aboutsummaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorUros Bizjak <[email protected]>2023-10-09 17:13:48 +0200
committerIngo Molnar <[email protected]>2023-10-10 23:57:35 +0200
commite29aad08b1da7772b362537be32335c0394e65fe (patch)
tree73b1e5608b9755f062779660e650b1a7df6a1efd
parentca4256348660cb2162668ec3d13d1f921d05374a (diff)
x86/percpu: Disable named address spaces for KASAN
-fsanitize=kernel-address (KASAN) is at the moment incompatible with named address spaces - see GCC PR sanitizer/111736: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111736 GCC is doing a KASAN check on a percpu address which it shouldn't do, and didn't used to do because we did the access using inline asm. But now that GCC does the accesses as normal (albeit special address space) memory accesses, the KASAN code triggers on them too, and it all goes to hell in a handbasket very quickly. Those percpu accessor functions need to disable any KASAN checking or other sanitizer checking. Not on the percpu address, because that's not a "real" address, it's obviously just the offset from the segment register. And GCC should probably not have generated such code in the first place, so arguably this is a bug with -fsanitize=kernel-address. The patch also removes a stale dependency on CONFIG_SMP. Reported-by: kernel test robot <[email protected]> Signed-off-by: Uros Bizjak <[email protected]> Signed-off-by: Ingo Molnar <[email protected]> Cc: Andy Lutomirski <[email protected]> Cc: Brian Gerst <[email protected]> Cc: Denys Vlasenko <[email protected]> Cc: H. Peter Anvin <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Josh Poimboeuf <[email protected]> Link: https://lore.kernel.org/r/[email protected] Closes: https://lore.kernel.org/oe-lkp/[email protected]
-rw-r--r--arch/x86/Kconfig7
1 files changed, 6 insertions, 1 deletions
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index ecb256954351..54e79d3061f9 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -2393,7 +2393,12 @@ config CC_HAS_NAMED_AS
config USE_X86_SEG_SUPPORT
def_bool y
- depends on CC_HAS_NAMED_AS && SMP
+ depends on CC_HAS_NAMED_AS
+ #
+ # -fsanitize=kernel-address (KASAN) is at the moment incompatible
+ # with named address spaces - see GCC PR sanitizer/111736.
+ #
+ depends on !KASAN
config CC_HAS_SLS
def_bool $(cc-option,-mharden-sls=all)