1. 27 12月, 2019 4 次提交
  2. 17 12月, 2018 2 次提交
  3. 18 7月, 2018 2 次提交
  4. 14 7月, 2018 1 次提交
  5. 02 7月, 2018 1 次提交
    • J
      objtool: Support GCC 8 '-fnoreorder-functions' · 08b393d0
      Josh Poimboeuf 提交于
      Since the following commit:
      
        cd77849a ("objtool: Fix GCC 8 cold subfunction detection for aliased functions")
      
      ... if the kernel is built with EXTRA_CFLAGS='-fno-reorder-functions',
      objtool can get stuck in an infinite loop.
      
      That flag causes the new GCC 8 cold subfunctions to be placed in .text
      instead of .text.unlikely.  But it also has an unfortunate quirk: in the
      symbol table, the subfunction (e.g., nmi_panic.cold.7) is nested inside
      the parent (nmi_panic).
      
      That function overlap confuses objtool, and causes it to get into an
      infinite loop in next_insn_same_func().  Here's Allan's description of
      the loop:
      
        "Objtool iterates through the instructions in nmi_panic using
        next_insn_same_func. Once it reaches the end of nmi_panic at 0x534 it
        jumps to 0x528 as that's the start of nmi_panic.cold.7. However, since
        the instructions starting at 0x528 are still associated with nmi_panic
        objtool will get stuck in a loop, continually jumping back to 0x528
        after reaching 0x534."
      
      Fix it by shortening the length of the parent function so that the
      functions no longer overlap.
      Reported-and-analyzed-by: NAllan Xavier <allan.x.xavier@oracle.com>
      Signed-off-by: NJosh Poimboeuf <jpoimboe@redhat.com>
      Cc: Allan Xavier <allan.x.xavier@oracle.com>
      Cc: Andy Lutomirski <luto@kernel.org>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Brian Gerst <brgerst@gmail.com>
      Cc: Denys Vlasenko <dvlasenk@redhat.com>
      Cc: H. Peter Anvin <hpa@zytor.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Link: http://lkml.kernel.org/r/9e704c52bee651129b036be14feda317ae5606ae.1530136978.git.jpoimboe@redhat.comSigned-off-by: NIngo Molnar <mingo@kernel.org>
      08b393d0
  6. 21 6月, 2018 1 次提交
  7. 20 6月, 2018 1 次提交
  8. 06 6月, 2018 1 次提交
    • J
      objtool: Fix GCC 8 cold subfunction detection for aliased functions · cd77849a
      Josh Poimboeuf 提交于
      The kbuild test robot reported the following issue:
      
        kernel/time/posix-stubs.o: warning: objtool: sys_ni_posix_timers.cold.1()+0x0: unreachable instruction
      
      This file creates symbol aliases for the sys_ni_posix_timers() function.
      So there are multiple ELF function symbols for the same function:
      
        23: 0000000000000150     26 FUNC    GLOBAL DEFAULT        1 __x64_sys_timer_create
        24: 0000000000000150     26 FUNC    GLOBAL DEFAULT        1 sys_ni_posix_timers
        25: 0000000000000150     26 FUNC    GLOBAL DEFAULT        1 __ia32_sys_timer_create
        26: 0000000000000150     26 FUNC    GLOBAL DEFAULT        1 __x64_sys_timer_gettime
      
      Here's the corresponding cold subfunction:
      
        11: 0000000000000000     45 FUNC    LOCAL  DEFAULT        6 sys_ni_posix_timers.cold.1
      
      When analyzing overlapping functions, objtool only looks at the first
      one in the symbol list.  The rest of the functions are basically ignored
      because they point to instructions which have already been analyzed.
      
      So in this case it analyzes the __x64_sys_timer_create() function, but
      then it fails to recognize that its cold subfunction is
      sys_ni_posix_timers.cold.1(), because the names are different.
      
