diff options
| author | Arnd Bergmann <arnd@arndb.de> | 2019-08-03 07:49:02 +0300 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2019-08-03 17:02:01 +0300 |
| commit | ee38d94a0ad89890b770f6c876263cf9fcbfde84 (patch) | |
| tree | 1edc9c9137d2412e35dc9f332dce76e1ff96e99d | |
| parent | af700eaed0564d5d3963a7a51cb0843629d7fe3d (diff) | |
| download | linux-ee38d94a0ad89890b770f6c876263cf9fcbfde84.tar.xz | |
page flags: prioritize kasan bits over last-cpuid
ARM64 randdconfig builds regularly run into a build error, especially
when NUMA_BALANCING and SPARSEMEM are enabled but not SPARSEMEM_VMEMMAP:
#error "KASAN: not enough bits in page flags for tag"
The last-cpuid bits are already contitional on the available space, so
the result of the calculation is a bit random on whether they were
already left out or not.
Adding the kasan tag bits before last-cpuid makes it much more likely to
end up with a successful build here, and should be reliable for
randconfig at least, as long as that does not randomize NR_CPUS or
NODES_SHIFT but uses the defaults.
In order for the modified check to not trigger in the x86 vdso32 code
where all constants are wrong (building with -m32), enclose all the
definitions with an #ifdef.
[arnd@arndb.de: build fix]
Link: http://lkml.kernel.org/r/CAK8P3a3Mno1SWTcuAOT0Wa9VS15pdU6EfnkxLbDpyS55yO04+g@mail.gmail.com
Link: http://lkml.kernel.org/r/20190722115520.3743282-1-arnd@arndb.de
Link: https://lore.kernel.org/lkml/20190618095347.3850490-1-arnd@arndb.de/
Fixes: 2813b9c02962 ("kasan, mm, arm64: tag non slab memory allocated via pagealloc")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Andrey Konovalov <andreyknvl@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| -rw-r--r-- | arch/mips/vdso/vdso.h | 1 | ||||
| -rw-r--r-- | include/linux/page-flags-layout.h | 18 |
2 files changed, 12 insertions, 7 deletions
diff --git a/arch/mips/vdso/vdso.h b/arch/mips/vdso/vdso.h index 14b1931be69c..b65b169778e3 100644 --- a/arch/mips/vdso/vdso.h +++ b/arch/mips/vdso/vdso.h @@ -9,6 +9,7 @@ #if _MIPS_SIM != _MIPS_SIM_ABI64 && defined(CONFIG_64BIT) /* Building 32-bit VDSO for the 64-bit kernel. Fake a 32-bit Kconfig. */ +#define BUILD_VDSO32_64 #undef CONFIG_64BIT #define CONFIG_32BIT 1 #ifndef __ASSEMBLY__ diff --git a/include/linux/page-flags-layout.h b/include/linux/page-flags-layout.h index 1dda31825ec4..71283739ffd2 100644 --- a/include/linux/page-flags-layout.h +++ b/include/linux/page-flags-layout.h @@ -32,6 +32,7 @@ #endif /* CONFIG_SPARSEMEM */ +#ifndef BUILD_VDSO32_64 /* * page->flags layout: * @@ -76,20 +77,22 @@ #define LAST_CPUPID_SHIFT 0 #endif -#if SECTIONS_WIDTH+ZONES_WIDTH+NODES_SHIFT+LAST_CPUPID_SHIFT <= BITS_PER_LONG - NR_PAGEFLAGS +#ifdef CONFIG_KASAN_SW_TAGS +#define KASAN_TAG_WIDTH 8 +#else +#define KASAN_TAG_WIDTH 0 +#endif + +#if SECTIONS_WIDTH+ZONES_WIDTH+NODES_SHIFT+LAST_CPUPID_SHIFT+KASAN_TAG_WIDTH \ + <= BITS_PER_LONG - NR_PAGEFLAGS #define LAST_CPUPID_WIDTH LAST_CPUPID_SHIFT #else #define LAST_CPUPID_WIDTH 0 #endif -#ifdef CONFIG_KASAN_SW_TAGS -#define KASAN_TAG_WIDTH 8 #if SECTIONS_WIDTH+NODES_WIDTH+ZONES_WIDTH+LAST_CPUPID_WIDTH+KASAN_TAG_WIDTH \ > BITS_PER_LONG - NR_PAGEFLAGS -#error "KASAN: not enough bits in page flags for tag" -#endif -#else -#define KASAN_TAG_WIDTH 0 +#error "Not enough bits in page flags" #endif /* @@ -104,4 +107,5 @@ #define LAST_CPUPID_NOT_IN_PAGE_FLAGS #endif +#endif #endif /* _LINUX_PAGE_FLAGS_LAYOUT */ |