copy_to/from_user by enhanced REP MOVSB/STOSB Support copy_to_user/copy_from_user() by enhanced REP MOVSB/STOSB. On processors supporting enhanced REP MOVSB/STOSB, the alternative copy_user_enhanced_fast_string function using enhanced rep movsb overrides the original function and the fast string function. Signed-off-by: Fenghua Yu <fenghua.yu@intel.com> Link: http://lkml.kernel.org/r/1305671358-14478-7-git-send-email-fenghua.yu@intel.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2011-05-17 22:29:15 +00:00
ALTERNATIVE_JUMP X86_FEATURE_REP_GOOD,X86_FEATURE_ERMS, \
copy_user_generic_unrolled,copy_user_generic_string, \
copy_user_enhanced_fast_string
[PATCH] Fix zeroing on exception in copy_*_user - Don't zero for __copy_from_user_inatomic following i386. This will prevent spurious zeros for parallel file system writers when one does a exception - The string instruction version didn't zero the output on exception. Oops. Also I cleaned up the code a bit while I was at it and added a minor optimization to the string instruction path. Signed-off-by: Andi Kleen <ak@suse.de>
2006-09-26 08:52:39 +00:00
CFI_ENDPROC
x86: Use __builtin_object_size() to validate the buffer size for copy_from_user() gcc (4.x) supports the __builtin_object_size() builtin, which reports the size of an object that a pointer point to, when known at compile time. If the buffer size is not known at compile time, a constant -1 is returned. This patch uses this feature to add a sanity check to copy_from_user(); if the target buffer is known to be smaller than the copy size, the copy is aborted and a WARNing is emitted in memory debug mode. These extra checks compile away when the object size is not known, or if both the buffer size and the copy length are constants. Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> LKML-Reference: <20090926143301.2c396b94@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-26 12:33:01 +00:00
ENDPROC(_copy_from_user)
[PATCH] Fix zeroing on exception in copy_*_user - Don't zero for __copy_from_user_inatomic following i386. This will prevent spurious zeros for parallel file system writers when one does a exception - The string instruction version didn't zero the output on exception. Oops. Also I cleaned up the code a bit while I was at it and added a minor optimization to the string instruction path. Signed-off-by: Andi Kleen <ak@suse.de>
2006-09-26 08:52:39 +00:00
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 22:20:36 +00:00
.section .fixup,"ax"
/* must zero dest */
x86: fix copy_user on x86 Switch copy_user_generic_string(), copy_user_generic_unrolled() and __copy_user_nocache() from custom tail handlers to generic copy_user_tail_handle(). Signed-off-by: Vitaly Mayatskikh <v.mayatskih@gmail.com> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-02 13:53:13 +00:00
ENTRY(bad_from_user)
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 22:20:36 +00:00
bad_from_user:
[PATCH] annotate arch/x86_64/lib/*.S Add unwind annotations to arch/x86_64/lib/*.S, and also use the macros provided by linux/linkage.h where-ever possible. Some of the alternative instructions handling needed to be adjusted so that the replacement code would also have valid unwind information. Signed-off-by: Jan Beulich <jbeulich@novell.com> Signed-off-by: Andi Kleen <ak@suse.de>
2006-09-26 08:52:32 +00:00
CFI_STARTPROC
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 22:20:36 +00:00
movl %edx,%ecx
xorl %eax,%eax
rep
stosb
bad_to_user:
x86: fix copy_user on x86 Switch copy_user_generic_string(), copy_user_generic_unrolled() and __copy_user_nocache() from custom tail handlers to generic copy_user_tail_handle(). Signed-off-by: Vitaly Mayatskikh <v.mayatskih@gmail.com> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-02 13:53:13 +00:00
movl %edx,%eax
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 22:20:36 +00:00
ret
[PATCH] annotate arch/x86_64/lib/*.S Add unwind annotations to arch/x86_64/lib/*.S, and also use the macros provided by linux/linkage.h where-ever possible. Some of the alternative instructions handling needed to be adjusted so that the replacement code would also have valid unwind information. Signed-off-by: Jan Beulich <jbeulich@novell.com> Signed-off-by: Andi Kleen <ak@suse.de>
2006-09-26 08:52:32 +00:00
CFI_ENDPROC
x86: fix copy_user on x86 Switch copy_user_generic_string(), copy_user_generic_unrolled() and __copy_user_nocache() from custom tail handlers to generic copy_user_tail_handle(). Signed-off-by: Vitaly Mayatskikh <v.mayatskih@gmail.com> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-02 13:53:13 +00:00
ENDPROC(bad_from_user)
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 22:20:36 +00:00
.previous
x86: fix copy_user on x86 Switch copy_user_generic_string(), copy_user_generic_unrolled() and __copy_user_nocache() from custom tail handlers to generic copy_user_tail_handle(). Signed-off-by: Vitaly Mayatskikh <v.mayatskih@gmail.com> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-02 13:53:13 +00:00
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 22:20:36 +00:00
/*
[PATCH] Fix zeroing on exception in copy_*_user - Don't zero for __copy_from_user_inatomic following i386. This will prevent spurious zeros for parallel file system writers when one does a exception - The string instruction version didn't zero the output on exception. Oops. Also I cleaned up the code a bit while I was at it and added a minor optimization to the string instruction path. Signed-off-by: Andi Kleen <ak@suse.de>
2006-09-26 08:52:39 +00:00
* copy_user_generic_unrolled - memory copy with exception handling.
