linux/tools/objtool, branch v5.4

KVM: x86: Check kvm_rebooting in kvm_spurious_fault()

2019-09-25T13:23:33Z

Explicitly check kvm_rebooting in kvm_spurious_fault() prior to invoking BUG(), as opposed to assuming the caller has already done so. Letting kvm_spurious_fault() be called "directly" will allow VMX to better optimize its low level assembly flows. As a happy side effect, kvm_spurious_fault() no longer needs to be marked as a dead end since it doesn't unconditionally BUG(). Acked-by: Paolo Bonzini Cc: Josh Poimboeuf Signed-off-by: Sean Christopherson Signed-off-by: Paolo Bonzini

Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2019-09-17T00:06:21Z

Pull perf updates from Ingo Molnar: "Kernel side changes: - Improved kbprobes robustness - Intel PEBS support for PT hardware tracing - Other Intel PT improvements: high order pages memory footprint reduction and various related cleanups - Misc cleanups The perf tooling side has been very busy in this cycle, with over 300 commits. This is an incomplete high-level summary of the many improvements done by over 30 developers: - Lots of updates to the following tools: 'perf c2c' 'perf config' 'perf record' 'perf report' 'perf script' 'perf test' 'perf top' 'perf trace' - Updates to libperf and libtraceevent, and a consolidation of the proliferation of x86 instruction decoder libraries. - Vendor event updates for Intel and PowerPC CPUs, - Updates to hardware tracing tooling for ARM and Intel CPUs, - ... and lots of other changes and cleanups - see the shortlog and Git log for details" * 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (322 commits) kprobes: Prohibit probing on BUG() and WARN() address perf/x86: Make more stuff static x86, perf: Fix the dependency of the x86 insn decoder selftest objtool: Ignore intentional differences for the x86 insn decoder objtool: Update sync-check.sh from perf's check-headers.sh perf build: Ignore intentional differences for the x86 insn decoder perf intel-pt: Use shared x86 insn decoder perf intel-pt: Remove inat.c from build dependency list perf: Update .gitignore file objtool: Move x86 insn decoder to a common location perf metricgroup: Support multiple events for metricgroup perf metricgroup: Scale the metric result perf pmu: Change convert_scale from static to global perf symbols: Move mem_info and branch_info out of symbol.h perf auxtrace: Uninline functions that touch perf_session perf tools: Remove needless evlist.h include directives perf tools: Remove needless evlist.h include directives perf tools: Remove needless thread_map.h include directives perf tools: Remove needless thread.h include directives perf tools: Remove needless map.h include directives ...

objtool: Clobber user CFLAGS variable

2019-09-10T06:49:52Z

If the build user has the CFLAGS variable set in their environment, objtool blindly appends to it, which can cause unexpected behavior. Clobber CFLAGS to ensure consistent objtool compilation behavior. Reported-by: Valdis Kletnieks Tested-by: Valdis Kletnieks Signed-off-by: Josh Poimboeuf Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Link: https://lkml.kernel.org/r/83a276df209962e6058fcb6c615eef9d401c21bc.1567121311.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar

objtool: Ignore intentional differences for the x86 insn decoder

2019-09-01T01:27:52Z

Since we need to build this in !x86, we need to explicitely use the x86 files, not things like asm/insn.h, so we intentionally differ from the master copy in the kernel sources, add -I diff directives to ignore just these differences when checking for drift. Acked-by: Josh Poimboeuf Link: http://lore.kernel.org/lkml/20190830193109.p7jagidsrahoa4pn@treble Acked-by: Masami Hiramatsu Cc: Adrian Hunter Cc: Jiri Olsa Cc: Namhyung Kim Cc: Peter Zijlstra (Intel) Link: https://lkml.kernel.org/n/tip-j965m9b7xtdc83em3twfkh9o@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo

objtool: Update sync-check.sh from perf's check-headers.sh

2019-09-01T01:27:52Z

To allow using the -I trick that will be needed for checking the x86 insn decoder files. Without the specific -I lines we still get the same warnings as before: $ make -C tools/objtool/ clean ; make -C tools/objtool/ make: Entering directory '/home/acme/git/perf/tools/objtool' CLEAN objtool find -name '*.o' -delete -o -name '\.*.cmd' -delete -o -name '\.*.d' -delete rm -f arch/x86/inat-tables.c fixdep LD objtool-in.o make[1]: Leaving directory '/home/acme/git/perf/tools/objtool' Warning: Kernel ABI header at 'tools/arch/x86/include/asm/inat.h' differs from latest version at 'arch/x86/include/asm/inat.h' diff -u tools/arch/x86/include/asm/inat.h arch/x86/include/asm/inat.h Warning: Kernel ABI header at 'tools/arch/x86/include/asm/insn.h' differs from latest version at 'arch/x86/include/asm/insn.h' diff -u tools/arch/x86/include/asm/insn.h arch/x86/include/asm/insn.h Warning: Kernel ABI header at 'tools/arch/x86/lib/inat.c' differs from latest version at 'arch/x86/lib/inat.c' diff -u tools/arch/x86/lib/inat.c arch/x86/lib/inat.c Warning: Kernel ABI header at 'tools/arch/x86/lib/insn.c' differs from latest version at 'arch/x86/lib/insn.c' diff -u tools/arch/x86/lib/insn.c arch/x86/lib/insn.c /home/acme/git/perf/tools/objtool LINK objtool make: Leaving directory '/home/acme/git/perf/tools/objtool' $ The next patch will add the -I lines for those files. Acked-by: Josh Poimboeuf Link: http://lore.kernel.org/lkml/20190830193109.p7jagidsrahoa4pn@treble Acked-by: Masami Hiramatsu Cc: Adrian Hunter Cc: Jiri Olsa Cc: Namhyung Kim Cc: Peter Zijlstra (Intel) Link: https://lkml.kernel.org/n/tip-vu3p38mnxlwd80rlsnjkqcf2@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo

