kernel/linux.git/tools/arch/x86/lib, branch v5.10.257

x86/insn: Fix PUSH instruction in x86 instruction decoder opcode map

2024-06-16T11:32:13+00:00

[ Upstream commit 59162e0c11d7257cde15f907d19fefe26da66692 ] The x86 instruction decoder is used not only for decoding kernel instructions. It is also used by perf uprobes (user space probes) and by perf tools Intel Processor Trace decoding. Consequently, it needs to support instructions executed by user space also. Opcode 0x68 PUSH instruction is currently defined as 64-bit operand size only i.e. (d64). That was based on Intel SDM Opcode Map. However that is contradicted by the Instruction Set Reference section for PUSH in the same manual. Remove 64-bit operand size only annotation from opcode 0x68 PUSH instruction. Example: $ cat pushw.s .global _start .text _start: pushw $0x1234 mov $0x1,%eax # system call number (sys_exit) int $0x80 $ as -o pushw.o pushw.s $ ld -s -o pushw pushw.o $ objdump -d pushw | tail -4 0000000000401000 <.text>: 401000: 66 68 34 12 pushw $0x1234 401004: b8 01 00 00 00 mov $0x1,%eax 401009: cd 80 int $0x80 $ perf record -e intel_pt//u ./pushw [ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 0.014 MB perf.data ] Before: $ perf script --insn-trace=disasm Warning: 1 instruction trace errors pushw 10349 [000] 10586.869237014: 401000 [unknown] (/home/ahunter/git/misc/rtit-tests/pushw) pushw $0x1234 pushw 10349 [000] 10586.869237014: 401006 [unknown] (/home/ahunter/git/misc/rtit-tests/pushw) addb %al, (%rax) pushw 10349 [000] 10586.869237014: 401008 [unknown] (/home/ahunter/git/misc/rtit-tests/pushw) addb %cl, %ch pushw 10349 [000] 10586.869237014: 40100a [unknown] (/home/ahunter/git/misc/rtit-tests/pushw) addb $0x2e, (%rax) instruction trace error type 1 time 10586.869237224 cpu 0 pid 10349 tid 10349 ip 0x40100d code 6: Trace doesn't match instruction After: $ perf script --insn-trace=disasm pushw 10349 [000] 10586.869237014: 401000 [unknown] (./pushw) pushw $0x1234 pushw 10349 [000] 10586.869237014: 401004 [unknown] (./pushw) movl $1, %eax Fixes: eb13296cfaf6 ("x86: Instruction decoder API") Signed-off-by: Adrian Hunter Signed-off-by: Ingo Molnar Link: https://lore.kernel.org/r/20240502105853.5338-3-adrian.hunter@intel.com Signed-off-by: Sasha Levin

tools arch: Update arch/x86/lib/mem{cpy,set}_64.S copies used in 'perf bench mem memcpy' - again

2022-07-25T09:26:56+00:00

commit fb24e308b6310541e70d11a3f19dc40742974b95 upstream. To bring in the change made in this cset: 5e21a3ecad1500e3 ("x86/alternative: Merge include files") This just silences these perf tools build warnings, no change in the tools: Warning: Kernel ABI header at 'tools/arch/x86/lib/memcpy_64.S' differs from latest version at 'arch/x86/lib/memcpy_64.S' diff -u tools/arch/x86/lib/memcpy_64.S arch/x86/lib/memcpy_64.S Warning: Kernel ABI header at 'tools/arch/x86/lib/memset_64.S' differs from latest version at 'arch/x86/lib/memset_64.S' diff -u tools/arch/x86/lib/memset_64.S arch/x86/lib/memset_64.S Cc: Borislav Petkov Cc: Juergen Gross Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: Greg Kroah-Hartman

tools/insn: Restore the relative include paths for cross building

2022-07-25T09:26:52+00:00

commit 0705ef64d1ff52b817e278ca6e28095585ff31e1 upstream. Building perf on ppc causes: In file included from util/intel-pt-decoder/intel-pt-insn-decoder.c:15: util/intel-pt-decoder/../../../arch/x86/lib/insn.c:14:10: fatal error: asm/inat.h: No such file or directory 14 | #include /*__ignore_sync_check__ */ | ^~~~~~~~~~~~ Restore the relative include paths so that the compiler can find the headers. Fixes: 93281c4a9657 ("x86/insn: Add an insn_decode() API") Reported-by: Ian Rogers Reported-by: Stephen Rothwell Signed-off-by: Borislav Petkov Tested-by: Ian Rogers Tested-by: Stephen Rothwell Link: https://lkml.kernel.org/r/20210317150858.02b1bbc8@canb.auug.org.au Cc: Florian Fainelli Signed-off-by: Greg Kroah-Hartman

tools arch: Update arch/x86/lib/mem{cpy,set}_64.S copies used in 'perf bench mem memcpy'

