linux-dev - Linux kernel development work

Age	Commit message (Collapse)	Author	Files	Lines
2018-06-21	x86/unwind/orc: Detect the end of the stack	Josh Poimboeuf	1	-6/+10
	The existing UNWIND_HINT_EMPTY annotations happen to be good indicators of where entry code calls into C code for the first time. So also use them to mark the end of the stack for the ORC unwinder. Use that information to set unwind->error if the ORC unwinder doesn't unwind all the way to the end. This will be needed for enabling HAVE_RELIABLE_STACKTRACE for the ORC unwinder so we can use it with the livepatch consistency model. Thanks to Jiri Slaby for teaching the ORCs about the unwind hints. Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Jiri Slaby <jslaby@suse.cz> Acked-by: Josh Poimboeuf <jpoimboe@redhat.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: https://lkml.kernel.org/lkml/20180518064713.26440-5-jslaby@suse.cz Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-10	x86/asm: Fix UNWIND_HINT_REGS macro for older binutils	Josh Poimboeuf	1	-4/+6
	Apparently the binutils 2.20 assembler can't handle the '&&' operator in the UNWIND_HINT_REGS macro. Rearrange the macro to do without it. This fixes the following error: arch/x86/entry/entry_64.S: Assembler messages: arch/x86/entry/entry_64.S:521: Error: non-constant expression in ".if" statement arch/x86/entry/entry_64.S:521: Error: non-constant expression in ".if" statement arch/x86/entry/entry_64.S:521: Error: non-constant expression in ".if" statement arch/x86/entry/entry_64.S:521: Error: non-constant expression in ".if" statement arch/x86/entry/entry_64.S:521: Error: non-constant expression in ".if" statement arch/x86/entry/entry_64.S:521: Error: non-constant expression in ".if" statement arch/x86/entry/entry_64.S:521: Error: non-constant expression in ".if" statement arch/x86/entry/entry_64.S:521: Error: non-constant expression in ".if" statement arch/x86/entry/entry_64.S:521: Error: non-constant expression in ".if" statement Reported-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.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> Fixes: 39358a033b2e ("objtool, x86: Add facility for asm code to provide unwind hints") Link: http://lkml.kernel.org/r/e2ad97c1ae49a484644b4aaa4dd3faa4d6d969b2.1502116651.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-07-18	objtool, x86: Add facility for asm code to provide unwind hints	Josh Poimboeuf	1	-0/+103
	Some asm (and inline asm) code does special things to the stack which objtool can't understand. (Nor can GCC or GNU assembler, for that matter.) In such cases we need a facility for the code to provide annotations, so the unwinder can unwind through it. This provides such a facility, in the form of unwind hints. They're similar to the GNU assembler .cfi* directives, but they give more information, and are needed in far fewer places, because objtool can fill in the blanks by following branches and adjusting the stack pointer for pushes and pops. Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.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: Jiri Slaby <jslaby@suse.cz> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: live-patching@vger.kernel.org Link: http://lkml.kernel.org/r/0f5f3c9104fca559ff4088bece1d14ae3bca52d5.1499786555.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>