From: Andrey Konovalov Date: Sat, 13 Mar 2021 05:08:13 +0000 (-0800) Subject: kasan: fix KASAN_STACK dependency for HW_TAGS X-Git-Tag: v5.12-rc3~12^2~7 X-Git-Url: https://git.kernel.dk/?a=commitdiff_plain;h=d9b571c885a8974fbb7d4ee639dbc643fd000f9e;p=linux-2.6-block.git kasan: fix KASAN_STACK dependency for HW_TAGS There's a runtime failure when running HW_TAGS-enabled kernel built with GCC on hardware that doesn't support MTE. GCC-built kernels always have CONFIG_KASAN_STACK enabled, even though stack instrumentation isn't supported by HW_TAGS. Having that config enabled causes KASAN to issue MTE-only instructions to unpoison kernel stacks, which causes the failure. Fix the issue by disallowing CONFIG_KASAN_STACK when HW_TAGS is used. (The commit that introduced CONFIG_KASAN_HW_TAGS specified proper dependency for CONFIG_KASAN_STACK_ENABLE but not for CONFIG_KASAN_STACK.) Link: https://lkml.kernel.org/r/59e75426241dbb5611277758c8d4d6f5f9298dac.1615215441.git.andreyknvl@google.com Fixes: 6a63a63ff1ac ("kasan: introduce CONFIG_KASAN_HW_TAGS") Signed-off-by: Andrey Konovalov Reported-by: Catalin Marinas Cc: Cc: Will Deacon Cc: Vincenzo Frascino Cc: Dmitry Vyukov Cc: Andrey Ryabinin Cc: Alexander Potapenko Cc: Marco Elver Cc: Peter Collingbourne Cc: Evgenii Stepanov Cc: Branislav Rankov Cc: Kevin Brodsky Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- diff --git a/lib/Kconfig.kasan b/lib/Kconfig.kasan index 624ae1df7984..fba9909e31b7 100644 --- a/lib/Kconfig.kasan +++ b/lib/Kconfig.kasan @@ -156,6 +156,7 @@ config KASAN_STACK_ENABLE config KASAN_STACK int + depends on KASAN_GENERIC || KASAN_SW_TAGS default 1 if KASAN_STACK_ENABLE || CC_IS_GCC default 0