summaryrefslogtreecommitdiff
path: root/arch/x86/include/asm/pgtable_32.h
diff options
context:
space:
mode:
authorArnd Bergmann <arnd@arndb.de>2019-07-10 15:04:55 +0200
committerThomas Gleixner <tglx@linutronix.de>2019-07-10 17:19:58 +0200
commit26515699863d68058e290e18e83f444925920be5 (patch)
tree6d55778feb7272b0317e6d9484a6efa184252094 /arch/x86/include/asm/pgtable_32.h
parentecc606103837b98a2b665e8f14e533a6c72bbdc0 (diff)
x86/pgtable/32: Fix LOWMEM_PAGES constant
clang points out that the computation of LOWMEM_PAGES causes a signed integer overflow on 32-bit x86: arch/x86/kernel/head32.c:83:20: error: signed shift result (0x100000000) requires 34 bits to represent, but 'int' only has 32 bits [-Werror,-Wshift-overflow] (PAGE_TABLE_SIZE(LOWMEM_PAGES) << PAGE_SHIFT); ^~~~~~~~~~~~ arch/x86/include/asm/pgtable_32.h:109:27: note: expanded from macro 'LOWMEM_PAGES' #define LOWMEM_PAGES ((((2<<31) - __PAGE_OFFSET) >> PAGE_SHIFT)) ~^ ~~ arch/x86/include/asm/pgtable_32.h:98:34: note: expanded from macro 'PAGE_TABLE_SIZE' #define PAGE_TABLE_SIZE(pages) ((pages) / PTRS_PER_PGD) Use the _ULL() macro to make it a 64-bit constant. Fixes: 1e620f9b23e5 ("x86/boot/32: Convert the 32-bit pgtable setup code from assembly to C") Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20190710130522.1802800-1-arnd@arndb.de
Diffstat (limited to 'arch/x86/include/asm/pgtable_32.h')
-rw-r--r--arch/x86/include/asm/pgtable_32.h2
1 files changed, 1 insertions, 1 deletions
diff --git a/arch/x86/include/asm/pgtable_32.h b/arch/x86/include/asm/pgtable_32.h
index 4fe9e7fc74d3..c78da8eda8f2 100644
--- a/arch/x86/include/asm/pgtable_32.h
+++ b/arch/x86/include/asm/pgtable_32.h
@@ -106,6 +106,6 @@ do { \
* with only a host target support using a 32-bit type for internal
* representation.
*/
-#define LOWMEM_PAGES ((((2<<31) - __PAGE_OFFSET) >> PAGE_SHIFT))
+#define LOWMEM_PAGES ((((_ULL(2)<<31) - __PAGE_OFFSET) >> PAGE_SHIFT))
#endif /* _ASM_X86_PGTABLE_32_H */