Thread (5 messages) 5 messages, 4 authors, 2021-02-16

Re: [PATCH mips-next] vmlinux.lds.h: catch more UBSAN symbols into .data

From: Nick Desaulniers <hidden>
Date: 2021-02-16 17:57:57
Also in: linux-arch, lkml

On Tue, Feb 16, 2021 at 12:55 AM Alexander Lobakin [off-list ref] wrote:
LKP triggered lots of LD orphan warnings [0]:
Thanks for the patch, just some questions.

With which linker?  Was there a particular config from the bot's
report that triggered this?
quoted hunk ↗ jump to hunk
mipsel-linux-ld: warning: orphan section `.data.$Lubsan_data299' from
`init/do_mounts_rd.o' being placed in section `.data.$Lubsan_data299'
mipsel-linux-ld: warning: orphan section `.data.$Lubsan_data183' from
`init/do_mounts_rd.o' being placed in section `.data.$Lubsan_data183'
mipsel-linux-ld: warning: orphan section `.data.$Lubsan_type3' from
`init/do_mounts_rd.o' being placed in section `.data.$Lubsan_type3'
mipsel-linux-ld: warning: orphan section `.data.$Lubsan_type2' from
`init/do_mounts_rd.o' being placed in section `.data.$Lubsan_type2'
mipsel-linux-ld: warning: orphan section `.data.$Lubsan_type0' from
`init/do_mounts_rd.o' being placed in section `.data.$Lubsan_type0'

[...]

Seems like "unnamed data" isn't the only type of symbols that UBSAN
instrumentation can emit.
Catch these into .data with the wildcard as well.

[0] https://lore.kernel.org/linux-mm/202102160741.k57GCNSR-lkp@intel.com (local)

Fixes: f41b233de0ae ("vmlinux.lds.h: catch UBSAN's "unnamed data" into data")
Reported-by: kernel test robot <redacted>
Signed-off-by: Alexander Lobakin <redacted>
---
 include/asm-generic/vmlinux.lds.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h
index cc659e77fcb0..83537e5ee78f 100644
--- a/include/asm-generic/vmlinux.lds.h
+++ b/include/asm-generic/vmlinux.lds.h
@@ -95,7 +95,7 @@
  */
 #ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION
 #define TEXT_MAIN .text .text.[0-9a-zA-Z_]*
-#define DATA_MAIN .data .data.[0-9a-zA-Z_]* .data..L* .data..compoundliteral* .data.$__unnamed_*
+#define DATA_MAIN .data .data.[0-9a-zA-Z_]* .data..L* .data..compoundliteral* .data.$__unnamed_* .data.$Lubsan_*
Are these sections only created when
CONFIG_LD_DEAD_CODE_DATA_ELIMINATION is selected?  (Same with
.data.$__unnamed_*)
 #define SDATA_MAIN .sdata .sdata.[0-9a-zA-Z_]*
 #define RODATA_MAIN .rodata .rodata.[0-9a-zA-Z_]* .rodata..L*
 #define BSS_MAIN .bss .bss.[0-9a-zA-Z_]* .bss..compoundliteral*
--
2.30.1

-- 
Thanks,
~Nick Desaulniers
Keyboard shortcuts
hback out one level
jnext message in thread
kprevious message in thread
ldrill in
Escclose help / fold thread tree
?toggle this help