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| author | Alexander Lobakin <alobakin@pm.me> | 2021-01-10 11:56:28 +0000 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2021-03-04 10:26:21 +0100 |
| commit | de9b26b5133fdfd34b15296a0b75516cbb2314bf (patch) | |
| tree | c5ea740d03208a61e24532fe4123cb1929a92986 /arch/mips | |
| parent | 1169602150d52d8eed4558917679a241af3a56a5 (diff) | |
| download | linux-stable-de9b26b5133fdfd34b15296a0b75516cbb2314bf.tar.gz linux-stable-de9b26b5133fdfd34b15296a0b75516cbb2314bf.tar.bz2 linux-stable-de9b26b5133fdfd34b15296a0b75516cbb2314bf.zip | |
MIPS: properly stop .eh_frame generation
[ Upstream commit 894ef530012fb5078466efdfb2c15d8b2f1565cd ]
Commit 866b6a89c6d1 ("MIPS: Add DWARF unwinding to assembly") added
-fno-asynchronous-unwind-tables to KBUILD_CFLAGS to prevent compiler
from emitting .eh_frame symbols.
However, as MIPS heavily uses CFI, that's not enough. Use the
approach taken for x86 (as it also uses CFI) and explicitly put CFI
symbols into the .debug_frame section (except for VDSO).
This allows us to drop .eh_frame from DISCARDS as it's no longer
being generated.
Fixes: 866b6a89c6d1 ("MIPS: Add DWARF unwinding to assembly")
Suggested-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Alexander Lobakin <alobakin@pm.me>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'arch/mips')
| -rw-r--r-- | arch/mips/include/asm/asm.h | 18 | ||||
| -rw-r--r-- | arch/mips/kernel/vmlinux.lds.S | 1 |
2 files changed, 18 insertions, 1 deletions
diff --git a/arch/mips/include/asm/asm.h b/arch/mips/include/asm/asm.h index c23527ba65d0..64bffc1f75e0 100644 --- a/arch/mips/include/asm/asm.h +++ b/arch/mips/include/asm/asm.h @@ -20,10 +20,27 @@ #include <asm/sgidefs.h> #include <asm/asm-eva.h> +#ifndef __VDSO__ +/* + * Emit CFI data in .debug_frame sections, not .eh_frame sections. + * We don't do DWARF unwinding at runtime, so only the offline DWARF + * information is useful to anyone. Note we should change this if we + * ever decide to enable DWARF unwinding at runtime. + */ +#define CFI_SECTIONS .cfi_sections .debug_frame +#else + /* + * For the vDSO, emit both runtime unwind information and debug + * symbols for the .dbg file. + */ +#define CFI_SECTIONS +#endif + /* * LEAF - declare leaf routine */ #define LEAF(symbol) \ + CFI_SECTIONS; \ .globl symbol; \ .align 2; \ .type symbol, @function; \ @@ -36,6 +53,7 @@ symbol: .frame sp, 0, ra; \ * NESTED - declare nested routine entry point */ #define NESTED(symbol, framesize, rpc) \ + CFI_SECTIONS; \ .globl symbol; \ .align 2; \ .type symbol, @function; \ diff --git a/arch/mips/kernel/vmlinux.lds.S b/arch/mips/kernel/vmlinux.lds.S index 09770a4d9784..faf98f209b3f 100644 --- a/arch/mips/kernel/vmlinux.lds.S +++ b/arch/mips/kernel/vmlinux.lds.S @@ -226,6 +226,5 @@ SECTIONS *(.options) *(.pdr) *(.reginfo) - *(.eh_frame) } } |