x86: fix copy_user on x86 Switch copy_user_generic_string(), copy_user_generic_unrolled() and __copy_user_nocache() from custom tail handlers to generic copy_user_tail_handle(). Signed-off-by: Vitaly Mayatskikh <v.mayatskih@gmail.com> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-02 13:53:13 +00:00
* This version is for CPUs like P4 that don't have efficient micro
* code for rep movsq
*
* Input:
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 22:20:36 +00:00
* rdi destination
* rsi source
* rdx count
*
x86: fix copy_user on x86 Switch copy_user_generic_string(), copy_user_generic_unrolled() and __copy_user_nocache() from custom tail handlers to generic copy_user_tail_handle(). Signed-off-by: Vitaly Mayatskikh <v.mayatskih@gmail.com> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-02 13:53:13 +00:00
* Output:
x86: Fix common misspellings They were generated by 'codespell' and then manually reviewed. Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi> Cc: trivial@kernel.org LKML-Reference: <1300389856-1099-3-git-send-email-lucas.demarchi@profusion.mobi> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-03-17 19:24:16 +00:00
* eax uncopied bytes or 0 if successful.
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 22:20:36 +00:00
*/
[PATCH] Fix zeroing on exception in copy_*_user - Don't zero for __copy_from_user_inatomic following i386. This will prevent spurious zeros for parallel file system writers when one does a exception - The string instruction version didn't zero the output on exception. Oops. Also I cleaned up the code a bit while I was at it and added a minor optimization to the string instruction path. Signed-off-by: Andi Kleen <ak@suse.de>
2006-09-26 08:52:39 +00:00
ENTRY(copy_user_generic_unrolled)
[PATCH] annotate arch/x86_64/lib/*.S Add unwind annotations to arch/x86_64/lib/*.S, and also use the macros provided by linux/linkage.h where-ever possible. Some of the alternative instructions handling needed to be adjusted so that the replacement code would also have valid unwind information. Signed-off-by: Jan Beulich <jbeulich@novell.com> Signed-off-by: Andi Kleen <ak@suse.de>
2006-09-26 08:52:32 +00:00
CFI_STARTPROC
x86, smap: Add STAC and CLAC instructions to control user space access When Supervisor Mode Access Prevention (SMAP) is enabled, access to userspace from the kernel is controlled by the AC flag. To make the performance of manipulating that flag acceptable, there are two new instructions, STAC and CLAC, to set and clear it. This patch adds those instructions, via alternative(), when the SMAP feature is enabled. It also adds X86_EFLAGS_AC unconditionally to the SYSCALL entry mask; there is simply no reason to make that one conditional. Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Link: http://lkml.kernel.org/r/1348256595-29119-9-git-send-email-hpa@linux.intel.com
2012-09-21 19:43:12 +00:00
ASM_STAC
x86: fix copy_user on x86 Switch copy_user_generic_string(), copy_user_generic_unrolled() and __copy_user_nocache() from custom tail handlers to generic copy_user_tail_handle(). Signed-off-by: Vitaly Mayatskikh <v.mayatskih@gmail.com> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-02 13:53:13 +00:00
cmpl $8,%edx
jb 20f /* less then 8 bytes, go to byte copy loop */
ALIGN_DESTINATION
movl %edx,%ecx
andl $63,%edx
shrl $6,%ecx
jz 17f
1: movq (%rsi),%r8
2: movq 1*8(%rsi),%r9
3: movq 2*8(%rsi),%r10
4: movq 3*8(%rsi),%r11
5: movq %r8,(%rdi)
6: movq %r9,1*8(%rdi)
7: movq %r10,2*8(%rdi)
8: movq %r11,3*8(%rdi)
9: movq 4*8(%rsi),%r8
10: movq 5*8(%rsi),%r9
11: movq 6*8(%rsi),%r10
12: movq 7*8(%rsi),%r11
13: movq %r8,4*8(%rdi)
14: movq %r9,5*8(%rdi)