objtool: Move x86 insn decoder to a common location

2019-09-01T01:27:52Z

The kernel tree has three identical copies of the x86 instruction decoder. Two of them are in the tools subdir. The tools subdir is supposed to be completely standalone and separate from the kernel. So having at least one copy of the kernel decoder in the tools subdir is unavoidable. However, we don't need *two* of them. Move objtool's copy of the decoder to a shared location, so that perf will also be able to use it. Signed-off-by: Josh Poimboeuf Reviewed-by: Masami Hiramatsu Acked-by: Peter Zijlstra (Intel) Cc: Adrian Hunter Cc: Jiri Olsa Cc: x86@kernel.org Link: http://lore.kernel.org/lkml/55b486b88f6bcd0c9a2a04b34f964860c8390ca8.1567118001.git.jpoimboe@redhat.com Signed-off-by: Arnaldo Carvalho de Melo

objtool: Improve UACCESS coverage

2019-07-25T06:36:39Z

A clang build reported an (obvious) double CLAC while a GCC build did not; it turns out that objtool only re-visits instructions if the first visit was with AC=0. If OTOH the first visit was with AC=1, it completely ignores any subsequent visit, even when it has AC=0. Fix this by using a visited mask instead of a boolean, and (explicitly) mark the AC state. $ ./objtool check -b --no-fp --retpoline --uaccess drivers/gpu/drm/i915/gem/i915_gem_execbuffer.o drivers/gpu/drm/i915/gem/i915_gem_execbuffer.o: warning: objtool: .altinstr_replacement+0x22: redundant UACCESS disable drivers/gpu/drm/i915/gem/i915_gem_execbuffer.o: warning: objtool: eb_copy_relocations.isra.34()+0xea: (alt) drivers/gpu/drm/i915/gem/i915_gem_execbuffer.o: warning: objtool: .altinstr_replacement+0xffffffffffffffff: (branch) drivers/gpu/drm/i915/gem/i915_gem_execbuffer.o: warning: objtool: eb_copy_relocations.isra.34()+0xd9: (alt) drivers/gpu/drm/i915/gem/i915_gem_execbuffer.o: warning: objtool: eb_copy_relocations.isra.34()+0xb2: (branch) drivers/gpu/drm/i915/gem/i915_gem_execbuffer.o: warning: objtool: eb_copy_relocations.isra.34()+0x39: (branch) drivers/gpu/drm/i915/gem/i915_gem_execbuffer.o: warning: objtool: eb_copy_relocations.isra.34()+0x0: <=== (func) Reported-by: Josh Poimboeuf Reported-by: Thomas Gleixner Reported-by: Sedat Dilek Signed-off-by: Peter Zijlstra (Intel) Signed-off-by: Josh Poimboeuf Signed-off-by: Thomas Gleixner Tested-by: Nathan Chancellor Tested-by: Nick Desaulniers Tested-by: Sedat Dilek Link: https://github.com/ClangBuiltLinux/linux/issues/617 Link: https://lkml.kernel.org/r/5359166aad2d53f3145cd442d83d0e5115e0cd17.1564007838.git.jpoimboe@redhat.com

objtool: Support conditional retpolines

2019-07-18T19:01:10Z

A Clang-built kernel is showing the following warning: arch/x86/kernel/platform-quirks.o: warning: objtool: x86_early_init_platform_quirks()+0x84: unreachable instruction That corresponds to this code: 7e: 0f 85 00 00 00 00 jne 84 80: R_X86_64_PC32 __x86_indirect_thunk_r11-0x4 84: c3 retq This is a conditional retpoline sibling call, which is now possible thanks to retpolines. Objtool hasn't seen that before. It's incorrectly interpreting the conditional jump as an unconditional dynamic jump. Reported-by: Nick Desaulniers Signed-off-by: Josh Poimboeuf Signed-off-by: Thomas Gleixner Tested-by: Nick Desaulniers Acked-by: Peter Zijlstra (Intel) Link: https://lkml.kernel.org/r/30d4c758b267ef487fb97e6ecb2f148ad007b554.1563413318.git.jpoimboe@redhat.com

