The patch titled
Subject: parisc: add support for suppressing warning backtraces
has been added to the -mm mm-nonmm-unstable branch. Its filename is
parisc-add-support-for-suppressing-warning-backtraces.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/parisc-add-support-for-suppressing-warning-backtraces.patch
This patch will later appear in the mm-nonmm-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
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------------------------------------------------------
From: Guenter Roeck <linux@xxxxxxxxxxxx>
Subject: parisc: add support for suppressing warning backtraces
Date: Thu, 13 Mar 2025 11:43:24 +0000
Add name of functions triggering warning backtraces to the __bug_table
object section to enable support for suppressing WARNING backtraces.
To limit image size impact, the pointer to the function name is only added
to the __bug_table section if both CONFIG_KUNIT_SUPPRESS_BACKTRACE and
CONFIG_DEBUG_BUGVERBOSE are enabled. Otherwise, the __func__ assembly
parameter is replaced with a (dummy) NULL parameter to avoid an image size
increase due to unused __func__ entries (this is necessary because
__func__ is not a define but a virtual variable).
While at it, declare assembler parameters as constants where possible.
Refine .blockz instructions to calculate the necessary padding instead of
using fixed values.
Link: https://lkml.kernel.org/r/20250313114329.284104-10-acarmina@xxxxxxxxxx
Signed-off-by: Guenter Roeck <linux@xxxxxxxxxxxx>
Signed-off-by: Alessandro Carminati <acarmina@xxxxxxxxxx>
Tested-by: Linux Kernel Functional Testing <lkft@xxxxxxxxxx>
Acked-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
Acked-by: Helge Deller <deller@xxxxxx>
Cc: Albert Ou <aou@xxxxxxxxxxxxxxxxx>
Cc: Alexander Gordeev <agordeev@xxxxxxxxxxxxx>
Cc: Arnd Bergmann <arnd@xxxxxxxx>
Cc: Arthur Grillo <arthurgrillo@xxxxxxxxxx>
Cc: Borislav Petkov <bp@xxxxxxxxx>
Cc: Brendan Higgins <brendan.higgins@xxxxxxxxx>
Cc: Catalin Marinas <catalin.marinas@xxxxxxx>
Cc: Charlie Jenkins <charlie@xxxxxxxxxxxx>
Cc: Daniel Diaz <daniel.diaz@xxxxxxxxxx>
Cc: Daniel Vetter <daniel@xxxxxxxx>
Cc: Dave Airlie <airlied@xxxxxxxxx>
Cc: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>
Cc: David Gow <davidgow@xxxxxxxxxx>
Cc: Heiko Carstens <hca@xxxxxxxxxxxxx>
Cc: Huacai Chen <chenhuacai@xxxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: Jani Nikula <jani.nikula@xxxxxxxxx>
Cc: John Paul Adrian Glaubitz <glaubitz@xxxxxxxxxxxxxxxxxxx>
Cc: Kees Cook <keescook@xxxxxxxxxxxx>
Cc: Maarten Lankhorst <maarten.lankhorst@xxxxxxxxxxxxxxx>
Cc: MaÃra Canal <mcanal@xxxxxxxxxx>
Cc: Maxime Ripard <mripard@xxxxxxxxxx>
Cc: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
Cc: Naresh Kamboju <naresh.kamboju@xxxxxxxxxx>
Cc: Palmer Dabbelt <palmer@xxxxxxxxxxx>
Cc: Paul Walmsley <paul.walmsley@xxxxxxxxxx>
Cc: Rae Moar <rmoar@xxxxxxxxxx>
Cc: Rich Felker <dalias@xxxxxxxx>