15: movq %r10,6*8(%rdi)
16: movq %r11,7*8(%rdi)
[PATCH] x86_64: Undo the earlier changes to remove unrolled copy/memset functions They cause quite bad performance regressions on Netburst This is temporary until we can get new optimized functions for these CPUs. This undoes changes that were done in 2.6.15 and in 2.6.16-rc1, essentially bringing the code back to 2.6.14 level. Only change is I renamed the X86_FEATURE_K8_C flag to X86_FEATURE_REP_GOOD and fixed the check for the flag and also fixed some comments. Signed-off-by: Andi Kleen <ak@suse.de> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-03 20:51:02 +00:00
leaq 64(%rsi),%rsi
leaq 64(%rdi),%rdi
decl %ecx
x86: fix copy_user on x86 Switch copy_user_generic_string(), copy_user_generic_unrolled() and __copy_user_nocache() from custom tail handlers to generic copy_user_tail_handle(). Signed-off-by: Vitaly Mayatskikh <v.mayatskih@gmail.com> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-02 13:53:13 +00:00
jnz 1b
17: movl %edx,%ecx
andl $7,%edx
shrl $3,%ecx
jz 20f
18: movq (%rsi),%r8
19: movq %r8,(%rdi)
[PATCH] x86_64: Undo the earlier changes to remove unrolled copy/memset functions They cause quite bad performance regressions on Netburst This is temporary until we can get new optimized functions for these CPUs. This undoes changes that were done in 2.6.15 and in 2.6.16-rc1, essentially bringing the code back to 2.6.14 level. Only change is I renamed the X86_FEATURE_K8_C flag to X86_FEATURE_REP_GOOD and fixed the check for the flag and also fixed some comments. Signed-off-by: Andi Kleen <ak@suse.de> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-03 20:51:02 +00:00
leaq 8(%rsi),%rsi
x86: fix copy_user on x86 Switch copy_user_generic_string(), copy_user_generic_unrolled() and __copy_user_nocache() from custom tail handlers to generic copy_user_tail_handle(). Signed-off-by: Vitaly Mayatskikh <v.mayatskih@gmail.com> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-02 13:53:13 +00:00
leaq 8(%rdi),%rdi
decl %ecx
jnz 18b
20: andl %edx,%edx
jz 23f
[PATCH] x86_64: Undo the earlier changes to remove unrolled copy/memset functions They cause quite bad performance regressions on Netburst This is temporary until we can get new optimized functions for these CPUs. This undoes changes that were done in 2.6.15 and in 2.6.16-rc1, essentially bringing the code back to 2.6.14 level. Only change is I renamed the X86_FEATURE_K8_C flag to X86_FEATURE_REP_GOOD and fixed the check for the flag and also fixed some comments. Signed-off-by: Andi Kleen <ak@suse.de> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-03 20:51:02 +00:00
movl %edx,%ecx
x86: fix copy_user on x86 Switch copy_user_generic_string(), copy_user_generic_unrolled() and __copy_user_nocache() from custom tail handlers to generic copy_user_tail_handle(). Signed-off-by: Vitaly Mayatskikh <v.mayatskih@gmail.com> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-02 13:53:13 +00:00
21: movb (%rsi),%al
22: movb %al,(%rdi)
[PATCH] x86_64: Undo the earlier changes to remove unrolled copy/memset functions They cause quite bad performance regressions on Netburst This is temporary until we can get new optimized functions for these CPUs. This undoes changes that were done in 2.6.15 and in 2.6.16-rc1, essentially bringing the code back to 2.6.14 level. Only change is I renamed the X86_FEATURE_K8_C flag to X86_FEATURE_REP_GOOD and fixed the check for the flag and also fixed some comments. Signed-off-by: Andi Kleen <ak@suse.de> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-03 20:51:02 +00:00
incq %rsi