      Make the subfunction detection a little smarter by associating each
      subfunction with the first function which jumps to it, since that's the
      one which will be analyzed.
      
      Unfortunately we still have to leave the original subfunction detection
      code in place, thanks to GCC switch tables.  (See the comment for more
      details.)
      
      Fixes: 13810435 ("objtool: Support GCC 8's cold subfunctions")
      Reported-by: Nkbuild test robot <lkp@intel.com>
      Signed-off-by: NJosh Poimboeuf <jpoimboe@redhat.com>
      Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Link: https://lkml.kernel.org/r/d3ba52662cbc8e3a64a3b64d44b4efc5674fd9ab.1527855808.git.jpoimboe@redhat.com
      cd77849a
  9. 19 5月, 2018 1 次提交
    • J
      objtool: Detect RIP-relative switch table references, part 2 · 7dec80cc
      Josh Poimboeuf 提交于
      With the following commit:
      
        fd35c88b ("objtool: Support GCC 8 switch tables")
      
      I added a "can't find switch jump table" warning, to stop covering up
      silent failures if add_switch_table() can't find anything.
      
      That warning found yet another bug in the objtool switch table detection
      logic.  For cases 1 and 2 (as described in the comments of
      find_switch_table()), the find_symbol_containing() check doesn't adjust
      the offset for RIP-relative switch jumps.
      
      Incidentally, this bug was already fixed for case 3 with:
      
        6f5ec299 ("objtool: Detect RIP-relative switch table references")
      
      However, that commit missed the fix for cases 1 and 2.
      
      The different cases are now starting to look more and more alike.  So
      fix the bug by consolidating them into a single case, by checking the
      original dynamic jump instruction in the case 3 loop.
      
      This also simplifies the code and makes it more robust against future
      switch table detection issues -- of which I'm sure there will be many...
      
      Switch table detection has been the most fragile area of objtool, by
      far.  I long for the day when we'll have a GCC plugin for annotating
      switch tables.  Linus asked me to delay such a plugin due to the
      flakiness of the plugin infrastructure in older versions of GCC, so this
      rickety code is what we're stuck with for now.  At least the code is now
      a little simpler than it was.
      Reported-by: Nkbuild test robot <lkp@intel.com>
      Signed-off-by: NJosh Poimboeuf <jpoimboe@redhat.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Link: http://lkml.kernel.org/r/f400541613d45689086329432f3095119ffbc328.1526674218.git.jpoimboe@redhat.comSigned-off-by: NIngo Molnar <mingo@kernel.org>
      7dec80cc
  10. 15 5月, 2018 1 次提交
    • J
      objtool: Detect RIP-relative switch table references · 6f5ec299
      Josh Poimboeuf 提交于
      Typically a switch table can be found by detecting a .rodata access
      followed an indirect jump:
      
          1969:	4a 8b 0c e5 00 00 00 	mov    0x0(,%r12,8),%rcx
          1970:	00
      			196d: R_X86_64_32S	.rodata+0x438
          1971:	e9 00 00 00 00       	jmpq   1976 <dispc_runtime_suspend+0xb6a>
      			1972: R_X86_64_PC32	__x86_indirect_thunk_rcx-0x4
      
      Randy Dunlap reported a case (seen with GCC 4.8) where the .rodata
      access uses RIP-relative addressing:
      
          19bd:	48 8b 3d 00 00 00 00 	mov    0x0(%rip),%rdi        # 19c4 <dispc_runtime_suspend+0xbb8>
      			19c0: R_X86_64_PC32	.rodata+0x45c
          19c4:	e9 00 00 00 00       	jmpq   19c9 <dispc_runtime_suspend+0xbbd>
      			19c5: R_X86_64_PC32	__x86_indirect_thunk_rdi-0x4
      
      In this case the relocation addend needs to be adjusted accordingly in
      order to find the location of the switch table.
      
      The fix is for case 3 (as described in the comments), but also make the
      existing case 1 & 2 checks more precise by only adjusting the addend for
      R_X86_64_PC32 relocations.
      
