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author | Linus Torvalds <torvalds@linux-foundation.org> | 2015-04-13 22:16:36 +0200 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2015-04-13 22:16:36 +0200 |
commit | 60f898eeaaa1c5d0162a4240bacf33a6c87ecef6 (patch) | |
tree | 23eeac4b1e9a616779d22c104dbc8bd45dfeefd1 /arch/x86/lib | |
parent | Merge branch 'x86-apic-for-linus' of git://git.kernel.org/pub/scm/linux/kerne... (diff) | |
parent | perf/x86/64: Report regs_user->ax too in get_regs_user() (diff) | |
download | linux-60f898eeaaa1c5d0162a4240bacf33a6c87ecef6.tar.xz linux-60f898eeaaa1c5d0162a4240bacf33a6c87ecef6.zip |
Merge branch 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 asm changes from Ingo Molnar:
"There were lots of changes in this development cycle:
- over 100 separate cleanups, restructuring changes, speedups and
fixes in the x86 system call, irq, trap and other entry code, part
of a heroic effort to deobfuscate a decade old spaghetti asm code
and its C code dependencies (Denys Vlasenko, Andy Lutomirski)
- alternatives code fixes and enhancements (Borislav Petkov)
- simplifications and cleanups to the compat code (Brian Gerst)
- signal handling fixes and new x86 testcases (Andy Lutomirski)
- various other fixes and cleanups
By their nature many of these changes are risky - we tried to test
them well on many different x86 systems (there are no known
regressions), and they are split up finely to help bisection - but
there's still a fair bit of residual risk left so caveat emptor"
* 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (148 commits)
perf/x86/64: Report regs_user->ax too in get_regs_user()
perf/x86/64: Simplify regs_user->abi setting code in get_regs_user()
perf/x86/64: Do report user_regs->cx while we are in syscall, in get_regs_user()
perf/x86/64: Do not guess user_regs->cs, ss, sp in get_regs_user()
x86/asm/entry/32: Tidy up JNZ instructions after TESTs
x86/asm/entry/64: Reduce padding in execve stubs
x86/asm/entry/64: Remove GET_THREAD_INFO() in ret_from_fork
x86/asm/entry/64: Simplify jumps in ret_from_fork
x86/asm/entry/64: Remove a redundant jump
x86/asm/entry/64: Optimize [v]fork/clone stubs
x86/asm/entry: Zero EXTRA_REGS for stub32_execve() too
x86/asm/entry/64: Move stub_x32_execvecloser() to stub_execveat()
x86/asm/entry/64: Use common code for rt_sigreturn() epilogue
x86/asm/entry/64: Add forgotten CFI annotation
x86/asm/entry/irq: Simplify interrupt dispatch table (IDT) layout
x86/asm/entry/64: Move opportunistic sysret code to syscall code path
x86, selftests: Add sigreturn selftest
x86/alternatives: Guard NOPs optimization
x86/asm/entry: Clear EXTRA_REGS for all executable formats
x86/signal: Remove pax argument from restore_sigcontext
...
Diffstat (limited to 'arch/x86/lib')
-rw-r--r-- | arch/x86/lib/atomic64_cx8_32.S | 50 | ||||
-rw-r--r-- | arch/x86/lib/checksum_32.S | 64 | ||||
-rw-r--r-- | arch/x86/lib/clear_page_64.S | 66 | ||||
-rw-r--r-- | arch/x86/lib/copy_page_64.S | 37 | ||||
-rw-r--r-- | arch/x86/lib/copy_user_64.S | 46 | ||||
-rw-r--r-- | arch/x86/lib/csum-copy_64.S | 2 | ||||
-rw-r--r-- | arch/x86/lib/insn.c | 13 | ||||
-rw-r--r-- | arch/x86/lib/memcpy_64.S | 68 | ||||
-rw-r--r-- | arch/x86/lib/memmove_64.S | 19 | ||||
-rw-r--r-- | arch/x86/lib/memset_64.S | 61 | ||||
-rw-r--r-- | arch/x86/lib/msr-reg.S | 24 | ||||
-rw-r--r-- | arch/x86/lib/rwsem.S | 44 | ||||
-rw-r--r-- | arch/x86/lib/thunk_32.S | 18 | ||||
-rw-r--r-- | arch/x86/lib/thunk_64.S | 28 | ||||
-rw-r--r-- | arch/x86/lib/x86-opcode-map.txt | 9 |
15 files changed, 223 insertions, 326 deletions