x86: fix copy_user on x86 Switch copy_user_generic_string(), copy_user_generic_unrolled() and __copy_user_nocache() from custom tail handlers to generic copy_user_tail_handle(). Signed-off-by: Vitaly Mayatskikh <v.mayatskih@gmail.com> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-02 13:53:13 +00:00
incq %rdi
[PATCH] x86_64: Undo the earlier changes to remove unrolled copy/memset functions They cause quite bad performance regressions on Netburst This is temporary until we can get new optimized functions for these CPUs. This undoes changes that were done in 2.6.15 and in 2.6.16-rc1, essentially bringing the code back to 2.6.14 level. Only change is I renamed the X86_FEATURE_K8_C flag to X86_FEATURE_REP_GOOD and fixed the check for the flag and also fixed some comments. Signed-off-by: Andi Kleen <ak@suse.de> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-03 20:51:02 +00:00
decl %ecx
x86: fix copy_user on x86 Switch copy_user_generic_string(), copy_user_generic_unrolled() and __copy_user_nocache() from custom tail handlers to generic copy_user_tail_handle(). Signed-off-by: Vitaly Mayatskikh <v.mayatskih@gmail.com> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-02 13:53:13 +00:00
jnz 21b
23: xor %eax,%eax
x86, smap: Add STAC and CLAC instructions to control user space access When Supervisor Mode Access Prevention (SMAP) is enabled, access to userspace from the kernel is controlled by the AC flag. To make the performance of manipulating that flag acceptable, there are two new instructions, STAC and CLAC, to set and clear it. This patch adds those instructions, via alternative(), when the SMAP feature is enabled. It also adds X86_EFLAGS_AC unconditionally to the SYSCALL entry mask; there is simply no reason to make that one conditional. Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Link: http://lkml.kernel.org/r/1348256595-29119-9-git-send-email-hpa@linux.intel.com
2012-09-21 19:43:12 +00:00
ASM_CLAC
[PATCH] x86_64: Undo the earlier changes to remove unrolled copy/memset functions They cause quite bad performance regressions on Netburst This is temporary until we can get new optimized functions for these CPUs. This undoes changes that were done in 2.6.15 and in 2.6.16-rc1, essentially bringing the code back to 2.6.14 level. Only change is I renamed the X86_FEATURE_K8_C flag to X86_FEATURE_REP_GOOD and fixed the check for the flag and also fixed some comments. Signed-off-by: Andi Kleen <ak@suse.de> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-03 20:51:02 +00:00
ret
x86: fix copy_user on x86 Switch copy_user_generic_string(), copy_user_generic_unrolled() and __copy_user_nocache() from custom tail handlers to generic copy_user_tail_handle(). Signed-off-by: Vitaly Mayatskikh <v.mayatskih@gmail.com> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-02 13:53:13 +00:00
.section .fixup,"ax"
30: shll $6,%ecx
addl %ecx,%edx
jmp 60f
x86-64, copy_user: Use leal to produce 32-bit results When we are using lea to produce a 32-bit result, we can use the leal form, rather than using leaq and worry about truncation elsewhere. Make the leal explicit, both to be more obvious and since that is what gcc generates and thus is less likely to trigger obscure gas bugs. Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/r/1384634221-6006-1-git-send-email-fenghua.yu@intel.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2013-11-20 20:50:51 +00:00
40: leal (%rdx,%rcx,8),%edx
x86: fix copy_user on x86 Switch copy_user_generic_string(), copy_user_generic_unrolled() and __copy_user_nocache() from custom tail handlers to generic copy_user_tail_handle(). Signed-off-by: Vitaly Mayatskikh <v.mayatskih@gmail.com> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-02 13:53:13 +00:00