      This fixes the following warnings:
      
        drivers/video/fbdev/omap2/omapfb/dss/dispc.o: warning: objtool: dispc_runtime_suspend()+0xbb8: sibling call from callable instruction with modified stack frame
        drivers/video/fbdev/omap2/omapfb/dss/dispc.o: warning: objtool: dispc_runtime_resume()+0xcc5: sibling call from callable instruction with modified stack frame
      Reported-by: NRandy Dunlap <rdunlap@infradead.org>
      Signed-off-by: NJosh Poimboeuf <jpoimboe@redhat.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Link: http://lkml.kernel.org/r/b6098294fd67afb69af8c47c9883d7a68bf0f8ea.1526305958.git.jpoimboe@redhat.comSigned-off-by: NIngo Molnar <mingo@kernel.org>
      6f5ec299
  11. 14 5月, 2018 4 次提交
    • J
      objtool: Support GCC 8 switch tables · fd35c88b
      Josh Poimboeuf 提交于
      With GCC 8, some issues were found with the objtool switch table
      detection.
      
      1) In the .rodata section, immediately after the switch table, there can
         be another object which contains a pointer to the function which had
         the switch statement.  In this case objtool wrongly considers the
         function pointer to be part of the switch table.  Fix it by:
      
         a) making sure there are no pointers to the beginning of the
            function; and
      
         b) making sure there are no gaps in the switch table.
      
         Only the former was needed, the latter adds additional protection for
         future optimizations.
      
      2) In find_switch_table(), case 1 and case 2 are missing the check to
         ensure that the .rodata switch table data is anonymous, i.e. that it
         isn't already associated with an ELF symbol.  Fix it by adding the
         same find_symbol_containing() check which is used for case 3.
      
      This fixes the following warnings with GCC 8:
      
        drivers/block/virtio_blk.o: warning: objtool: virtio_queue_rq()+0x0: stack state mismatch: cfa1=7+8 cfa2=7+72
        net/ipv6/icmp.o: warning: objtool: icmpv6_rcv()+0x0: stack state mismatch: cfa1=7+8 cfa2=7+64
        drivers/usb/core/quirks.o: warning: objtool: quirks_param_set()+0x0: stack state mismatch: cfa1=7+8 cfa2=7+48
        drivers/mtd/nand/raw/nand_hynix.o: warning: objtool: hynix_nand_decode_id()+0x0: stack state mismatch: cfa1=7+8 cfa2=7+24
        drivers/mtd/nand/raw/nand_samsung.o: warning: objtool: samsung_nand_decode_id()+0x0: stack state mismatch: cfa1=7+8 cfa2=7+32
        drivers/gpu/drm/nouveau/nvkm/subdev/top/gk104.o: warning: objtool: gk104_top_oneinit()+0x0: stack state mismatch: cfa1=7+8 cfa2=7+64
      Reported-by: NArnd Bergmann <arnd@arndb.de>
      Reported-by: Nkbuild test robot <lkp@intel.com>
      Signed-off-by: NJosh Poimboeuf <jpoimboe@redhat.com>
      Acked-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
      Cc: David Laight <David.Laight@ACULAB.COM>
      Cc: Greg KH <gregkh@linuxfoundation.org>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Randy Dunlap <rdunlap@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: damian <damian.tometzki@icloud.com>
      Link: http://lkml.kernel.org/r/20180510224849.xwi34d6tzheb5wgw@trebleSigned-off-by: NIngo Molnar <mingo@kernel.org>
      fd35c88b
    • J
      objtool: Support GCC 8's cold subfunctions · 13810435
      Josh Poimboeuf 提交于
      GCC 8 moves a lot of unlikely code out of line to "cold" subfunctions in
      .text.unlikely.  Properly detect the new subfunctions and treat them as
      extensions of the original functions.
      
