From 19d436268dde95389c616bb3819da73f0a8b28a8 Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Sat, 25 Feb 2017 08:56:53 +0100 Subject: debug: Add _ONCE() logic to report_bug() Josh suggested moving the _ONCE logic inside the trap handler, using a bit in the bug_entry::flags field, avoiding the need for the extra variable. Sadly this only works for WARN_ON_ONCE(), since the others have printk() statements prior to triggering the trap. Still, this saves a fair amount of text and some data: text data filename 10682460 4530992 defconfig-build/vmlinux.orig 10665111 4530096 defconfig-build/vmlinux.patched Suggested-by: Josh Poimboeuf Signed-off-by: Peter Zijlstra (Intel) Cc: Andy Lutomirski Cc: Arnd Bergmann Cc: Borislav Petkov Cc: Brian Gerst Cc: Denys Vlasenko Cc: H. Peter Anvin Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Signed-off-by: Ingo Molnar --- arch/powerpc/include/asm/bug.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'arch/powerpc') diff --git a/arch/powerpc/include/asm/bug.h b/arch/powerpc/include/asm/bug.h index 3a39283333c3..f2c562a0a427 100644 --- a/arch/powerpc/include/asm/bug.h +++ b/arch/powerpc/include/asm/bug.h @@ -85,12 +85,12 @@ } \ } while (0) -#define __WARN_TAINT(taint) do { \ +#define __WARN_FLAGS(flags) do { \ __asm__ __volatile__( \ "1: twi 31,0,0\n" \ _EMIT_BUG_ENTRY \ : : "i" (__FILE__), "i" (__LINE__), \ - "i" (BUGFLAG_TAINT(taint)), \ + "i" (BUGFLAG_WARNING|(flags)), \ "i" (sizeof(struct bug_entry))); \ } while (0) -- cgit v1.2.3 From b5effd3815ccbe3df1a015a6d67d8a24a27813d5 Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Thu, 30 Mar 2017 17:49:27 +0200 Subject: debug: Fix __bug_table[] in arch linker scripts The kbuild test robot reported this build failure on a number of architectures: > make.cross ARCH=arm > lib/lib.a(bug.o): In function `find_bug': > >> lib/bug.c:135: undefined reference to `__start___bug_table' > >> lib/bug.c:135: undefined reference to `__stop___bug_table' Caused by: 19d436268dde ("debug: Add _ONCE() logic to report_bug()") Which moved the BUG_TABLE from RO_DATA_SECTION() to RW_DATA_SECTION(), but a number of architectures don't use RW_DATA_SECTION(), so they ended up with no __bug_table[] ... Ideally all those would use RW_DATA_SECTION() in their linker scripts, but that's for another day. Signed-off-by: Peter Zijlstra Cc: Linus Torvalds Cc: Thomas Gleixner Cc: kbuild test robot Cc: kbuild-all@01.org Cc: tipbuild@zytor.com Link: http://lkml.kernel.org/r/20170330154927.o6qmgfp4bdhrajbm@hirez.programming.kicks-ass.net Signed-off-by: Ingo Molnar --- arch/powerpc/kernel/vmlinux.lds.S | 2 ++ 1 file changed, 2 insertions(+) (limited to 'arch/powerpc') diff --git a/arch/powerpc/kernel/vmlinux.lds.S b/arch/powerpc/kernel/vmlinux.lds.S index 7394b770ae1f..1c24c894c908 100644 --- a/arch/powerpc/kernel/vmlinux.lds.S +++ b/arch/powerpc/kernel/vmlinux.lds.S @@ -312,6 +312,8 @@ SECTIONS NOSAVE_DATA } + BUG_TABLE + . = ALIGN(PAGE_SIZE); _edata = .; PROVIDE32 (edata = .); -- cgit v1.2.3