Cc: Simon Horman <horms@xxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Thomas Zimemrmann <tzimmermann@xxxxxxx>
Cc: Vasily Gorbik <gor@xxxxxxxxxxxxx>
Cc: Ville Syrjala <ville.syrjala@xxxxxxxxxxxxxxx>
Cc: Will Deacon <will@xxxxxxxxxx>
Cc: Yoshinori Sato <ysato@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
arch/parisc/include/asm/bug.h | 29 +++++++++++++++++++++--------
1 file changed, 21 insertions(+), 8 deletions(-)
--- a/arch/parisc/include/asm/bug.h~parisc-add-support-for-suppressing-warning-backtraces
+++ a/arch/parisc/include/asm/bug.h
@@ -23,8 +23,17 @@
# define __BUG_REL(val) ".word " __stringify(val)
#endif
-
#ifdef CONFIG_DEBUG_BUGVERBOSE
+
+#ifdef CONFIG_KUNIT_SUPPRESS_BACKTRACE
+# define HAVE_BUG_FUNCTION
+# define __BUG_FUNC_PTR __BUG_REL(%c1)
+# define __BUG_FUNC __func__
+#else
+# define __BUG_FUNC_PTR
+# define __BUG_FUNC NULL
+#endif /* CONFIG_KUNIT_SUPPRESS_BACKTRACE */
+
#define BUG() \
do { \
asm volatile("\n" \
@@ -33,10 +42,12 @@
"\t.align 4\n" \
"2:\t" __BUG_REL(1b) "\n" \
"\t" __BUG_REL(%c0) "\n" \
- "\t.short %1, %2\n" \
- "\t.blockz %3-2*4-2*2\n" \
+ "\t" __BUG_FUNC_PTR "\n" \
+ "\t.short %c2, %c3\n" \
+ "\t.blockz %c4-(.-2b)\n" \
"\t.popsection" \
- : : "i" (__FILE__), "i" (__LINE__), \
+ : : "i" (__FILE__), "i" (__BUG_FUNC), \
+ "i" (__LINE__), \
"i" (0), "i" (sizeof(struct bug_entry)) ); \
unreachable(); \
} while(0)
@@ -58,10 +69,12 @@
"\t.align 4\n" \
"2:\t" __BUG_REL(1b) "\n" \
"\t" __BUG_REL(%c0) "\n" \
- "\t.short %1, %2\n" \
- "\t.blockz %3-2*4-2*2\n" \
+ "\t" __BUG_FUNC_PTR "\n" \
+ "\t.short %c2, %3\n" \
+ "\t.blockz %c4-(.-2b)\n" \
"\t.popsection" \
- : : "i" (__FILE__), "i" (__LINE__), \
+ : : "i" (__FILE__), "i" (__BUG_FUNC), \
+ "i" (__LINE__), \
"i" (BUGFLAG_WARNING|(flags)), \
"i" (sizeof(struct bug_entry)) ); \
} while(0)
@@ -74,7 +87,7 @@
"\t.align 4\n" \
"2:\t" __BUG_REL(1b) "\n" \
"\t.short %0\n" \
- "\t.blockz %1-4-2\n" \
+ "\t.blockz %c1-(.-2b)\n" \
"\t.popsection" \
: : "i" (BUGFLAG_WARNING|(flags)), \
"i" (sizeof(struct bug_entry)) ); \
_
Patches currently in -mm which might be from linux@xxxxxxxxxxxx are
bug-kunit-core-support-for-suppressing-warning-backtraces.patch
kunit-bug-count-suppressed-warning-backtraces.patch
kunit-add-test-cases-for-backtrace-warning-suppression.patch
kunit-add-documentation-for-warning-backtrace-suppression-api.patch
drm-suppress-intentional-warning-backtraces-in-scaling-unit-tests.patch
x86-add-support-for-suppressing-warning-backtraces.patch
arm64-add-support-for-suppressing-warning-backtraces.patch
loongarch-add-support-for-suppressing-warning-backtraces.patch
parisc-add-support-for-suppressing-warning-backtraces.patch
s390-add-support-for-suppressing-warning-backtraces.patch
sh-add-support-for-suppressing-warning-backtraces.patch
sh-move-defines-needed-for-suppressing-warning-backtraces.patch
riscv-add-support-for-suppressing-warning-backtraces.patch
powerpc-add-support-for-suppressing-warning-backtraces.patch
