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| author |   Anshuman Khandual <anshuman.khandual@arm.com> | 2020-06-03 16:00:56 -0700 |
|---|---|---|
| committer |   Linus Torvalds <torvalds@linux-foundation.org> | 2020-06-03 20:09:46 -0700 |
| commit | be51e3fde5c10f269c065fdca2caf28e4708e21e (patch) | |
| tree | 6c7eb90cbbdd6502462a69a45cc7af604a755c56 /include/asm-generic | |
| parent | mm/hugetlb: avoid unnecessary check on pud and pmd entry in huge_pte_offset (diff) | |
| download | wireguard-linux-be51e3fde5c10f269c065fdca2caf28e4708e21e.tar.xz wireguard-linux-be51e3fde5c10f269c065fdca2caf28e4708e21e.zip | |
arm64/mm: drop __HAVE_ARCH_HUGE_PTEP_GET
Patch series "mm/hugetlb: Add some new generic fallbacks", v3.
This series adds the following new generic fallbacks. Before that it
drops __HAVE_ARCH_HUGE_PTEP_GET from arm64 platform.
1. is_hugepage_only_range()
2. arch_clear_hugepage_flags()
After this arm (32 bit) remains the sole platform defining it's own
huge_ptep_get() via __HAVE_ARCH_HUGE_PTEP_GET.
This patch (of 3):
Platform specific huge_ptep_get() is required only when fetching the huge
PTE involves more than just dereferencing the page table pointer. This is
not the case on arm64 platform. Hence huge_ptep_pte() can be dropped
along with it's __HAVE_ARCH_HUGE_PTEP_GET subscription. Before that, it
updates the generic huge_ptep_get() with READ_ONCE() which will prevent
known page table issues with THP on arm64.
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Helge Deller <deller@gmx.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Rich Felker <dalias@libc.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Link: http://lkml.kernel.org/r/1588907271-11920-1-git-send-email-anshuman.khandual@arm.com
Link: http://lkml.kernel.org/r//1506527369-19535-1-git-send-email-will.deacon@arm.com/
Link: http://lkml.kernel.org/r/1588907271-11920-2-git-send-email-anshuman.khandual@arm.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'include/asm-generic')
| -rw-r--r-- | include/asm-generic/hugetlb.h | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/include/asm-generic/hugetlb.h b/include/asm-generic/hugetlb.h index 822f433ac95c..40f85decc2ee 100644 --- a/include/asm-generic/hugetlb.h +++ b/include/asm-generic/hugetlb.h @@ -122,7 +122,7 @@ static inline int huge_ptep_set_access_flags(struct vm_area_struct *vma, #ifndef __HAVE_ARCH_HUGE_PTEP_GET static inline pte_t huge_ptep_get(pte_t *ptep) { - return *ptep; + return READ_ONCE(*ptep); } #endif |