jmp 60f
50: movl %ecx,%edx
60: jmp copy_user_handle_tail /* ecx is zerorest also */
.previous
[PATCH] x86_64: Undo the earlier changes to remove unrolled copy/memset functions They cause quite bad performance regressions on Netburst This is temporary until we can get new optimized functions for these CPUs. This undoes changes that were done in 2.6.15 and in 2.6.16-rc1, essentially bringing the code back to 2.6.14 level. Only change is I renamed the X86_FEATURE_K8_C flag to X86_FEATURE_REP_GOOD and fixed the check for the flag and also fixed some comments. Signed-off-by: Andi Kleen <ak@suse.de> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-03 20:51:02 +00:00
x86, extable: Remove open-coded exception table entries in arch/x86/lib/copy_user_64.S Remove open-coded exception table entries in arch/x86/lib/copy_user_64.S, and replace them with _ASM_EXTABLE() macros; this will allow us to change the format and type of the exception table entries. Signed-off-by: H. Peter Anvin <hpa@zytor.com> Cc: David Daney <david.daney@cavium.com> Link: http://lkml.kernel.org/r/CA%2B55aFyijf43qSu3N9nWHEBwaGbb7T2Oq9A=9EyR=Jtyqfq_cQ@mail.gmail.com
2012-04-20 19:19:51 +00:00
_ASM_EXTABLE(1b,30b)
_ASM_EXTABLE(2b,30b)
_ASM_EXTABLE(3b,30b)
_ASM_EXTABLE(4b,30b)
_ASM_EXTABLE(5b,30b)
_ASM_EXTABLE(6b,30b)
_ASM_EXTABLE(7b,30b)
_ASM_EXTABLE(8b,30b)
_ASM_EXTABLE(9b,30b)
_ASM_EXTABLE(10b,30b)
_ASM_EXTABLE(11b,30b)
_ASM_EXTABLE(12b,30b)
_ASM_EXTABLE(13b,30b)
_ASM_EXTABLE(14b,30b)
_ASM_EXTABLE(15b,30b)
_ASM_EXTABLE(16b,30b)
_ASM_EXTABLE(18b,40b)
_ASM_EXTABLE(19b,40b)
_ASM_EXTABLE(21b,50b)
_ASM_EXTABLE(22b,50b)
[PATCH] annotate arch/x86_64/lib/*.S Add unwind annotations to arch/x86_64/lib/*.S, and also use the macros provided by linux/linkage.h where-ever possible. Some of the alternative instructions handling needed to be adjusted so that the replacement code would also have valid unwind information. Signed-off-by: Jan Beulich <jbeulich@novell.com> Signed-off-by: Andi Kleen <ak@suse.de>
2006-09-26 08:52:32 +00:00
CFI_ENDPROC
x86: fix copy_user on x86 Switch copy_user_generic_string(), copy_user_generic_unrolled() and __copy_user_nocache() from custom tail handlers to generic copy_user_tail_handle(). Signed-off-by: Vitaly Mayatskikh <v.mayatskih@gmail.com> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-02 13:53:13 +00:00
ENDPROC(copy_user_generic_unrolled)
[PATCH] annotate arch/x86_64/lib/*.S Add unwind annotations to arch/x86_64/lib/*.S, and also use the macros provided by linux/linkage.h where-ever possible. Some of the alternative instructions handling needed to be adjusted so that the replacement code would also have valid unwind information. Signed-off-by: Jan Beulich <jbeulich@novell.com> Signed-off-by: Andi Kleen <ak@suse.de>
2006-09-26 08:52:32 +00:00
x86: fix copy_user on x86 Switch copy_user_generic_string(), copy_user_generic_unrolled() and __copy_user_nocache() from custom tail handlers to generic copy_user_tail_handle(). Signed-off-by: Vitaly Mayatskikh <v.mayatskih@gmail.com> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-02 13:53:13 +00:00
/* Some CPUs run faster using the string copy instructions.
* This is also a lot simpler. Use them when possible.
*
* Only 4GB of copy is supported. This shouldn't be a problem
* because the kernel normally only writes from/to page sized chunks
* even if user space passed a longer buffer.
* And more would be dangerous because both Intel and AMD have
* errata with rep movsq > 4GB. If someone feels the need to fix
* this please consider this.
*
* Input:
* rdi destination
* rsi source
* rdx count
*
* Output:
* eax uncopied bytes or 0 if successful.