      This fixes a bunch of warnings like:
      
        kernel/cgroup/cgroup.o: warning: objtool: parse_cgroup_root_flags()+0x33: sibling call from callable instruction with modified stack frame
        kernel/cgroup/cgroup.o: warning: objtool: cgroup_addrm_files()+0x290: sibling call from callable instruction with modified stack frame
        kernel/cgroup/cgroup.o: warning: objtool: cgroup_apply_control_enable()+0x25b: sibling call from callable instruction with modified stack frame
        kernel/cgroup/cgroup.o: warning: objtool: rebind_subsystems()+0x325: sibling call from callable instruction with modified stack frame
      Reported-and-tested-by: Ndamian <damian.tometzki@icloud.com>
      Reported-by: NArnd Bergmann <arnd@arndb.de>
      Signed-off-by: NJosh Poimboeuf <jpoimboe@redhat.com>
      Acked-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
      Cc: David Laight <David.Laight@ACULAB.COM>
      Cc: Greg KH <gregkh@linuxfoundation.org>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Randy Dunlap <rdunlap@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Link: http://lkml.kernel.org/r/0965e7fcfc5f31a276f0c7f298ff770c19b68706.1525923412.git.jpoimboe@redhat.comSigned-off-by: NIngo Molnar <mingo@kernel.org>
      13810435
    • J
      objtool: Fix "noreturn" detection for recursive sibling calls · 0afd0d9e
      Josh Poimboeuf 提交于
      Objtool has some crude logic for detecting static "noreturn" functions
      (aka "dead ends").  This is necessary for being able to correctly follow
      GCC code flow when such functions are called.
      
      It's remotely possible for two functions to call each other via sibling
      calls.  If they don't have RET instructions, objtool's noreturn
      detection logic goes into a recursive loop:
      
        drivers/char/ipmi/ipmi_ssif.o: warning: objtool: return_hosed_msg()+0x0: infinite recursion (objtool bug!)
        drivers/char/ipmi/ipmi_ssif.o: warning: objtool: deliver_recv_msg()+0x0: infinite recursion (objtool bug!)
      
      Instead of reporting an error in this case, consider the functions to be
      non-dead-ends.
      Reported-and-tested-by: NRandy Dunlap <rdunlap@infradead.org>
      Signed-off-by: NJosh Poimboeuf <jpoimboe@redhat.com>
      Acked-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
      Cc: Arnd Bergmann <arnd@arndb.de>
      Cc: David Laight <David.Laight@ACULAB.COM>
      Cc: Greg KH <gregkh@linuxfoundation.org>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: damian <damian.tometzki@icloud.com>
      Link: http://lkml.kernel.org/r/7cc156408c5781a1f62085d352ced1fe39fe2f91.1525923412.git.jpoimboe@redhat.comSigned-off-by: NIngo Molnar <mingo@kernel.org>
      0afd0d9e
    • I
      objtool, kprobes/x86: Sync the latest <asm/insn.h> header with... · 4fe875e4
      Ingo Molnar 提交于
      objtool, kprobes/x86: Sync the latest <asm/insn.h> header with tools/objtool/arch/x86/include/asm/insn.h
      
      The following commit:
      
        ee6a7354: kprobes/x86: Prohibit probing on exception masking instructions
      
      Modified <asm/insn.h>, adding the insn_masking_exception() function.
      
      Sync the tooling version of the header to it, to fix this warning:
      
        Warning: synced file at 'tools/objtool/arch/x86/include/asm/insn.h' differs from latest kernel version at 'arch/x86/include/asm/insn.h'
      