objtool: Convert insn type to enum

2019-07-18T19:01:10Z

This makes it easier to add new instruction types. Also it's hopefully more robust since the compiler should warn about out-of-range enums. Signed-off-by: Josh Poimboeuf Signed-off-by: Thomas Gleixner Tested-by: Nick Desaulniers Acked-by: Peter Zijlstra (Intel) Link: https://lkml.kernel.org/r/0740e96af0d40e54cfd6a07bf09db0fbd10793cd.1563413318.git.jpoimboe@redhat.com

objtool: Fix seg fault on bad switch table entry

2019-07-18T19:01:10Z

In one rare case, Clang generated the following code: 5ca: 83 e0 21 and $0x21,%eax 5cd: b9 04 00 00 00 mov $0x4,%ecx 5d2: ff 24 c5 00 00 00 00 jmpq *0x0(,%rax,8) 5d5: R_X86_64_32S .rodata+0x38 which uses the corresponding jump table relocations: 000000000038 000200000001 R_X86_64_64 0000000000000000 .text + 834 000000000040 000200000001 R_X86_64_64 0000000000000000 .text + 5d9 000000000048 000200000001 R_X86_64_64 0000000000000000 .text + b96 000000000050 000200000001 R_X86_64_64 0000000000000000 .text + b96 000000000058 000200000001 R_X86_64_64 0000000000000000 .text + b96 000000000060 000200000001 R_X86_64_64 0000000000000000 .text + b96 000000000068 000200000001 R_X86_64_64 0000000000000000 .text + b96 000000000070 000200000001 R_X86_64_64 0000000000000000 .text + b96 000000000078 000200000001 R_X86_64_64 0000000000000000 .text + b96 000000000080 000200000001 R_X86_64_64 0000000000000000 .text + b96 000000000088 000200000001 R_X86_64_64 0000000000000000 .text + b96 000000000090 000200000001 R_X86_64_64 0000000000000000 .text + b96 000000000098 000200000001 R_X86_64_64 0000000000000000 .text + b96 0000000000a0 000200000001 R_X86_64_64 0000000000000000 .text + b96 0000000000a8 000200000001 R_X86_64_64 0000000000000000 .text + b96 0000000000b0 000200000001 R_X86_64_64 0000000000000000 .text + b96 0000000000b8 000200000001 R_X86_64_64 0000000000000000 .text + b96 0000000000c0 000200000001 R_X86_64_64 0000000000000000 .text + b96 0000000000c8 000200000001 R_X86_64_64 0000000000000000 .text + b96 0000000000d0 000200000001 R_X86_64_64 0000000000000000 .text + b96 0000000000d8 000200000001 R_X86_64_64 0000000000000000 .text + b96 0000000000e0 000200000001 R_X86_64_64 0000000000000000 .text + b96 0000000000e8 000200000001 R_X86_64_64 0000000000000000 .text + b96 0000000000f0 000200000001 R_X86_64_64 0000000000000000 .text + b96 0000000000f8 000200000001 R_X86_64_64 0000000000000000 .text + b96 000000000100 000200000001 R_X86_64_64 0000000000000000 .text + b96 000000000108 000200000001 R_X86_64_64 0000000000000000 .text + b96 000000000110 000200000001 R_X86_64_64 0000000000000000 .text + b96 000000000118 000200000001 R_X86_64_64 0000000000000000 .text + b96 000000000120 000200000001 R_X86_64_64 0000000000000000 .text + b96 000000000128 000200000001 R_X86_64_64 0000000000000000 .text + b96 000000000130 000200000001 R_X86_64_64 0000000000000000 .text + b96 000000000138 000200000001 R_X86_64_64 0000000000000000 .text + 82f 000000000140 000200000001 R_X86_64_64 0000000000000000 .text + 828 Since %eax was masked with 0x21, only the first two and the last two entries are possible. Objtool doesn't actually emulate all the code, so it isn't smart enough to know that all the middle entries aren't reachable. They point to the NOP padding area after the end of the function, so objtool seg faulted when it tried to dereference a NULL insn->func. After this fix, objtool still gives an "unreachable" error because it stops reading the jump table when it encounters the bad addresses: /home/jpoimboe/objtool-tests/adm1275.o: warning: objtool: adm1275_probe()+0x828: unreachable instruction While the above code is technically correct, it's very wasteful of memory -- it uses 34 jump table entries when only 4 are needed. It's also not possible for objtool to validate this type of switch table because the unused entries point outside the function and objtool has no way of determining if that's intentional. Hopefully the Clang folks can fix it. Reported-by: Arnd Bergmann Signed-off-by: Josh Poimboeuf Signed-off-by: Thomas Gleixner Tested-by: Nick Desaulniers Acked-by: Peter Zijlstra (Intel) Link: https://lkml.kernel.org/r/a9db88eec4f1ca089e040989846961748238b6d8.1563413318.git.jpoimboe@redhat.com