*/
[PATCH] Fix zeroing on exception in copy_*_user - Don't zero for __copy_from_user_inatomic following i386. This will prevent spurious zeros for parallel file system writers when one does a exception - The string instruction version didn't zero the output on exception. Oops. Also I cleaned up the code a bit while I was at it and added a minor optimization to the string instruction path. Signed-off-by: Andi Kleen <ak@suse.de>
2006-09-26 08:52:39 +00:00
ENTRY(copy_user_generic_string)
[PATCH] annotate arch/x86_64/lib/*.S Add unwind annotations to arch/x86_64/lib/*.S, and also use the macros provided by linux/linkage.h where-ever possible. Some of the alternative instructions handling needed to be adjusted so that the replacement code would also have valid unwind information. Signed-off-by: Jan Beulich <jbeulich@novell.com> Signed-off-by: Andi Kleen <ak@suse.de>
2006-09-26 08:52:32 +00:00
CFI_STARTPROC
x86, smap: Add STAC and CLAC instructions to control user space access When Supervisor Mode Access Prevention (SMAP) is enabled, access to userspace from the kernel is controlled by the AC flag. To make the performance of manipulating that flag acceptable, there are two new instructions, STAC and CLAC, to set and clear it. This patch adds those instructions, via alternative(), when the SMAP feature is enabled. It also adds X86_EFLAGS_AC unconditionally to the SYSCALL entry mask; there is simply no reason to make that one conditional. Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Link: http://lkml.kernel.org/r/1348256595-29119-9-git-send-email-hpa@linux.intel.com
2012-09-21 19:43:12 +00:00
ASM_STAC
x86: fix copy_user on x86 Switch copy_user_generic_string(), copy_user_generic_unrolled() and __copy_user_nocache() from custom tail handlers to generic copy_user_tail_handle(). Signed-off-by: Vitaly Mayatskikh <v.mayatskih@gmail.com> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-02 13:53:13 +00:00
cmpl $8,%edx
jb 2f /* less than 8 bytes, go to byte copy loop */
ALIGN_DESTINATION
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 22:20:36 +00:00
movl %edx,%ecx
shrl $3,%ecx
x86: fix copy_user on x86 Switch copy_user_generic_string(), copy_user_generic_unrolled() and __copy_user_nocache() from custom tail handlers to generic copy_user_tail_handle(). Signed-off-by: Vitaly Mayatskikh <v.mayatskih@gmail.com> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-02 13:53:13 +00:00
andl $7,%edx
1: rep
[PATCH] Fix zeroing on exception in copy_*_user - Don't zero for __copy_from_user_inatomic following i386. This will prevent spurious zeros for parallel file system writers when one does a exception - The string instruction version didn't zero the output on exception. Oops. Also I cleaned up the code a bit while I was at it and added a minor optimization to the string instruction path. Signed-off-by: Andi Kleen <ak@suse.de>
2006-09-26 08:52:39 +00:00
movsq
x86: fix copy_user on x86 Switch copy_user_generic_string(), copy_user_generic_unrolled() and __copy_user_nocache() from custom tail handlers to generic copy_user_tail_handle(). Signed-off-by: Vitaly Mayatskikh <v.mayatskih@gmail.com> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-02 13:53:13 +00:00
2: movl %edx,%ecx
3: rep
movsb
x86-64, copy_user: Remove zero byte check before copy user buffer. Operation of rep movsb instruction handles zero byte copy. As pointed out by Linus, there is no need to check zero size in kernel. Removing this redundant check saves a few cycles in copy user functions. Reported-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Fenghua Yu <fenghua.yu@intel.com> Link: http://lkml.kernel.org/r/1384634221-6006-1-git-send-email-fenghua.yu@intel.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2013-11-16 20:37:01 +00:00
xorl %eax,%eax
x86, smap: Add STAC and CLAC instructions to control user space access When Supervisor Mode Access Prevention (SMAP) is enabled, access to userspace from the kernel is controlled by the AC flag. To make the performance of manipulating that flag acceptable, there are two new instructions, STAC and CLAC, to set and clear it. This patch adds those instructions, via alternative(), when the SMAP feature is enabled. It also adds X86_EFLAGS_AC unconditionally to the SYSCALL entry mask; there is simply no reason to make that one conditional. Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Link: http://lkml.kernel.org/r/1348256595-29119-9-git-send-email-hpa@linux.intel.com