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Josh Poimboeuf <jpoimboe@redhat.com>
      Cc: Masami Hiramatsu <mhiramat@kernel.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Ricardo Neri <ricardo.neri-calderon@linux.intel.com>
      Cc: Francis Deslauriers <francis.deslauriers@efficios.com>
      Cc: Oleg Nesterov <oleg@redhat.com>
      Cc: Alexei Starovoitov <ast@kernel.org>
      Cc: Steven Rostedt <rostedt@goodmis.org>
      Cc: Andy Lutomirski <luto@kernel.org>
      Cc: "H . Peter Anvin" <hpa@zytor.com>
      Cc: Yonghong Song <yhs@fb.com>
      Cc: Borislav Petkov <bp@suse.de>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: "David S . Miller" <davem@davemloft.net>
      Signed-off-by: NIngo Molnar <mingo@kernel.org>
      4fe875e4
  12. 17 4月, 2018 1 次提交
  13. 10 4月, 2018 1 次提交
    • R
      Kbuild: fix # escaping in .cmd files for future Make · 9564a8cf
      Rasmus Villemoes 提交于
      I tried building using a freshly built Make (4.2.1-69-g8a731d1), but
      already the objtool build broke with
      
      orc_dump.c: In function ‘orc_dump’:
      orc_dump.c:106:2: error: ‘elf_getshnum’ is deprecated [-Werror=deprecated-declarations]
        if (elf_getshdrnum(elf, &nr_sections)) {
      
      Turns out that with that new Make, the backslash was not removed, so cpp
      didn't see a #include directive, grep found nothing, and
      -DLIBELF_USE_DEPRECATED was wrongly put in CFLAGS.
      
      Now, that new Make behaviour is documented in their NEWS file:
      
        * WARNING: Backward-incompatibility!
          Number signs (#) appearing inside a macro reference or function invocation
          no longer introduce comments and should not be escaped with backslashes:
          thus a call such as:
            foo := $(shell echo '#')
          is legal.  Previously the number sign needed to be escaped, for example:
            foo := $(shell echo '\#')
          Now this latter will resolve to "\#".  If you want to write makefiles
          portable to both versions, assign the number sign to a variable:
            C := \#
            foo := $(shell echo '$C')
          This was claimed to be fixed in 3.81, but wasn't, for some reason.
          To detect this change search for 'nocomment' in the .FEATURES variable.
      
      This also fixes up the two make-cmd instances to replace # with $(pound)
      rather than with \#. There might very well be other places that need
      similar fixup in preparation for whatever future Make release contains
      the above change, but at least this builds an x86_64 defconfig with the
      new make.
      
      Link: https://bugzilla.kernel.org/show_bug.cgi?id=197847
      Cc: Randy Dunlap <rdunlap@infradead.org>
      Signed-off-by: NRasmus Villemoes <linux@rasmusvillemoes.dk>
      Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
      9564a8cf
  14. 27 3月, 2018 1 次提交
    • J
      objtool: Add Clang support · 3c1f0583
      Josh Poimboeuf 提交于
      Since the ORC unwinder was made the default on x86_64, Clang-built
      defconfig kernels have triggered some new objtool warnings:
      
        drivers/gpu/drm/i915/i915_gpu_error.o: warning: objtool: i915_error_printf()+0x6c: return with modified stack frame
        drivers/gpu/drm/i915/intel_display.o: warning: objtool: pipe_config_err()+0xa6: return with modified stack frame
      
      The problem is that objtool has never seen clang-built binaries before.
      
      Shockingly enough, objtool is apparently able to follow the code flow
      mostly fine, except for one instruction sequence.  Instead of a LEAVE
      instruction, clang restores RSP and RBP the long way:
      
         67c:   48 89 ec                mov    %rbp,%rsp
         67f:   5d                      pop    %rbp
      
      Teach objtool about this new code sequence.
      Reported-and-test-by: NMatthias Kaehlcke <mka@chromium.org>
      Signed-off-by: NJosh Poimboeuf <jpoimboe@redhat.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Matthias Kaehlcke <mka@chromium.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Link: http://lkml.kernel.org/r/fce88ce81c356eedcae7f00ed349cfaddb3363cc.1521741586.git.jpoimboe@redhat.comSigned-off-by: NIngo Molnar <mingo@kernel.org>
      3c1f0583
  15. 07 3月, 2018 1 次提交
  16. 28 2月, 2018 1 次提交
  17. 21 2月, 2018 3 次提交
  18. 15 2月, 2018 1 次提交
  19. 09 2月, 2018 1 次提交
  20. 30 1月, 2018 3 次提交
    • J
      objtool: Warn on stripped section symbol · 830c1e3d
      Josh Poimboeuf 提交于
      With the following fix:
      