diff --git a/arch/x86/lib/atomic64_cx8_32.S b/arch/x86/lib/atomic64_cx8_32.S index f5cc9eb1d51b..082a85167a5b 100644 --- a/arch/x86/lib/atomic64_cx8_32.S +++ b/arch/x86/lib/atomic64_cx8_32.S @@ -13,16 +13,6 @@ #include <asm/alternative-asm.h> #include <asm/dwarf2.h> -.macro SAVE reg - pushl_cfi %\reg - CFI_REL_OFFSET \reg, 0 -.endm - -.macro RESTORE reg - popl_cfi %\reg - CFI_RESTORE \reg -.endm - .macro read64 reg movl %ebx, %eax movl %ecx, %edx @@ -67,10 +57,10 @@ ENDPROC(atomic64_xchg_cx8) .macro addsub_return func ins insc ENTRY(atomic64_\func\()_return_cx8) CFI_STARTPROC - SAVE ebp - SAVE ebx - SAVE esi - SAVE edi + pushl_cfi_reg ebp + pushl_cfi_reg ebx + pushl_cfi_reg esi + pushl_cfi_reg edi movl %eax, %esi movl %edx, %edi @@ -89,10 +79,10 @@ ENTRY(atomic64_\func\()_return_cx8) 10: movl %ebx, %eax movl %ecx, %edx - RESTORE edi - RESTORE esi - RESTORE ebx - RESTORE ebp + popl_cfi_reg edi + popl_cfi_reg esi + popl_cfi_reg ebx + popl_cfi_reg ebp ret CFI_ENDPROC ENDPROC(atomic64_\func\()_return_cx8) @@ -104,7 +94,7 @@ addsub_return sub sub sbb .macro incdec_return func ins insc ENTRY(atomic64_\func\()_return_cx8) CFI_STARTPROC - SAVE ebx + pushl_cfi_reg ebx read64 %esi 1: @@ -119,7 +109,7 @@ ENTRY(atomic64_\func\()_return_cx8) 10: movl %ebx, %eax movl %ecx, %edx - RESTORE ebx + popl_cfi_reg ebx ret CFI_ENDPROC ENDPROC(atomic64_\func\()_return_cx8) @@ -130,7 +120,7 @@ incdec_return dec sub sbb ENTRY(atomic64_dec_if_positive_cx8) CFI_STARTPROC - SAVE ebx + pushl_cfi_reg ebx read64 %esi 1: @@ -146,18 +136,18 @@ ENTRY(atomic64_dec_if_positive_cx8) 2: movl %ebx, %eax movl %ecx, %edx - RESTORE ebx + popl_cfi_reg ebx ret CFI_ENDPROC ENDPROC(atomic64_dec_if_positive_cx8) ENTRY(atomic64_add_unless_cx8) CFI_STARTPROC - SAVE ebp - SAVE ebx + pushl_cfi_reg ebp + pushl_cfi_reg ebx /* these just push these two parameters on the stack */ - SAVE edi - SAVE ecx + pushl_cfi_reg edi + pushl_cfi_reg ecx movl %eax, %ebp movl %edx, %edi @@ -179,8 +169,8 @@ ENTRY(atomic64_add_unless_cx8) 3: addl $8, %esp CFI_ADJUST_CFA_OFFSET -8 - RESTORE ebx - RESTORE ebp + popl_cfi_reg ebx + popl_cfi_reg ebp ret 4: cmpl %edx, 4(%esp) @@ -192,7 +182,7 @@ ENDPROC(atomic64_add_unless_cx8) ENTRY(atomic64_inc_not_zero_cx8) CFI_STARTPROC - SAVE ebx + pushl_cfi_reg ebx read64 %esi 1: @@ -209,7 +199,7 @@ ENTRY(atomic64_inc_not_zero_cx8) movl $1, %eax 3: - RESTORE ebx + popl_cfi_reg ebx ret CFI_ENDPROC ENDPROC(atomic64_inc_not_zero_cx8) diff --git a/arch/x86/lib/checksum_32.S b/arch/x86/lib/checksum_32.S index e78b8eee6615..9bc944a91274 100644 --- a/arch/x86/lib/checksum_32.S +++ b/arch/x86/lib/checksum_32.S @@ -51,10 +51,8 @@ unsigned int csum_partial(const unsigned char * buff, int len, unsigned int sum) */ ENTRY(csum_partial) CFI_STARTPROC - pushl_cfi %esi - CFI_REL_OFFSET esi, 0 - pushl_cfi %ebx - CFI_REL_OFFSET ebx, 0 + pushl_cfi_reg esi + pushl_cfi_reg ebx movl 20(%esp),%eax # Function arg: unsigned int sum movl 16(%esp),%ecx # Function arg: int len movl 12(%esp),%esi # Function arg: unsigned char *buff @@ -127,14 +125,12 @@ ENTRY(csum_partial) 6: addl %ecx,%eax adcl $0, %eax 7: - testl $1, 12(%esp) + testb $1, 12(%esp) jz 8f roll $8, %eax 8: - popl_cfi %ebx - CFI_RESTORE ebx - popl_cfi %esi - CFI_RESTORE esi + popl_cfi_reg ebx + popl_cfi_reg esi ret CFI_ENDPROC ENDPROC(csum_partial) @@ -145,10 +141,8 @@ ENDPROC(csum_partial) ENTRY(csum_partial) CFI_STARTPROC - pushl_cfi %esi - CFI_REL_OFFSET esi, 0 - pushl_cfi %ebx - CFI_REL_OFFSET ebx, 0 + pushl_cfi_reg esi + pushl_cfi_reg ebx movl 20(%esp),%eax # Function arg: unsigned int sum movl 16(%esp),%ecx # Function arg: int len movl 12(%esp),%esi # Function arg: const