2012-09-21 19:43:12 +00:00
ASM_CLAC
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 22:20:36 +00:00
ret
[PATCH] Fix zeroing on exception in copy_*_user - Don't zero for __copy_from_user_inatomic following i386. This will prevent spurious zeros for parallel file system writers when one does a exception - The string instruction version didn't zero the output on exception. Oops. Also I cleaned up the code a bit while I was at it and added a minor optimization to the string instruction path. Signed-off-by: Andi Kleen <ak@suse.de>
2006-09-26 08:52:39 +00:00
x86: fix copy_user on x86 Switch copy_user_generic_string(), copy_user_generic_unrolled() and __copy_user_nocache() from custom tail handlers to generic copy_user_tail_handle(). Signed-off-by: Vitaly Mayatskikh <v.mayatskih@gmail.com> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-02 13:53:13 +00:00
.section .fixup,"ax"
x86-64, copy_user: Use leal to produce 32-bit results When we are using lea to produce a 32-bit result, we can use the leal form, rather than using leaq and worry about truncation elsewhere. Make the leal explicit, both to be more obvious and since that is what gcc generates and thus is less likely to trigger obscure gas bugs. Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/r/1384634221-6006-1-git-send-email-fenghua.yu@intel.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2013-11-20 20:50:51 +00:00
11: leal (%rdx,%rcx,8),%ecx
x86: fix copy_user on x86 Switch copy_user_generic_string(), copy_user_generic_unrolled() and __copy_user_nocache() from custom tail handlers to generic copy_user_tail_handle(). Signed-off-by: Vitaly Mayatskikh <v.mayatskih@gmail.com> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-02 13:53:13 +00:00
12: movl %ecx,%edx /* ecx is zerorest also */
jmp copy_user_handle_tail
.previous
[PATCH] x86_64: Clean up copy_*_user - Remove optimization for old B stepping Opteron - Make the fast path for copies with a multiple of eight length faster. - Minor instruction rearrangement to hopefully avoid a pipeline stall or two. - Add comment about errata to consider. Signed-off-by: Andi Kleen <ak@suse.de> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-11 21:44:45 +00:00
x86, extable: Remove open-coded exception table entries in arch/x86/lib/copy_user_64.S Remove open-coded exception table entries in arch/x86/lib/copy_user_64.S, and replace them with _ASM_EXTABLE() macros; this will allow us to change the format and type of the exception table entries. Signed-off-by: H. Peter Anvin <hpa@zytor.com> Cc: David Daney <david.daney@cavium.com> Link: http://lkml.kernel.org/r/CA%2B55aFyijf43qSu3N9nWHEBwaGbb7T2Oq9A=9EyR=Jtyqfq_cQ@mail.gmail.com
2012-04-20 19:19:51 +00:00
_ASM_EXTABLE(1b,11b)
_ASM_EXTABLE(3b,12b)
x86: fix copy_user on x86 Switch copy_user_generic_string(), copy_user_generic_unrolled() and __copy_user_nocache() from custom tail handlers to generic copy_user_tail_handle(). Signed-off-by: Vitaly Mayatskikh <v.mayatskih@gmail.com> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-02 13:53:13 +00:00
CFI_ENDPROC
ENDPROC(copy_user_generic_string)
x86, mem: copy_user_64.S: Support copy_to/from_user by enhanced REP MOVSB/STOSB Support copy_to_user/copy_from_user() by enhanced REP MOVSB/STOSB. On processors supporting enhanced REP MOVSB/STOSB, the alternative copy_user_enhanced_fast_string function using enhanced rep movsb overrides the original function and the fast string function. Signed-off-by: Fenghua Yu <fenghua.yu@intel.com> Link: http://lkml.kernel.org/r/1305671358-14478-7-git-send-email-fenghua.yu@intel.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2011-05-17 22:29:15 +00:00
/*
* Some CPUs are adding enhanced REP MOVSB/STOSB instructions.
* It's recommended to use enhanced REP MOVSB/STOSB if it's enabled.
*
* Input:
* rdi destination
* rsi source
* rdx count
*
* Output:
* eax uncopied bytes or 0 if successful.
