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| author | Peter Zijlstra <peterz@infradead.org> | 2019-03-01 15:24:33 +0100 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2019-04-03 09:36:29 +0200 |
| commit | 3693ca81151eacd498675baae56abede577e8b31 (patch) | |
| tree | 3a5a28311c024636af112d9d89dcdcb723ea960b /arch/x86/include | |
| parent | 8f4faed01e3015955801c8ef066ec7fd7a8b3902 (diff) | |
| download | linux-stable-3693ca81151eacd498675baae56abede577e8b31.tar.gz linux-stable-3693ca81151eacd498675baae56abede577e8b31.tar.bz2 linux-stable-3693ca81151eacd498675baae56abede577e8b31.zip | |
x86/uaccess: Move copy_user_handle_tail() into asm
By writing the function in asm we avoid cross object code flow and
objtool no longer gets confused about a 'stray' CLAC.
Also; the asm version is actually _simpler_.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'arch/x86/include')
| -rw-r--r-- | arch/x86/include/asm/asm.h | 24 | ||||
| -rw-r--r-- | arch/x86/include/asm/uaccess_64.h | 3 |
2 files changed, 0 insertions, 27 deletions
diff --git a/arch/x86/include/asm/asm.h b/arch/x86/include/asm/asm.h index 6467757bb39f..3ff577c0b102 100644 --- a/arch/x86/include/asm/asm.h +++ b/arch/x86/include/asm/asm.h @@ -148,30 +148,6 @@ _ASM_PTR (entry); \ .popsection -.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" -103: addl %ecx,%edx /* ecx is zerorest also */ - jmp copy_user_handle_tail - .previous - - _ASM_EXTABLE_UA(100b, 103b) - _ASM_EXTABLE_UA(101b, 103b) - .endm - #else # define _EXPAND_EXTABLE_HANDLE(x) #x # define _ASM_EXTABLE_HANDLE(from, to, handler) \ diff --git a/arch/x86/include/asm/uaccess_64.h b/arch/x86/include/asm/uaccess_64.h index a9d637bc301d..5cd1caa8bc65 100644 --- a/arch/x86/include/asm/uaccess_64.h +++ b/arch/x86/include/asm/uaccess_64.h @@ -208,9 +208,6 @@ __copy_from_user_flushcache(void *dst, const void __user *src, unsigned size) } unsigned long -copy_user_handle_tail(char *to, char *from, unsigned len); - -unsigned long mcsafe_handle_tail(char *to, char *from, unsigned len); #endif /* _ASM_X86_UACCESS_64_H */ |