unsigned char *buf @@ -251,14 +245,12 @@ ENTRY(csum_partial) addl %ebx,%eax adcl $0,%eax 80: - testl $1, 12(%esp) + testb $1, 12(%esp) jz 90f roll $8, %eax 90: - popl_cfi %ebx - CFI_RESTORE ebx - popl_cfi %esi - CFI_RESTORE esi + popl_cfi_reg ebx + popl_cfi_reg esi ret CFI_ENDPROC ENDPROC(csum_partial) @@ -298,12 +290,9 @@ ENTRY(csum_partial_copy_generic) CFI_STARTPROC subl $4,%esp CFI_ADJUST_CFA_OFFSET 4 - pushl_cfi %edi - CFI_REL_OFFSET edi, 0 - pushl_cfi %esi - CFI_REL_OFFSET esi, 0 - pushl_cfi %ebx - CFI_REL_OFFSET ebx, 0 + pushl_cfi_reg edi + pushl_cfi_reg esi + pushl_cfi_reg ebx movl ARGBASE+16(%esp),%eax # sum movl ARGBASE+12(%esp),%ecx # len movl ARGBASE+4(%esp),%esi # src @@ -412,12 +401,9 @@ DST( movb %cl, (%edi) ) .previous - popl_cfi %ebx - CFI_RESTORE ebx - popl_cfi %esi - CFI_RESTORE esi - popl_cfi %edi - CFI_RESTORE edi + popl_cfi_reg ebx + popl_cfi_reg esi + popl_cfi_reg edi popl_cfi %ecx # equivalent to addl $4,%esp ret CFI_ENDPROC @@ -441,12 +427,9 @@ ENDPROC(csum_partial_copy_generic) ENTRY(csum_partial_copy_generic) CFI_STARTPROC - pushl_cfi %ebx - CFI_REL_OFFSET ebx, 0 - pushl_cfi %edi - CFI_REL_OFFSET edi, 0 - pushl_cfi %esi - CFI_REL_OFFSET esi, 0 + pushl_cfi_reg ebx + pushl_cfi_reg edi + pushl_cfi_reg esi movl ARGBASE+4(%esp),%esi #src movl ARGBASE+8(%esp),%edi #dst movl ARGBASE+12(%esp),%ecx #len @@ -506,12 +489,9 @@ DST( movb %dl, (%edi) ) jmp 7b .previous - popl_cfi %esi - CFI_RESTORE esi - popl_cfi %edi - CFI_RESTORE edi - popl_cfi %ebx - CFI_RESTORE ebx + popl_cfi_reg esi + popl_cfi_reg edi + popl_cfi_reg ebx ret CFI_ENDPROC ENDPROC(csum_partial_copy_generic) diff --git a/arch/x86/lib/clear_page_64.S b/arch/x86/lib/clear_page_64.S index f2145cfa12a6..e67e579c93bd 100644 --- a/arch/x86/lib/clear_page_64.S +++ b/arch/x86/lib/clear_page_64.S @@ -1,31 +1,35 @@ #include <linux/linkage.h> #include <asm/dwarf2.h> +#include <asm/cpufeature.h> #include <asm/alternative-asm.h> /* - * Zero a page. - * rdi page - */ -ENTRY(clear_page_c) + * Most CPUs support enhanced REP MOVSB/STOSB instructions. It is + * recommended to use this when possible and we do use them by default. + * If enhanced REP MOVSB/STOSB is not available, try to use fast string. + * Otherwise, use original. + */ + +/* + * Zero a page. + * %rdi - page + */ +ENTRY(clear_page) CFI_STARTPROC + + ALTERNATIVE_2 "jmp clear_page_orig", "", X86_FEATURE_REP_GOOD, \ + "jmp clear_page_c_e", X86_FEATURE_ERMS + movl $4096/8,%ecx xorl %eax,%eax rep stosq ret CFI_ENDPROC -ENDPROC(clear_page_c) +ENDPROC(clear_page) -ENTRY(clear_page_c_e) +ENTRY(clear_page_orig) CFI_STARTPROC - movl $4096,%ecx - xorl %eax,%eax - rep stosb - ret - CFI_ENDPROC -ENDPROC(clear_page_c_e) -ENTRY(clear_page) - CFI_STARTPROC xorl %eax,%eax movl $4096/64,%ecx .p2align 4 @@ -45,29 +49,13 @@ ENTRY(clear_page) nop ret CFI_ENDPROC -.Lclear_page_end: -ENDPROC(clear_page) - - /* - * Some CPUs support enhanced REP MOVSB/STOSB instructions. - * It is recommended to use this when possible. - * If enhanced REP MOVSB/STOSB is not available, try to use fast string. - * Otherwise, use original function. - * - */ +ENDPROC(clear_page_orig) -#include <asm/cpufeature.h> - - .section .altinstr_replacement,"ax" -1: .byte 0xeb /* jmp <disp8> */ - .byte (clear_page_c - clear_page) - (2f - 1b) /* offset */ -2: .byte 0xeb /* jmp <disp8> */ - .byte (clear_page_c_e - clear_page) - (3f - 2b) /* offset */ -3: - .previous - .section .altinstructions,"a" - altinstruction_entry clear_page,1b,X86_FEATURE_REP_GOOD,\ - .Lclear_page_end-clear_page, 2b-1b - altinstruction_entry clear_page,2b,X86_FEATURE_ERMS, \ - .Lclear_page_end-clear_page,3b-2b - .previous +ENTRY(clear_page_c_e) + CFI_STARTPROC + movl $4096,%ecx + xorl %eax,%eax + rep stosb + ret + CFI_ENDPROC +ENDPROC(clear_page_c_e) diff --git a/arch/x86/lib/copy_page_64.S b/arch/x86/lib/copy_page_64.S index 176cca67212b..8239dbcbf984 100644 --- a/arch/x86/lib/copy_page_64.S +++ b/arch/x86/lib/copy_page_64.S @@ -2,23 +2,26 @@ #include <linux/linkage.h> #include <asm/dwarf2.h> +#include <asm/cpufeature.h> #include <asm/alternative-asm.h> +/* + * Some CPUs run faster using the string copy instructions (sane microcode). + * It is also a lot simpler. Use this when possible. But, don't use streaming + * copy unless the CPU indicates X86_FEATURE_REP_GOOD. Could vary the + * prefetch distance based on SMP/UP. + */ ALIGN -copy_page_rep: +ENTRY(copy_page) CFI_STARTPROC + ALTERNATIVE "jmp copy_page_regs", "", X86_FEATURE_REP_GOOD movl $4096/8, %ecx rep movsq ret CFI_ENDPROC -ENDPROC(copy_page_rep) - -/* - * Don't use streaming copy unless the CPU indicates X86_FEATURE_REP_GOOD. - * Could vary the prefetch distance based on SMP/UP. -*/ +ENDPROC(copy_page) -ENTRY(copy_page) +ENTRY(copy_page_regs) CFI_STARTPROC subq $2*8, %rsp CFI_ADJUST_CFA_OFFSET 2*8 @@ -90,21 +93,5 @@ ENTRY(copy_page) addq $2*8, %rsp CFI_ADJUST_CFA_OFFSET -2*8 ret -.Lcopy_page_end: CFI_ENDPROC -ENDPROC(copy_page) - - /* Some CPUs run faster using the string copy instructions. - It is also a lot simpler. Use this when possible */ - -#include <asm/cpufeature.h> - - .section .altinstr_replacement,"ax" -1: .byte 0xeb /* jmp <disp8> */ - .byte (copy_page_rep - copy_page) - (2f - 1b) /* offset */ -2: - .previous - .section .altinstructions,"a" - altinstruction_entry copy_page, 1b, X86_FEATURE_REP_GOOD, \ - .Lcopy_page_end-copy_page, 2b-1b - .previous +ENDPROC(copy_page_regs) diff --git a/arch/x86/lib/copy_user_64.S b/arch/x86/lib/copy_user_64.S index dee945d55594..fa997dfaef24 100644 --- a/arch/x86/lib/copy_user_64.S +++ b/arch/x86/lib/copy_user_64.S @@ -8,9 +8,6 @@ #include <linux/linkage.h> #include <asm/dwarf2.h> - -#define FIX_ALIGNMENT 1 - #include <asm/current.h> #include <asm/asm-offsets.h> #include <asm/thread_info.h> @@ -19,33 +16,7 @@ #include <asm/asm.h> #include <asm/smap.h> -/* - * 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 -0: - .byte 0xe9 /* 32bit jump */ - .long \orig-1f /* by default jump to orig */ -1: - .section .altinstr_replacement,"ax" -2: .byte 0xe9 /* near jump with 32bit immediate */ - .long \alt1-1b /* offset */ /* or alternatively to alt1 */ -3: .byte 0xe9 /* near jump with 32bit immediate */ - .long \alt2-1b /* offset */ /* or alternatively to alt2 */ - .previous - - .section .altinstructions,"a" - altinstruction_entry 0b,2b,\feature1,5,5 - altinstruction_entry 0b,3b,\feature2,5,5 - .previous - .endm - .macro ALIGN_DESTINATION -#ifdef FIX_ALIGNMENT /* check for bad alignment of destination */ movl %edi,%ecx andl $7,%ecx @@ -67,7 +38,6 @@ _ASM_EXTABLE(100b,103b) _ASM_EXTABLE(101b,103b) -#endif .endm /* Standard copy_to_user with segment limit checking */ @@ -79,9 +49,11 @@ ENTRY(_copy_to_user) jc bad_to_user cmpq TI_addr_limit(%rax),%rcx ja bad_to_user - ALTERNATIVE_JUMP X86_FEATURE_REP_GOOD,X86_FEATURE_ERMS, \ - copy_user_generic_unrolled,copy_user_generic_string, \ - copy_user_enhanced_fast_string + ALTERNATIVE_2 "jmp copy_user_generic_unrolled", \ + "jmp copy_user_generic_string", \ + X86_FEATURE_REP_GOOD, \ + "jmp copy_user_enhanced_fast_string", \ + X86_FEATURE_ERMS CFI_ENDPROC ENDPROC(_copy_to_user) @@ -94,9 +66,11 @@ ENTRY(_copy_from_user) jc bad_from_user cmpq TI_addr_limit(%rax),%rcx ja bad_from_user - ALTERNATIVE_JUMP X86_FEATURE_REP_GOOD,X86_FEATURE_ERMS, \ - copy_user_generic_unrolled,copy_user_generic_string, \ - copy_user_enhanced_fast_string + ALTERNATIVE_2 "jmp copy_user_generic_unrolled", \ + "jmp copy_user_generic_string", \ + X86_FEATURE_REP_GOOD, \ + "jmp copy_user_enhanced_fast_string", \ + X86_FEATURE_ERMS CFI_ENDPROC ENDPROC(_copy_from_user) diff --git a/arch/x86/lib/csum-copy_64.S b/arch/x86/lib/csum-copy_64.S index 2419d5fefae3..9734182966f3 100644 --- a/arch/x86/lib/csum-copy_64.S +++ b/arch/x86/lib/csum-copy_64.S @@ -196,7 +196,7 @@ ENTRY(csum_partial_copy_generic) /* handle last odd byte */ .Lhandle_1: - testl $1, %r10d + testb $1, %r10b jz .Lende xorl %ebx, %ebx source diff --git a/arch/x86/lib/insn.c b/arch/x86/lib/insn.c index 1313ae6b478b..8f72b334aea0 100644 --- a/arch/x86/lib/insn.c +++ b/arch/x86/lib/insn.c @@ -52,6 +52,13 @@ */ void insn_init(struct insn *insn, const void *kaddr, int buf_len, int x86_64) { + /* + * Instructions longer than MAX_INSN_SIZE (15 bytes) are invalid + * even if the input buffer is long enough to hold them. + */ + if (buf_len > MAX_INSN_SIZE) + buf_len = MAX_INSN_SIZE; + memset(insn, 0, sizeof(*insn)); insn->kaddr = kaddr; insn->end_kaddr = kaddr + buf_len; @@ -164,6 +171,12 @@ found: /* VEX.W overrides opnd_size */ insn->opnd_bytes = 8; } else { + /* + * For VEX2, fake VEX3-like byte#2. + * Makes it easier to decode vex.W, vex.vvvv, + * vex.L and vex.pp. Masking with 0x7f sets vex.W == 0. + */ + insn->vex_prefix.bytes[2] = b2 & 0x7f; insn->vex_prefix.nbytes = 2; insn->next_byte += 2; } diff --git a/arch/x86/lib/memcpy_64.S b/arch/x86/lib/memcpy_64.S index 89b53c9968e7..b046664f5a1c 100644 --- a/arch/x86/lib/memcpy_64.S +++ b/arch/x86/lib/memcpy_64.S @@ -1,12 +1,20 @@ /* Copyright 2002 Andi Kleen */ #include <linux/linkage.h> - #include <asm/cpufeature.h> #include <asm/dwarf2.h> #include <asm/alternative-asm.h> /* + * We build a jump to memcpy_orig by default which gets NOPped out on + * the majority of x86 CPUs which set REP_GOOD. In addition, CPUs which + * have the enhanced REP MOVSB/STOSB feature (ERMS), change those NOPs + * to a jmp to memcpy_erms which does the REP; MOVSB mem copy. + */ + +.weak memcpy + +/* * memcpy - Copy a memory block. * * Input: @@ -17,15 +25,11 @@ * Output: * rax original destination */ +ENTRY(__memcpy) +ENTRY(memcpy) + ALTERNATIVE_2 "jmp memcpy_orig", "", X86_FEATURE_REP_GOOD, \ + "jmp memcpy_erms", X86_FEATURE_ERMS -/* - * memcpy_c() - fast string ops (REP MOVSQ) based variant. - * - * This gets patched over the unrolled variant (below) via the - * alternative instructions framework: - */ - .section .altinstr_replacement, "ax", @progbits -.Lmemcpy_c: movq %rdi, %rax movq %rdx, %rcx shrq $3, %rcx @@ -34,29 +38,21 @@ movl %edx, %ecx rep movsb ret -.Lmemcpy_e: - .previous +ENDPROC(memcpy) +ENDPROC(__memcpy) /* - * memcpy_c_e() - enhanced fast string memcpy. This is faster and simpler than - * memcpy_c. Use memcpy_c_e when possible. - * - * This gets patched over the unrolled variant (below) via the - * alternative instructions framework: + * memcpy_erms() - enhanced fast string memcpy. This is faster and + * simpler than memcpy. Use memcpy_erms when possible. */ - .section .altinstr_replacement, "ax", @progbits -.Lmemcpy_c_e: +ENTRY(memcpy_erms) movq %rdi, %rax movq %rdx, %rcx rep movsb ret -.Lmemcpy_e_e: - .previous - -.weak memcpy +ENDPROC(memcpy_erms) -ENTRY(__memcpy) -ENTRY(memcpy) +ENTRY(memcpy_orig) CFI_STARTPROC movq %rdi, %rax @@ -183,26 +179,4 @@ ENTRY(memcpy) .Lend: retq CFI_ENDPROC -ENDPROC(memcpy) -ENDPROC(__memcpy) - - /* - * Some CPUs are adding enhanced REP MOVSB/STOSB feature - * If the feature