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authorPeter Zijlstra <peterz@infradead.org>2017-02-02 14:43:51 +0100
committerIngo Molnar <mingo@kernel.org>2017-03-27 10:20:28 +0200
commit9a93848fe787a53aec404e4e00d8f7f9bbdaebb4 (patch)
tree4e3b4f0b97838278a72f47a4b4ed2825610e1969 /arch/x86/kernel/dumpstack_32.c
parentx86/ftrace: Use Makefile logic instead of #ifdef for compiling ftrace_*.o (diff)
downloadlinux-9a93848fe787a53aec404e4e00d8f7f9bbdaebb4.tar.xz
linux-9a93848fe787a53aec404e4e00d8f7f9bbdaebb4.zip
x86/debug: Implement __WARN() using UD0
By using "UD0" for WARN()s we remove the function call and its possible __FILE__ and __LINE__ immediate arguments from the instruction stream. Total image size will not change much, what we win in the instruction stream we'll lose because of the __bug_table entries. Still, saves on I$ footprint and the total image size does go down a bit. text data filename 10702123 4530992 defconfig-build/vmlinux.orig 10682460 4530992 defconfig-build/vmlinux.patched (UML didn't seem to use GENERIC_BUG at all, so remove it) Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Richard Weinberger <richard.weinberger@gmail.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'arch/x86/kernel/dumpstack_32.c')
-rw-r--r--arch/x86/kernel/dumpstack_32.c12
1 files changed, 0 insertions, 12 deletions
diff --git a/arch/x86/kernel/dumpstack_32.c b/arch/x86/kernel/dumpstack_32.c
index b0b3a3df7c20..e5f0b40e66d2 100644
--- a/arch/x86/kernel/dumpstack_32.c
+++ b/arch/x86/kernel/dumpstack_32.c
@@ -162,15 +162,3 @@ void show_regs(struct pt_regs *regs)
}
pr_cont("\n");
}
-
-int is_valid_bugaddr(unsigned long ip)
-{
- unsigned short ud2;
-
- if (ip < PAGE_OFFSET)
- return 0;
- if (probe_kernel_address((unsigned short *)ip, ud2))
- return 0;
-
- return ud2 == 0x0b0f;
-}