diff mbox series

[v3,10/15] parisc: Add support for suppressing warning backtraces

Message ID 20240403131936.787234-11-linux@roeck-us.net (mailing list archive)
State Not Applicable
Headers show
Series Add support for suppressing warning backtraces | expand

Checks

Context Check Description
netdev/series_format success Posting correctly formatted
netdev/tree_selection success Guessed tree name to be net-next, async
netdev/ynl success Generated files up to date; no warnings/errors; no diff in generated;
netdev/fixes_present success Fixes tag not required for -next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 8 this patch: 8
netdev/build_tools success No tools touched, skip
netdev/cc_maintainers warning 4 maintainers not CCed: palmer@dabbelt.com aou@eecs.berkeley.edu paul.walmsley@sifive.com James.Bottomley@HansenPartnership.com
netdev/build_clang success Errors and warnings before: 8 this patch: 8
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/deprecated_api success None detected
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 8 this patch: 8
netdev/checkpatch warning CHECK: spaces preferred around that '%' (ctx:BxV) WARNING: Do not crash the kernel unless it is absolutely unavoidable--use WARN_ON_ONCE() plus recovery code (if feasible) instead of BUG() or variants
netdev/build_clang_rust success No Rust files in patch. Skipping build
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0

Commit Message

Guenter Roeck April 3, 2024, 1:19 p.m. UTC 
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.

Tested-by: Linux Kernel Functional Testing <lkft@linaro.org>
Acked-by: Dan Carpenter <dan.carpenter@linaro.org>
Acked-by: Helge Deller <deller@gmx.de>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
---
v2:
- Rebased to v6.9-rc1
- Added Tested-by:, Acked-by:, and Reviewed-by: tags
- Introduced KUNIT_SUPPRESS_BACKTRACE configuration option
v3:
- Rebased to v6.9-rc2

 arch/parisc/include/asm/bug.h | 29 +++++++++++++++++++++--------
 1 file changed, 21 insertions(+), 8 deletions(-)
diff mbox series

Patch

diff --git a/arch/parisc/include/asm/bug.h b/arch/parisc/include/asm/bug.h
index 833555f74ffa..b59c3f7380bf 100644
--- a/arch/parisc/include/asm/bug.h
+++ b/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)) );		\