*/
ENTRY(copy_user_enhanced_fast_string)
CFI_STARTPROC
x86, smap: Add STAC and CLAC instructions to control user space access When Supervisor Mode Access Prevention (SMAP) is enabled, access to userspace from the kernel is controlled by the AC flag. To make the performance of manipulating that flag acceptable, there are two new instructions, STAC and CLAC, to set and clear it. This patch adds those instructions, via alternative(), when the SMAP feature is enabled. It also adds X86_EFLAGS_AC unconditionally to the SYSCALL entry mask; there is simply no reason to make that one conditional. Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Link: http://lkml.kernel.org/r/1348256595-29119-9-git-send-email-hpa@linux.intel.com
2012-09-21 19:43:12 +00:00
ASM_STAC
x86, mem: copy_user_64.S: Support copy_to/from_user by enhanced REP MOVSB/STOSB Support copy_to_user/copy_from_user() by enhanced REP MOVSB/STOSB. On processors supporting enhanced REP MOVSB/STOSB, the alternative copy_user_enhanced_fast_string function using enhanced rep movsb overrides the original function and the fast string function. Signed-off-by: Fenghua Yu <fenghua.yu@intel.com> Link: http://lkml.kernel.org/r/1305671358-14478-7-git-send-email-fenghua.yu@intel.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2011-05-17 22:29:15 +00:00
movl %edx,%ecx
1: rep
movsb
x86-64, copy_user: Remove zero byte check before copy user buffer. Operation of rep movsb instruction handles zero byte copy. As pointed out by Linus, there is no need to check zero size in kernel. Removing this redundant check saves a few cycles in copy user functions. Reported-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Fenghua Yu <fenghua.yu@intel.com> Link: http://lkml.kernel.org/r/1384634221-6006-1-git-send-email-fenghua.yu@intel.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2013-11-16 20:37:01 +00:00
xorl %eax,%eax
x86, smap: Add STAC and CLAC instructions to control user space access When Supervisor Mode Access Prevention (SMAP) is enabled, access to userspace from the kernel is controlled by the AC flag. To make the performance of manipulating that flag acceptable, there are two new instructions, STAC and CLAC, to set and clear it. This patch adds those instructions, via alternative(), when the SMAP feature is enabled. It also adds X86_EFLAGS_AC unconditionally to the SYSCALL entry mask; there is simply no reason to make that one conditional. Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Link: http://lkml.kernel.org/r/1348256595-29119-9-git-send-email-hpa@linux.intel.com
2012-09-21 19:43:12 +00:00
ASM_CLAC
x86, mem: copy_user_64.S: Support copy_to/from_user by enhanced REP MOVSB/STOSB Support copy_to_user/copy_from_user() by enhanced REP MOVSB/STOSB. On processors supporting enhanced REP MOVSB/STOSB, the alternative copy_user_enhanced_fast_string function using enhanced rep movsb overrides the original function and the fast string function. Signed-off-by: Fenghua Yu <fenghua.yu@intel.com> Link: http://lkml.kernel.org/r/1305671358-14478-7-git-send-email-fenghua.yu@intel.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2011-05-17 22:29:15 +00:00
ret
.section .fixup,"ax"
12: movl %ecx,%edx /* ecx is zerorest also */
jmp copy_user_handle_tail
.previous
x86, extable: Remove open-coded exception table entries in arch/x86/lib/copy_user_64.S Remove open-coded exception table entries in arch/x86/lib/copy_user_64.S, and replace them with _ASM_EXTABLE() macros; this will allow us to change the format and type of the exception table entries. Signed-off-by: H. Peter Anvin <hpa@zytor.com> Cc: David Daney <david.daney@cavium.com> Link: http://lkml.kernel.org/r/CA%2B55aFyijf43qSu3N9nWHEBwaGbb7T2Oq9A=9EyR=Jtyqfq_cQ@mail.gmail.com
2012-04-20 19:19:51 +00:00
_ASM_EXTABLE(1b,12b)
x86, mem: copy_user_64.S: Support copy_to/from_user by enhanced REP MOVSB/STOSB Support copy_to_user/copy_from_user() by enhanced REP MOVSB/STOSB. On processors supporting enhanced REP MOVSB/STOSB, the alternative copy_user_enhanced_fast_string function using enhanced rep movsb overrides the original function and the fast string function. Signed-off-by: Fenghua Yu <fenghua.yu@intel.com> Link: http://lkml.kernel.org/r/1305671358-14478-7-git-send-email-fenghua.yu@intel.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2011-05-17 22:29:15 +00:00
CFI_ENDPROC
ENDPROC(copy_user_enhanced_fast_string)
Reference in New Issue Copy Permalink