        2a0098d7 ("objtool: Fix seg fault with gold linker")
      
      ... a seg fault was avoided, but the original seg fault condition in
      objtool wasn't fixed.  Replace the seg fault with an error message.
      Suggested-by: NIngo Molnar <mingo@kernel.org>
      Signed-off-by: NJosh Poimboeuf <jpoimboe@redhat.com>
      Cc: Andy Lutomirski <luto@kernel.org>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Dave Hansen <dave.hansen@linux.intel.com>
      Cc: David Woodhouse <dwmw2@infradead.org>
      Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
      Cc: Guenter Roeck <linux@roeck-us.net>
      Cc: H. Peter Anvin <hpa@zytor.com>
      Cc: Juergen Gross <jgross@suse.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Link: http://lkml.kernel.org/r/dc4585a70d6b975c99fc51d1957ccdde7bd52f3a.1517284349.git.jpoimboe@redhat.comSigned-off-by: NIngo Molnar <mingo@kernel.org>
      830c1e3d
    • J
      objtool: Add support for alternatives at the end of a section · 17bc3391
      Josh Poimboeuf 提交于
      Now that the previous patch gave objtool the ability to read retpoline
      alternatives, it shows a new warning:
      
        arch/x86/entry/entry_64.o: warning: objtool: .entry_trampoline: don't know how to handle alternatives at end of section
      
      This is due to the JMP_NOSPEC in entry_SYSCALL_64_trampoline().
      
      Previously, objtool ignored this situation because it wasn't needed, and
      it would have required a bit of extra code.  Now that this case exists,
      add proper support for it.
      Signed-off-by: NJosh Poimboeuf <jpoimboe@redhat.com>
      Cc: Andy Lutomirski <luto@kernel.org>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Dave Hansen <dave.hansen@linux.intel.com>
      Cc: David Woodhouse <dwmw2@infradead.org>
      Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
      Cc: Guenter Roeck <linux@roeck-us.net>
      Cc: H. Peter Anvin <hpa@zytor.com>
      Cc: Juergen Gross <jgross@suse.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Link: http://lkml.kernel.org/r/2a30a3c2158af47d891a76e69bb1ef347e0443fd.1517284349.git.jpoimboe@redhat.comSigned-off-by: NIngo Molnar <mingo@kernel.org>
      17bc3391
    • J
      objtool: Improve retpoline alternative handling · a845c7cf
      Josh Poimboeuf 提交于
      Currently objtool requires all retpolines to be:
      
        a) patched in with alternatives; and
      
        b) annotated with ANNOTATE_NOSPEC_ALTERNATIVE.
      
      If you forget to do both of the above, objtool segfaults trying to
      dereference a NULL 'insn->call_dest' pointer.
      
      Avoid that situation and print a more helpful error message:
      
        quirks.o: warning: objtool: efi_delete_dummy_variable()+0x99: unsupported intra-function call
        quirks.o: warning: objtool: If this is a retpoline, please patch it in with alternatives and annotate it with ANNOTATE_NOSPEC_ALTERNATIVE.
      
