3.16.63-rc1 review patch. If anyone has any objections, please let me know.
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From: "Kirill A. Shutemov" kirill.shutemov@linux.intel.com
commit 70f1528747651b20c7769d3516ade369f9963237 upstream.
Recent PAT patchset has caused issue on 32-bit PAE machines:
page:eea45000 count:0 mapcount:-128 mapping: (null) index:0x0 flags: 0x40000000() page dumped because: VM_BUG_ON_PAGE(page_mapcount(page) < 0) ------------[ cut here ]------------ kernel BUG at /home/build/linux-boris/mm/huge_memory.c:1485! invalid opcode: 0000 [#1] SMP [...] Call Trace: unmap_single_vma ? __wake_up unmap_vmas unmap_region do_munmap vm_munmap SyS_munmap do_fast_syscall_32 ? __do_page_fault sysenter_past_esp Code: ... EIP: [<c11bde80>] zap_huge_pmd+0x240/0x260 SS:ESP 0068:f6459d98
The problem is in pmd_pfn_mask() and pmd_flags_mask(). These helpers use PMD_PAGE_MASK to calculate resulting mask. PMD_PAGE_MASK is 'unsigned long', not 'unsigned long long' as phys_addr_t is on 32-bit PAE (ARCH_PHYS_ADDR_T_64BIT). As a result, the upper bits of resulting mask get truncated.
pud_pfn_mask() and pud_flags_mask() aren't problematic since we don't have PUD page table level on 32-bit systems, but it's reasonable to keep them consistent with PMD counterpart.
Introduce PHYSICAL_PMD_PAGE_MASK and PHYSICAL_PUD_PAGE_MASK in addition to existing PHYSICAL_PAGE_MASK and reworks helpers to use them.
Reported-and-Tested-by: Boris Ostrovsky boris.ostrovsky@oracle.com Signed-off-by: Kirill A. Shutemov kirill.shutemov@linux.intel.com [ Fix -Woverflow warnings from the realmode code. ] Signed-off-by: Borislav Petkov bp@suse.de Reviewed-by: Toshi Kani toshi.kani@hpe.com Cc: Andrew Morton akpm@linux-foundation.org Cc: Andy Lutomirski luto@amacapital.net Cc: Borislav Petkov bp@alien8.de Cc: Brian Gerst brgerst@gmail.com Cc: Denys Vlasenko dvlasenk@redhat.com Cc: H. Peter Anvin hpa@zytor.com Cc: Jürgen Gross jgross@suse.com Cc: Linus Torvalds torvalds@linux-foundation.org Cc: Mel Gorman mgorman@suse.de Cc: Peter Zijlstra peterz@infradead.org Cc: Thomas Gleixner tglx@linutronix.de Cc: elliott@hpe.com Cc: konrad.wilk@oracle.com Cc: linux-mm linux-mm@kvack.org Fixes: f70abb0fc3da ("x86/asm: Fix pud/pmd interfaces to handle large PAT bit") Link: http://lkml.kernel.org/r/1448878233-11390-2-git-send-email-bp@alien8.de Signed-off-by: Ingo Molnar mingo@kernel.org
Signed-off-by: Ingo Molnar mingo@kernel.org Signed-off-by: Ben Hutchings ben@decadent.org.uk --- arch/x86/boot/boot.h | 1 - arch/x86/boot/video-mode.c | 2 ++ arch/x86/boot/video.c | 2 ++ arch/x86/include/asm/page_types.h | 16 +++++++++------- arch/x86/include/asm/pgtable_types.h | 14 ++++---------- arch/x86/include/asm/x86_init.h | 1 - 6 files changed, 17 insertions(+), 19 deletions(-)
--- a/arch/x86/boot/boot.h +++ b/arch/x86/boot/boot.h @@ -23,7 +23,6 @@ #include <stdarg.h> #include <linux/types.h> #include <linux/edd.h> -#include <asm/boot.h> #include <asm/setup.h> #include "bitops.h" #include "ctype.h" --- a/arch/x86/boot/video-mode.c +++ b/arch/x86/boot/video-mode.c @@ -19,6 +19,8 @@ #include "video.h" #include "vesa.h"
