[PATCH v4 09/14] parisc: Add support for suppressing warning backtraces
From: Alessandro Carminati <hidden>
Date: 2025-03-13 11:44:52
Also in:
dri-devel, linux-arch, linux-arm-kernel, linux-doc, linux-kselftest, linux-riscv, linux-s390, linux-sh, lkml, loongarch
Subsystem:
parisc architecture, the rest · Maintainers:
"James E.J. Bottomley", Helge Deller, Linus Torvalds
From: Guenter Roeck <linux@roeck-us.net> 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 <redacted> Acked-by: Dan Carpenter <redacted> Acked-by: Helge Deller <deller@gmx.de> Signed-off-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Alessandro Carminati <redacted> --- arch/parisc/include/asm/bug.h | 29 +++++++++++++++++++++-------- 1 file changed, 21 insertions(+), 8 deletions(-)
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)) ); \
--
2.34.1