      Future improvements can be made to make objtool smarter with respect to
      retpolines, but this is a good incremental improvement for now.
      Reported-and-tested-by: NGuenter Roeck <linux@roeck-us.net>
      Signed-off-by: NJosh Poimboeuf <jpoimboe@redhat.com>
      Cc: Andy Lutomirski <luto@kernel.org>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Dave Hansen <dave.hansen@linux.intel.com>
      Cc: David Woodhouse <dwmw2@infradead.org>
      Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
      Cc: H. Peter Anvin <hpa@zytor.com>
      Cc: Juergen Gross <jgross@suse.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Link: http://lkml.kernel.org/r/819e50b6d9c2e1a22e34c1a636c0b2057cc8c6e5.1517284349.git.jpoimboe@redhat.comSigned-off-by: NIngo Molnar <mingo@kernel.org>
      a845c7cf
  21. 16 1月, 2018 2 次提交
  22. 14 1月, 2018 1 次提交
  23. 12 1月, 2018 2 次提交
    • J
      objtool: Allow alternatives to be ignored · 258c7605
      Josh Poimboeuf 提交于
      Getting objtool to understand retpolines is going to be a bit of a
      challenge.  For now, take advantage of the fact that retpolines are
      patched in with alternatives.  Just read the original (sane)
      non-alternative instruction, and ignore the patched-in retpoline.
      
      This allows objtool to understand the control flow *around* the
      retpoline, even if it can't yet follow what's inside.  This means the
      ORC unwinder will fail to unwind from inside a retpoline, but will work
      fine otherwise.
      Signed-off-by: NJosh Poimboeuf <jpoimboe@redhat.com>
      Signed-off-by: NDavid Woodhouse <dwmw@amazon.co.uk>
      Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
      Cc: gnomes@lxorguk.ukuu.org.uk
      Cc: Rik van Riel <riel@redhat.com>
      Cc: Andi Kleen <ak@linux.intel.com>
      Cc: thomas.lendacky@amd.com
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Jiri Kosina <jikos@kernel.org>
      Cc: Andy Lutomirski <luto@amacapital.net>
      Cc: Dave Hansen <dave.hansen@intel.com>
      Cc: Kees Cook <keescook@google.com>
      Cc: Tim Chen <tim.c.chen@linux.intel.com>
      Cc: Greg Kroah-Hartman <gregkh@linux-foundation.org>
      Cc: Paul Turner <pjt@google.com>
      Link: https://lkml.kernel.org/r/1515707194-20531-3-git-send-email-dwmw@amazon.co.uk
      258c7605
    • J
      objtool: Detect jumps to retpoline thunks · 39b73533
      Josh Poimboeuf 提交于
      A direct jump to a retpoline thunk is really an indirect jump in
      disguise.  Change the objtool instruction type accordingly.
      
      Objtool needs to know where indirect branches are so it can detect
      switch statement jump tables.
      
      This fixes a bunch of warnings with CONFIG_RETPOLINE like:
      
        arch/x86/events/intel/uncore_nhmex.o: warning: objtool: nhmex_rbox_msr_enable_event()+0x44: sibling call from callable instruction with modified stack frame
        kernel/signal.o: warning: objtool: copy_siginfo_to_user()+0x91: sibling call from callable instruction with modified stack frame
        ...
      Signed-off-by: NJosh Poimboeuf <jpoimboe@redhat.com>
      Signed-off-by: NDavid Woodhouse <dwmw@amazon.co.uk>
      Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
      Cc: gnomes@lxorguk.ukuu.org.uk
      Cc: Rik van Riel <riel@redhat.com>
      Cc: Andi Kleen <ak@linux.intel.com>
      Cc: thomas.lendacky@amd.com
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Jiri Kosina <jikos@kernel.org>
      Cc: Andy Lutomirski <luto@amacapital.net>
      Cc: Dave Hansen <dave.hansen@intel.com>
      Cc: Kees Cook <keescook@google.com>
      Cc: Tim Chen <tim.c.chen@linux.intel.com>
      Cc: Greg Kroah-Hartman <gregkh@linux-foundation.org>
      Cc: Paul Turner <pjt@google.com>
      Link: https://lkml.kernel.org/r/1515707194-20531-2-git-send-email-dwmw@amazon.co.uk
      39b73533
  24. 31 12月, 2017 2 次提交
  25. 28 12月, 2017 1 次提交