2022-07-25T09:26:31+00:00

commit 35cb8c713a496e8c114eed5e2a5a30b359876df2 upstream. To bring in the change made in this cset: f94909ceb1ed4bfd ("x86: Prepare asm files for straight-line-speculation") It silences these perf tools build warnings, no change in the tools: Warning: Kernel ABI header at 'tools/arch/x86/lib/memcpy_64.S' differs from latest version at 'arch/x86/lib/memcpy_64.S' diff -u tools/arch/x86/lib/memcpy_64.S arch/x86/lib/memcpy_64.S Warning: Kernel ABI header at 'tools/arch/x86/lib/memset_64.S' differs from latest version at 'arch/x86/lib/memset_64.S' diff -u tools/arch/x86/lib/memset_64.S arch/x86/lib/memset_64.S The code generated was checked before and after using 'objdump -d /tmp/build/perf/bench/mem-memcpy-x86-64-asm.o', no changes. Cc: Borislav Petkov Cc: Peter Zijlstra Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman Signed-off-by: Ben Hutchings Signed-off-by: Greg Kroah-Hartman

x86/insn: Add an insn_decode() API

2022-07-25T09:26:11+00:00

commit 93281c4a96572a34504244969b938e035204778d upstream. Users of the instruction decoder should use this to decode instruction bytes. For that, have insn*() helpers return an int value to denote success/failure. When there's an error fetching the next insn byte and the insn falls short, return -ENODATA to denote that. While at it, make insn_get_opcode() more stricter as to whether what has seen so far is a valid insn and if not. Copy linux/kconfig.h for the tools-version of the decoder so that it can use IS_ENABLED(). Also, cast the INSN_MODE_KERN dummy define value to (enum insn_mode) for tools use of the decoder because perf tool builds with -Werror and errors out with -Werror=sign-compare otherwise. Signed-off-by: Borislav Petkov Acked-by: Masami Hiramatsu Link: https://lkml.kernel.org/r/20210304174237.31945-5-bp@alien8.de Signed-off-by: Ben Hutchings Signed-off-by: Greg Kroah-Hartman

x86/insn: Add a __ignore_sync_check__ marker

2022-07-25T09:26:11+00:00

commit d30c7b820be5c4777fe6c3b0c21f9d0064251e51 upstream. Add an explicit __ignore_sync_check__ marker which will be used to mark lines which are supposed to be ignored by file synchronization check scripts, its advantage being that it explicitly denotes such lines in the code. Signed-off-by: Borislav Petkov Reviewed-by: Masami Hiramatsu Link: https://lkml.kernel.org/r/20210304174237.31945-4-bp@alien8.de Signed-off-by: Ben Hutchings Signed-off-by: Greg Kroah-Hartman

tools arch: Update arch/x86/lib/mem{cpy,set}_64.S copies used in 'perf bench mem memcpy'

2020-11-12T20:55:41+00:00

To bring in the change made in this cset: 4d6ffa27b8e5116c ("x86/lib: Change .weak to SYM_FUNC_START_WEAK for arch/x86/lib/mem*_64.S") 6dcc5627f6aec4cb ("x86/asm: Change all ENTRY+ENDPROC to SYM_FUNC_*") I needed to define SYM_FUNC_START_LOCAL() as SYM_L_GLOBAL as mem{cpy,set}_{orig,erms} are used by 'perf bench'. This silences these perf tools build warnings: Warning: Kernel ABI header at 'tools/arch/x86/lib/memcpy_64.S' differs from latest version at 'arch/x86/lib/memcpy_64.S' diff -u tools/arch/x86/lib/memcpy_64.S arch/x86/lib/memcpy_64.S Warning: Kernel ABI header at 'tools/arch/x86/lib/memset_64.S' differs from latest version at 'arch/x86/lib/memset_64.S' diff -u tools/arch/x86/lib/memset_64.S arch/x86/lib/memset_64.S Cc: Adrian Hunter Cc: Borislav Petkov Cc: Fangrui Song Cc: Ian Rogers Cc: Jiri Olsa Cc: Jiri Slaby Cc: Namhyung Kim Signed-off-by: Arnaldo Carvalho de Melo

x86, powerpc: Rename memcpy_mcsafe() to copy_mc_to_{user, kernel}()

