compiler.h: Raise minimum version of GCC to 5.1 for arm64
commit dca5244d2f5b94f1809f0c02a549edf41ccd5493 upstream.
GCC versions >= 4.9 and < 5.1 have been shown to emit memory references beyond the stack pointer, resulting in memory corruption if an interrupt is taken after the stack pointer has been adjusted but before the reference has been executed. This leads to subtle, infrequent data corruption such as the EXT4 problems reported by Russell King at the link below.
Life is too short for buggy compilers, so raise the minimum GCC version required by arm64 to 5.1.
--- include/linux/compiler-gcc.h | 6 ++++++ 1 file changed, 6 insertions(+)
include/linux/compiler-gcc.h +6 -0
@@ -145,6 +145,12 @@#if GCC_VERSION <30200 # error Sorry, your compiler is too old - please upgrade it. +#elif defined(CONFIG_ARM64 ) &&GCC_VERSION <50100 +/* +* https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63293 +* https://lore.kernel.org/r/[email protected] +*/ +# error Sorry, your version of GCC is too old - please use 5.1 or newer.#endif #if GCC_VERSION <30300
Signature · 1 line
2.30.0.284.gd98b1dd5eaa7-goog
Quoted 13 lines · Will Deacon
commit
dca5244d2f5b94f1809f0c02a549edf41ccd5493upstream.GCC versions >= 4.9 and < 5.1 have been shown to emit memory references beyond the stack pointer, resulting in memory corruption if an interrupt is taken after the stack pointer has been adjusted but before the reference has been executed. This leads to subtle, infrequent data corruption such as the EXT4 problems reported by Russell King at the link below.
Life is too short for buggy compilers, so raise the minimum GCC version required by arm64 to 5.1.
Quoted 16 lines
Reported-by Russell King <[email protected]>Suggested-by Arnd Bergmann <[email protected]>Signed-off-by Will Deacon <[email protected]>Tested-by Nathan Chancellor <[email protected]>Reviewed-by Nick Desaulniers <[email protected]>Reviewed-by Nathan Chancellor <[email protected]>Acked-by Linus Torvalds <[email protected]>Cc <[email protected]> # 4.4.y, 4.9.y and 4.14.y onlyCc Theodore Ts'o <[email protected]>Cc Florian Weimer <[email protected]>Cc Peter Zijlstra <[email protected]>Cc Nick Desaulniers <[email protected]>Signed-off-by Catalin Marinas <[email protected]>[will: backport to 4.4.y/4.9.y/4.14.y]
Merging this from stable into "Android Common Kernel" trees that were built with AOSP GCC 4.9, I expect this to break some builds. Arnd, IIRC did you mention that AOSP GCC had picked up a fix? If so, did you verify that via disassembly, or gerrit patch file?
(AOSP GCC 4.9: https://android.googlesource.com/platform/prebuilts/gcc/linux-x86/aarch64/aarch64-linux-android-4.9/
master branch, roll back a few commits).
It looks like AOSP GCC #defines __android__ 1.
I'm not arguing against a backport, just trying to think through how we'll need to sort this out downstream. (Revert or patch on top that checks for __android__, if AOSP GCC does in fact have a fix.)
Quoted 25 lines
Signed-off-by Will Deacon <[email protected]>--- include/linux/compiler-gcc.h | 6 ++++++ 1 file changed, 6 insertions(+)include/linux/compiler-gcc.h +6
-1@@ -145,6 +145,12 @@#if GCC_VERSION <30200 # error Sorry, your compiler is too old - please upgrade it. +#elif defined(CONFIG_ARM64 ) &&GCC_VERSION <50100 +/* +* https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63293 +* https://lore.kernel.org/r/[email protected] +*/ +# error Sorry, your version of GCC is too old - please use 5.1 or newer.#endif #if GCC_VERSION <30300 --2.30.0.284.gd98b1dd5eaa7-goog
Signature · 2 lines
Thanks, ~Nick Desaulniers
Quoted 31 lines · Nick Desaulniers
Quoted 13 lines · Will Deacon
commit
dca5244d2f5b94f1809f0c02a549edf41ccd5493upstream.GCC versions >= 4.9 and < 5.1 have been shown to emit memory references beyond the stack pointer, resulting in memory corruption if an interrupt is taken after the stack pointer has been adjusted but before the reference has been executed. This leads to subtle, infrequent data corruption such as the EXT4 problems reported by Russell King at the link below.
Life is too short for buggy compilers, so raise the minimum GCC version required by arm64 to 5.1.
Quoted 16 lines
Reported-by Russell King <[email protected]>Suggested-by Arnd Bergmann <[email protected]>Signed-off-by Will Deacon <[email protected]>Tested-by Nathan Chancellor <[email protected]>Reviewed-by Nick Desaulniers <[email protected]>Reviewed-by Nathan Chancellor <[email protected]>Acked-by Linus Torvalds <[email protected]>Cc <[email protected]> # 4.4.y, 4.9.y and 4.14.y onlyCc Theodore Ts'o <[email protected]>Cc Florian Weimer <[email protected]>Cc Peter Zijlstra <[email protected]>Cc Nick Desaulniers <[email protected]>Signed-off-by Catalin Marinas <[email protected]>[will: backport to 4.4.y/4.9.y/4.14.y]
Quoted 8 lines
Merging this from stable into "Android Common Kernel" trees that were built with AOSP GCC 4.9, I expect this to break some builds. Arnd, IIRC did you mention that AOSP GCC had picked up a fix? If so, did you verify that via disassembly, or gerrit patch file?
(AOSP GCC 4.9: https://android.googlesource.com/platform/prebuilts/gcc/linux-x86/aarch64/aarch64-linux-android-4.9/
master branch, roll back a few commits).
It looks like AOSP GCC#defines __android__ 1.
It seems like this is the source for that toolchain?
https://android.googlesource.com/toolchain/gcc
If so, it looks like that patch was picked up in this commit.
https://android.googlesource.com/toolchain/gcc/+/5ae0308a147ec3f6502fd321860524e634a647a6
Cheers,
Nathan
Quoted 6 lines · Nathan Chancellor
Quoted 5 lines · Nick Desaulniers
Merging this from stable into "Android Common Kernel" trees that were built with AOSP GCC 4.9, I expect this to break some builds. Arnd, IIRC did you mention that AOSP GCC had picked up a fix? If so, did you verify that via disassembly, or gerrit patch file?
The only information I had was the fact that the gcc bug tracker mentioned it being picked up into the Android gcc and gcc-linaro. I verified that it was present in gcc-linaro, but did not also check the Android sources.
Quoted 3 lines
If so, it looks like that patch was picked up in this commit.
https://android.googlesource.com/toolchain/gcc/+/5ae0308a147ec3f6502fd321860524e634a647a6
Right.
Arnd