+#include <uapi/asm/boot.h> + /* * Common variables */ --- a/arch/x86/boot/video.c +++ b/arch/x86/boot/video.c @@ -13,6 +13,8 @@ * Select video mode */
+#include <uapi/asm/boot.h> + #include "boot.h" #include "video.h" #include "vesa.h" --- a/arch/x86/include/asm/page_types.h +++ b/arch/x86/include/asm/page_types.h @@ -9,19 +9,21 @@ #define PAGE_SIZE (_AC(1,UL) << PAGE_SHIFT) #define PAGE_MASK (~(PAGE_SIZE-1))
+#define PMD_PAGE_SIZE (_AC(1, UL) << PMD_SHIFT) +#define PMD_PAGE_MASK (~(PMD_PAGE_SIZE-1)) + +#define PUD_PAGE_SIZE (_AC(1, UL) << PUD_SHIFT) +#define PUD_PAGE_MASK (~(PUD_PAGE_SIZE-1)) + #define __PHYSICAL_MASK ((phys_addr_t)((1ULL << __PHYSICAL_MASK_SHIFT) - 1)) #define __VIRTUAL_MASK ((1UL << __VIRTUAL_MASK_SHIFT) - 1)
-/* Cast PAGE_MASK to a signed type so that it is sign-extended if +/* Cast *PAGE_MASK to a signed type so that it is sign-extended if virtual addresses are 32-bits but physical addresses are larger (ie, 32-bit PAE). */ #define PHYSICAL_PAGE_MASK (((signed long)PAGE_MASK) & __PHYSICAL_MASK) - -#define PMD_PAGE_SIZE (_AC(1, UL) << PMD_SHIFT) -#define PMD_PAGE_MASK (~(PMD_PAGE_SIZE-1)) - -#define PUD_PAGE_SIZE (_AC(1, UL) << PUD_SHIFT) -#define PUD_PAGE_MASK (~(PUD_PAGE_SIZE-1)) +#define PHYSICAL_PMD_PAGE_MASK (((signed long)PMD_PAGE_MASK) & __PHYSICAL_MASK) +#define PHYSICAL_PUD_PAGE_MASK (((signed long)PUD_PAGE_MASK) & __PHYSICAL_MASK)
#define HPAGE_SHIFT PMD_SHIFT #define HPAGE_SIZE (_AC(1,UL) << HPAGE_SHIFT) --- a/arch/x86/include/asm/pgtable_types.h +++ b/arch/x86/include/asm/pgtable_types.h @@ -332,17 +332,14 @@ static inline pmdval_t native_pmd_val(pm static inline pudval_t pud_pfn_mask(pud_t pud) { if (native_pud_val(pud) & _PAGE_PSE) - return PUD_PAGE_MASK & PHYSICAL_PAGE_MASK; + return PHYSICAL_PUD_PAGE_MASK; else return PTE_PFN_MASK; }
static inline pudval_t pud_flags_mask(pud_t pud) { - if (native_pud_val(pud) & _PAGE_PSE) - return ~(PUD_PAGE_MASK & (pudval_t)PHYSICAL_PAGE_MASK); - else - return ~PTE_PFN_MASK; + return ~pud_pfn_mask(pud); }
static inline pudval_t pud_flags(pud_t pud) @@ -353,17 +350,14 @@ static inline pudval_t pud_flags(pud_t p static inline pmdval_t pmd_pfn_mask(pmd_t pmd) { if (native_pmd_val(pmd) & _PAGE_PSE) - return PMD_PAGE_MASK & PHYSICAL_PAGE_MASK; + return PHYSICAL_PMD_PAGE_MASK; else return PTE_PFN_MASK; }
static inline pmdval_t pmd_flags_mask(pmd_t pmd) { - if (native_pmd_val(pmd) & _PAGE_PSE) - return ~(PMD_PAGE_MASK & (pmdval_t)PHYSICAL_PAGE_MASK); - else - return ~PTE_PFN_MASK; + return ~pmd_pfn_mask(pmd); }
static inline pmdval_t pmd_flags(pmd_t pmd) --- a/arch/x86/include/asm/x86_init.h +++ b/arch/x86/include/asm/x86_init.h @@ -1,7 +1,6 @@ #ifndef _ASM_X86_PLATFORM_H #define _ASM_X86_PLATFORM_H
-#include <asm/pgtable_types.h> #include <asm/bootparam.h>
struct mpc_bus;