Searched hist:c6cfcbd8 (Results 1 – 5 of 5) sorted by relevance
/openbmc/linux/arch/x86/kernel/ |
H A D | ibt_selftest.S | c6cfcbd8 Fri Apr 07 19:16:41 CDT 2023 Josh Poimboeuf <jpoimboe@kernel.org> x86/ibt: Convert IBT selftest to asm
The following warning is reported when frame pointers and kernel IBT are enabled:
vmlinux.o: warning: objtool: ibt_selftest+0x11: sibling call from callable instruction with modified stack frame
The problem is that objtool interprets the indirect branch in ibt_selftest() as a sibling call, and GCC inserts a (partial) frame pointer prologue before it:
0000 000000000003f550 <ibt_selftest>: 0000 3f550: f3 0f 1e fa endbr64 0004 3f554: e8 00 00 00 00 call 3f559 <ibt_selftest+0x9> 3f555: R_X86_64_PLT32 __fentry__-0x4 0009 3f559: 55 push %rbp 000a 3f55a: 48 8d 05 02 00 00 00 lea 0x2(%rip),%rax # 3f563 <ibt_selftest_ip> 0011 3f561: ff e0 jmp *%rax
Note the inline asm is missing ASM_CALL_CONSTRAINT, so the 'push %rbp' happens before the indirect branch and the 'mov %rsp, %rbp' happens afterwards.
Simplify the generated code and make it easier to understand for both tools and humans by moving the selftest to proper asm.
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/99a7e16b97bda97bf0a04aa141d6241cd8a839a2.1680912949.git.jpoimboe@kernel.org
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H A D | cet.c | c6cfcbd8 Fri Apr 07 19:16:41 CDT 2023 Josh Poimboeuf <jpoimboe@kernel.org> x86/ibt: Convert IBT selftest to asm
The following warning is reported when frame pointers and kernel IBT are enabled:
vmlinux.o: warning: objtool: ibt_selftest+0x11: sibling call from callable instruction with modified stack frame
The problem is that objtool interprets the indirect branch in ibt_selftest() as a sibling call, and GCC inserts a (partial) frame pointer prologue before it:
0000 000000000003f550 <ibt_selftest>: 0000 3f550: f3 0f 1e fa endbr64 0004 3f554: e8 00 00 00 00 call 3f559 <ibt_selftest+0x9> 3f555: R_X86_64_PLT32 __fentry__-0x4 0009 3f559: 55 push %rbp 000a 3f55a: 48 8d 05 02 00 00 00 lea 0x2(%rip),%rax # 3f563 <ibt_selftest_ip> 0011 3f561: ff e0 jmp *%rax
Note the inline asm is missing ASM_CALL_CONSTRAINT, so the 'push %rbp' happens before the indirect branch and the 'mov %rsp, %rbp' happens afterwards.
Simplify the generated code and make it easier to understand for both tools and humans by moving the selftest to proper asm.
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/99a7e16b97bda97bf0a04aa141d6241cd8a839a2.1680912949.git.jpoimboe@kernel.org
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H A D | Makefile | c6cfcbd8 Fri Apr 07 19:16:41 CDT 2023 Josh Poimboeuf <jpoimboe@kernel.org> x86/ibt: Convert IBT selftest to asm
The following warning is reported when frame pointers and kernel IBT are enabled:
vmlinux.o: warning: objtool: ibt_selftest+0x11: sibling call from callable instruction with modified stack frame
The problem is that objtool interprets the indirect branch in ibt_selftest() as a sibling call, and GCC inserts a (partial) frame pointer prologue before it:
0000 000000000003f550 <ibt_selftest>: 0000 3f550: f3 0f 1e fa endbr64 0004 3f554: e8 00 00 00 00 call 3f559 <ibt_selftest+0x9> 3f555: R_X86_64_PLT32 __fentry__-0x4 0009 3f559: 55 push %rbp 000a 3f55a: 48 8d 05 02 00 00 00 lea 0x2(%rip),%rax # 3f563 <ibt_selftest_ip> 0011 3f561: ff e0 jmp *%rax
Note the inline asm is missing ASM_CALL_CONSTRAINT, so the 'push %rbp' happens before the indirect branch and the 'mov %rsp, %rbp' happens afterwards.
Simplify the generated code and make it easier to understand for both tools and humans by moving the selftest to proper asm.
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/99a7e16b97bda97bf0a04aa141d6241cd8a839a2.1680912949.git.jpoimboe@kernel.org
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/openbmc/linux/arch/x86/include/asm/ |
H A D | traps.h | c6cfcbd8 Fri Apr 07 19:16:41 CDT 2023 Josh Poimboeuf <jpoimboe@kernel.org> x86/ibt: Convert IBT selftest to asm
The following warning is reported when frame pointers and kernel IBT are enabled:
vmlinux.o: warning: objtool: ibt_selftest+0x11: sibling call from callable instruction with modified stack frame
The problem is that objtool interprets the indirect branch in ibt_selftest() as a sibling call, and GCC inserts a (partial) frame pointer prologue before it:
0000 000000000003f550 <ibt_selftest>: 0000 3f550: f3 0f 1e fa endbr64 0004 3f554: e8 00 00 00 00 call 3f559 <ibt_selftest+0x9> 3f555: R_X86_64_PLT32 __fentry__-0x4 0009 3f559: 55 push %rbp 000a 3f55a: 48 8d 05 02 00 00 00 lea 0x2(%rip),%rax # 3f563 <ibt_selftest_ip> 0011 3f561: ff e0 jmp *%rax
Note the inline asm is missing ASM_CALL_CONSTRAINT, so the 'push %rbp' happens before the indirect branch and the 'mov %rsp, %rbp' happens afterwards.
Simplify the generated code and make it easier to understand for both tools and humans by moving the selftest to proper asm.
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/99a7e16b97bda97bf0a04aa141d6241cd8a839a2.1680912949.git.jpoimboe@kernel.org
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/openbmc/linux/arch/x86/kernel/cpu/ |
H A D | common.c | c6cfcbd8 Fri Apr 07 19:16:41 CDT 2023 Josh Poimboeuf <jpoimboe@kernel.org> x86/ibt: Convert IBT selftest to asm
The following warning is reported when frame pointers and kernel IBT are enabled:
vmlinux.o: warning: objtool: ibt_selftest+0x11: sibling call from callable instruction with modified stack frame
The problem is that objtool interprets the indirect branch in ibt_selftest() as a sibling call, and GCC inserts a (partial) frame pointer prologue before it:
0000 000000000003f550 <ibt_selftest>: 0000 3f550: f3 0f 1e fa endbr64 0004 3f554: e8 00 00 00 00 call 3f559 <ibt_selftest+0x9> 3f555: R_X86_64_PLT32 __fentry__-0x4 0009 3f559: 55 push %rbp 000a 3f55a: 48 8d 05 02 00 00 00 lea 0x2(%rip),%rax # 3f563 <ibt_selftest_ip> 0011 3f561: ff e0 jmp *%rax
Note the inline asm is missing ASM_CALL_CONSTRAINT, so the 'push %rbp' happens before the indirect branch and the 'mov %rsp, %rbp' happens afterwards.
Simplify the generated code and make it easier to understand for both tools and humans by moving the selftest to proper asm.
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/99a7e16b97bda97bf0a04aa141d6241cd8a839a2.1680912949.git.jpoimboe@kernel.org
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