is supported, memcpy_c_e() is the first choice. - * If enhanced rep movsb copy is not available, use fast string copy - * memcpy_c() when possible. This is faster and code is simpler than - * original memcpy(). - * Otherwise, original memcpy() is used. - * In .altinstructions section, ERMS feature is placed after REG_GOOD - * feature to implement the right patch order. - * - * Replace only beginning, memcpy is used to apply alternatives, - * so it is silly to overwrite itself with nops - reboot is the - * only outcome... - */ - .section .altinstructions, "a" - altinstruction_entry __memcpy,.Lmemcpy_c,X86_FEATURE_REP_GOOD,\ - .Lmemcpy_e-.Lmemcpy_c,.Lmemcpy_e-.Lmemcpy_c - altinstruction_entry __memcpy,.Lmemcpy_c_e,X86_FEATURE_ERMS, \ - .Lmemcpy_e_e-.Lmemcpy_c_e,.Lmemcpy_e_e-.Lmemcpy_c_e - .previous +ENDPROC(memcpy_orig) diff --git a/arch/x86/lib/memmove_64.S b/arch/x86/lib/memmove_64.S index 9c4b530575da..0f8a0d0331b9 100644 --- a/arch/x86/lib/memmove_64.S +++ b/arch/x86/lib/memmove_64.S @@ -5,7 +5,6 @@ * This assembly file is re-written from memmove_64.c file. * - Copyright 2011 Fenghua Yu <fenghua.yu@intel.com> */ -#define _STRING_C #include <linux/linkage.h> #include <asm/dwarf2.h> #include <asm/cpufeature.h> @@ -44,6 +43,8 @@ ENTRY(__memmove) jg 2f .Lmemmove_begin_forward: + ALTERNATIVE "", "movq %rdx, %rcx; rep movsb; retq", X86_FEATURE_ERMS + /* * movsq instruction have many startup latency * so we handle small size by general register. @@ -207,21 +208,5 @@ ENTRY(__memmove) 13: retq CFI_ENDPROC - - .section .altinstr_replacement,"ax" -.Lmemmove_begin_forward_efs: - /* Forward moving data. */ - movq %rdx, %rcx - rep movsb - retq -.Lmemmove_end_forward_efs: - .previous - - .section .altinstructions,"a" - altinstruction_entry .Lmemmove_begin_forward, \ - .Lmemmove_begin_forward_efs,X86_FEATURE_ERMS, \ - .Lmemmove_end_forward-.Lmemmove_begin_forward, \ - .Lmemmove_end_forward_efs-.Lmemmove_begin_forward_efs - .previous ENDPROC(__memmove) ENDPROC(memmove) diff --git a/arch/x86/lib/memset_64.S b/arch/x86/lib/memset_64.S index 6f44935c6a60..93118fb23976 100644 --- a/arch/x86/lib/memset_64.S +++ b/arch/x86/lib/memset_64.S @@ -5,19 +5,30 @@ #include <asm/cpufeature.h> #include <asm/alternative-asm.h> +.weak memset + /* * ISO C memset - set a memory block to a byte value. This function uses fast * string to get better performance than the original function. The code is * simpler and shorter than the orignal function as well. - * + * * rdi destination - * rsi value (char) - * rdx count (bytes) - * + * rsi value (char) + * rdx count (bytes) + * * rax original destination - */ - .section .altinstr_replacement, "ax", @progbits -.Lmemset_c: + */ +ENTRY(memset) +ENTRY(__memset) + /* + * Some CPUs support enhanced REP MOVSB/STOSB feature. It is recommended + * to use it when possible. If not available, use fast string instructions. + * + * Otherwise, use original memset function. + */ + ALTERNATIVE_2 "jmp memset_orig", "", X86_FEATURE_REP_GOOD, \ + "jmp memset_erms", X86_FEATURE_ERMS + movq %rdi,%r9 movq %rdx,%rcx andl $7,%edx @@ -31,8 +42,8 @@ rep stosb movq %r9,%rax ret -.Lmemset_e: - .previous +ENDPROC(memset) +ENDPROC(__memset) /* * ISO C memset - set a memory block to a byte value. This function uses @@ -45,21 +56,16 @@ * * rax original destination */ - .section .altinstr_replacement, "ax", @progbits -.Lmemset_c_e: +ENTRY(memset_erms) movq %rdi,%r9 movb %sil,%al movq %rdx,%rcx rep stosb movq %r9,%rax ret -.Lmemset_e_e: - .previous - -.weak memset +ENDPROC(memset_erms) -ENTRY(memset) -ENTRY(__memset) +ENTRY(memset_orig) CFI_STARTPROC movq %rdi,%r10 @@ -134,23 +140,4 @@ ENTRY(__memset) jmp .Lafter_bad_alignment .Lfinal: CFI_ENDPROC -ENDPROC(memset) -ENDPROC(__memset) - - /* Some CPUs support enhanced REP MOVSB/STOSB feature. - * It is recommended to use this when possible. - * - * If enhanced REP MOVSB/STOSB feature is not available, use fast string - * instructions. - * - * Otherwise, use original memset function. - * - * In .altinstructions section, ERMS feature is placed after REG_GOOD - * feature to implement the right patch order. - */ - .section .altinstructions,"a" - altinstruction_entry __memset,.Lmemset_c,X86_FEATURE_REP_GOOD,\ - .Lfinal-__memset,.Lmemset_e-.Lmemset_c - altinstruction_entry __memset,.Lmemset_c_e,X86_FEATURE_ERMS, \ - .Lfinal-__memset,.Lmemset_e_e-.Lmemset_c_e - .previous +ENDPROC(memset_orig) diff --git a/arch/x86/lib/msr-reg.S b/arch/x86/lib/msr-reg.S index f6d13eefad10..3ca5218fbece 100644 --- a/arch/x86/lib/msr-reg.S +++ b/arch/x86/lib/msr-reg.S @@ -14,8 +14,8 @@ .macro op_safe_regs op ENTRY(\op\()_safe_regs) CFI_STARTPROC - pushq_cfi %rbx - pushq_cfi %rbp + pushq_cfi_reg rbx + pushq_cfi_reg rbp movq %rdi, %r10 /* Save pointer */ xorl %r11d, %r11d /* Return value */ movl (%rdi), %eax @@ -35,8 +35,8 @@ ENTRY(\op\()_safe_regs) movl %ebp, 20(%r10) movl %esi, 24(%r10) movl %edi, 28(%r10) - popq_cfi %rbp - popq_cfi %rbx + popq_cfi_reg rbp + popq_cfi_reg rbx ret 3: CFI_RESTORE_STATE @@ -53,10 +53,10 @@ ENDPROC(\op\()_safe_regs) .macro op_safe_regs op ENTRY(\op\()_safe_regs) CFI_STARTPROC - pushl_cfi %ebx - pushl_cfi %ebp - pushl_cfi %esi - pushl_cfi %edi + pushl_cfi_reg ebx + pushl_cfi_reg ebp + pushl_cfi_reg esi + pushl_cfi_reg edi pushl_cfi $0 /* Return value */ pushl_cfi %eax movl 4(%eax), %ecx @@ -80,10 +80,10 @@ ENTRY(\op\()_safe_regs) movl %esi, 24(%eax) movl %edi, 28(%eax) popl_cfi %eax - popl_cfi %edi - popl_cfi %esi - popl_cfi %ebp - popl_cfi %ebx + popl_cfi_reg edi + popl_cfi_reg esi + popl_cfi_reg ebp + popl_cfi_reg ebx ret 3: CFI_RESTORE_STATE diff --git a/arch/x86/lib/rwsem.S b/arch/x86/lib/rwsem.S index 5dff5f042468..2322abe4da3b 100644 --- a/arch/x86/lib/rwsem.S +++ b/arch/x86/lib/rwsem.S @@ -34,10 +34,10 @@ */ #define save_common_regs \ - pushl_cfi %ecx; CFI_REL_OFFSET ecx, 0 + pushl_cfi_reg ecx #define restore_common_regs \ - popl_cfi %ecx; CFI_RESTORE ecx + popl_cfi_reg ecx /* Avoid uglifying the argument copying x86-64 needs to do. */ .macro movq src, dst @@ -64,22 +64,22 @@ */ #define save_common_regs \ - pushq_cfi %rdi; CFI_REL_OFFSET rdi, 0; \ - pushq_cfi %rsi; CFI_REL_OFFSET rsi, 0; \ - pushq_cfi %rcx; CFI_REL_OFFSET rcx, 0; \ - pushq_cfi %r8; CFI_REL_OFFSET r8, 0; \ - pushq_cfi %r9; CFI_REL_OFFSET r9, 0; \ - pushq_cfi %r10; CFI_REL_OFFSET r10, 0; \ - pushq_cfi %r11; CFI_REL_OFFSET r11, 0 + pushq_cfi_reg rdi; \ + pushq_cfi_reg rsi; \ + pushq_cfi_reg rcx; \ + pushq_cfi_reg r8; \ + pushq_cfi_reg r9; \ + pushq_cfi_reg r10; \ + pushq_cfi_reg r11 #define restore_common_regs \ - popq_cfi %r11; CFI_RESTORE r11; \ - popq_cfi %r10; CFI_RESTORE r10; \ - popq_cfi %r9; CFI_RESTORE r9; \ - popq_cfi %r8; CFI_RESTORE r8; \ - popq_cfi %rcx; CFI_RESTORE rcx; \ - popq_cfi %rsi; CFI_RESTORE rsi; \ - popq_cfi %rdi; CFI_RESTORE rdi + popq_cfi_reg r11; \ + popq_cfi_reg r10; \ + popq_cfi_reg r9; \ + popq_cfi_reg r8; \ + popq_cfi_reg rcx; \ + popq_cfi_reg rsi; \ + popq_cfi_reg rdi #endif @@ -87,12 +87,10 @@ ENTRY(call_rwsem_down_read_failed) CFI_STARTPROC save_common_regs - __ASM_SIZE(push,_cfi) %__ASM_REG(dx) - CFI_REL_OFFSET __ASM_REG(dx), 0 + __ASM_SIZE(push,_cfi_reg) __ASM_REG(dx) movq %rax,%rdi call rwsem_down_read_failed - __ASM_SIZE(pop,_cfi) %__ASM_REG(dx) - CFI_RESTORE __ASM_REG(dx) + __ASM_SIZE(pop,_cfi_reg) __ASM_REG(dx) restore_common_regs ret CFI_ENDPROC @@ -124,12 +122,10 @@ ENDPROC(call_rwsem_wake) ENTRY(call_rwsem_downgrade_wake) CFI_STARTPROC save_common_regs - __ASM_SIZE(push,_cfi) %__ASM_REG(dx) - CFI_REL_OFFSET __ASM_REG(dx), 0 + __ASM_SIZE(push,_cfi_reg) __ASM_REG(dx) movq %rax,%rdi call rwsem_downgrade_wake - __ASM_SIZE(pop,_cfi) %__ASM_REG(dx) - CFI_RESTORE __ASM_REG(dx) + __ASM_SIZE(pop,_cfi_reg) __ASM_REG(dx) restore_common_regs ret CFI_ENDPROC diff --git a/arch/x86/lib/thunk_32.S b/arch/x86/lib/thunk_32.S index e28cdaf5ac2c..5eb715087b80 100644 --- a/arch/x86/lib/thunk_32.S +++ b/arch/x86/lib/thunk_32.S @@ -13,12 +13,9 @@ .globl \name \name: CFI_STARTPROC - pushl_cfi %eax - CFI_REL_OFFSET eax, 0 - pushl_cfi %ecx - CFI_REL_OFFSET ecx, 0 - pushl_cfi %edx - CFI_REL_OFFSET edx, 0 + pushl_cfi_reg eax + pushl_cfi_reg ecx + pushl_cfi_reg edx .if \put_ret_addr_in_eax /* Place EIP in the arg1 */ @@ -26,12 +23,9 @@ .endif call \func - popl_cfi %edx - CFI_RESTORE edx - popl_cfi %ecx - CFI_RESTORE ecx - popl_cfi %eax - CFI_RESTORE eax + popl_cfi_reg edx + popl_cfi_reg ecx + popl_cfi_reg eax ret CFI_ENDPROC _ASM_NOKPROBE(\name) diff --git a/arch/x86/lib/thunk_64.S b/arch/x86/lib/thunk_64.S index b30b5ebd614a..f89ba4e93025 100644 --- a/arch/x86/lib/thunk_64.S +++ b/arch/x86/lib/thunk_64.S @@ -17,9 +17,18 @@ CFI_STARTPROC /* this one pushes 9 elems, the next one would be %rIP */ - SAVE_ARGS + pushq_cfi_reg rdi + pushq_cfi_reg rsi + pushq_cfi_reg rdx + pushq_cfi_reg rcx + pushq_cfi_reg rax + pushq_cfi_reg r8 + pushq_cfi_reg r9 + pushq_cfi_reg r10 + pushq_cfi_reg r11 .if \put_ret_addr_in_rdi + /* 9*8(%rsp) is return addr on stack */ movq_cfi_restore 9*8, rdi .endif @@ -45,11 +54,22 @@ #endif #endif - /* SAVE_ARGS below is used only for the .cfi directives it contains. */ +#if defined(CONFIG_TRACE_IRQFLAGS) \ + || defined(CONFIG_DEBUG_LOCK_ALLOC) \ + || defined(CONFIG_PREEMPT) CFI_STARTPROC - SAVE_ARGS + CFI_ADJUST_CFA_OFFSET 9*8 restore: - RESTORE_ARGS + popq_cfi_reg r11 + popq_cfi_reg r10 + popq_cfi_reg r9 + popq_cfi_reg r8 + popq_cfi_reg rax + popq_cfi_reg rcx + popq_cfi_reg rdx + popq_cfi_reg rsi + popq_cfi_reg rdi ret CFI_ENDPROC _ASM_NOKPROBE(restore) +#endif diff --git a/arch/x86/lib/x86-opcode-map.txt b/arch/x86/lib/x86-opcode-map.txt index 1a2be7c6895d..816488c0b97e 100644 --- a/arch/x86/lib/x86-opcode-map.txt +++ b/arch/x86/lib/x86-opcode-map.txt @@ -273,6 +273,9 @@ dd: ESC de: ESC df: ESC # 0xe0 - 0xef +# Note: "forced64" is Intel CPU behavior: they ignore 0x66 prefix +# in 64-bit mode. AMD CPUs accept 0x66 prefix, it causes RIP truncation +# to 16 bits. In 32-bit mode, 0x66 is accepted by both Intel and AMD. e0: LOOPNE/LOOPNZ Jb (f64) e1: LOOPE/LOOPZ Jb (f64) e2: LOOP Jb (f64) @@ -281,6 +284,10 @@ e4: IN AL,Ib e5: IN eAX,Ib e6: OUT Ib,AL e7: OUT Ib,eAX +# With 0x66 prefix in 64-bit mode, for AMD CPUs immediate offset +# in "near" jumps and calls is 16-bit. For CALL, +# push of return address is 16-bit wide, RSP is decremented by 2 +# but is not truncated to 16 bits, unlike RIP. e8: CALL Jz (f64) e9: JMP-near Jz (f64) ea: JMP-far Ap (i64) @@ -456,6 +463,7 @@ AVXcode: 1 7e: movd/q Ey,Pd | vmovd/q Ey,Vy (66),(v1) | vmovq Vq,Wq (F3),(v1) 7f: movq Qq,Pq | vmovdqa Wx,Vx (66) | vmovdqu Wx,Vx (F3) # 0x0f 0x80-0x8f +# Note: "forced64" is Intel CPU behavior (see comment about CALL insn). 80: JO Jz (f64) 81: JNO Jz (f64) 82: JB/JC/JNAE Jz (f64) @@ -842,6 +850,7 @@ EndTable GrpTable: Grp5 0: INC Ev 1: DEC Ev +# Note: "forced64" is Intel CPU behavior (see comment about CALL insn). 2: CALLN Ev (f64) 3: CALLF Ep 4: JMPN Ev (f64) |