2020-10-06T09:18:04+00:00

In reaction to a proposal to introduce a memcpy_mcsafe_fast() implementation Linus points out that memcpy_mcsafe() is poorly named relative to communicating the scope of the interface. Specifically what addresses are valid to pass as source, destination, and what faults / exceptions are handled. Of particular concern is that even though x86 might be able to handle the semantics of copy_mc_to_user() with its common copy_user_generic() implementation other archs likely need / want an explicit path for this case: On Fri, May 1, 2020 at 11:28 AM Linus Torvalds wrote: > > On Thu, Apr 30, 2020 at 6:21 PM Dan Williams wrote: > > > > However now I see that copy_user_generic() works for the wrong reason. > > It works because the exception on the source address due to poison > > looks no different than a write fault on the user address to the > > caller, it's still just a short copy. So it makes copy_to_user() work > > for the wrong reason relative to the name. > > Right. > > And it won't work that way on other architectures. On x86, we have a > generic function that can take faults on either side, and we use it > for both cases (and for the "in_user" case too), but that's an > artifact of the architecture oddity. > > In fact, it's probably wrong even on x86 - because it can hide bugs - > but writing those things is painful enough that everybody prefers > having just one function. Replace a single top-level memcpy_mcsafe() with either copy_mc_to_user(), or copy_mc_to_kernel(). Introduce an x86 copy_mc_fragile() name as the rename for the low-level x86 implementation formerly named memcpy_mcsafe(). It is used as the slow / careful backend that is supplanted by a fast copy_mc_generic() in a follow-on patch. One side-effect of this reorganization is that separating copy_mc_64.S to its own file means that perf no longer needs to track dependencies for its memcpy_64.S benchmarks. [ bp: Massage a bit. ] Signed-off-by: Dan Williams Signed-off-by: Borislav Petkov Reviewed-by: Tony Luck Acked-by: Michael Ellerman Cc: Link: http://lore.kernel.org/r/CAHk-=wjSqtXAqfUJxFtWNwmguFASTgB0dz1dT3V-78Quiezqbg@mail.gmail.com Link: https://lkml.kernel.org/r/160195561680.2163339.11574962055305783722.stgit@dwillia2-desk3.amr.corp.intel.com

tools arch: Update arch/x86/lib/memcpy_64.S copy used in 'perf bench mem memcpy'

2020-07-03T11:11:16+00:00

To bring in the change made in this cset: e3a9e681adb7 ("x86/entry: Fixup bad_iret vs noinstr") This doesn't cause any functional changes to tooling, just a rebuild. Addresses this perf build warning: Warning: Kernel ABI header at 'tools/arch/x86/lib/memcpy_64.S' differs from latest version at 'arch/x86/lib/memcpy_64.S' diff -u tools/arch/x86/lib/memcpy_64.S arch/x86/lib/memcpy_64.S Cc: Adrian Hunter Cc: Jiri Olsa Cc: Namhyung Kim Cc: Peter Zijlstra Signed-off-by: Arnaldo Carvalho de Melo

x86/insn: Add Control-flow Enforcement (CET) instructions to the opcode map

2020-03-26T11:21:40+00:00

Add the following CET instructions to the opcode map: INCSSP: Increment Shadow Stack pointer (SSP). RDSSP: Read SSP into a GPR. SAVEPREVSSP: Use "previous ssp" token at top of current Shadow Stack (SHSTK) to create a "restore token" on the previous (outgoing) SHSTK. RSTORSSP: Restore from a "restore token" to SSP. WRSS: Write to kernel-mode SHSTK (kernel-mode instruction). WRUSS: Write to user-mode SHSTK (kernel-mode instruction). SETSSBSY: Verify the "supervisor token" pointed by MSR_IA32_PL0_SSP, set the token busy, and set then Shadow Stack pointer(SSP) to the value of MSR_IA32_PL0_SSP. CLRSSBSY: Verify the "supervisor token" and clear its busy bit. ENDBR64/ENDBR32: Mark a valid 64/32 bit control transfer endpoint. Detailed information of CET instructions can be found in Intel Software Developer's Manual. Signed-off-by: Yu-cheng Yu Signed-off-by: Borislav Petkov Reviewed-by: Adrian Hunter Reviewed-by: Tony Luck Acked-by: Masami Hiramatsu Link: https://lkml.kernel.org/r/20200204171425.28073-2-yu-cheng.yu@intel.com