Re: [PATCH 04/15] arm64: switch to generic version of pte allocation
From: Mark Rutland <mark.rutland@arm.com>
Date: 2019-05-03 10:05:20
Also in:
linux-alpha, linux-arch, linux-mips, linux-riscv, linux-um, linuxppc-dev, lkml
Hi, On Thu, May 02, 2019 at 06:28:31PM +0300, Mike Rapoport wrote:
The PTE allocations in arm64 are identical to the generic ones modulo the GFP flags. Using the generic pte_alloc_one() functions ensures that the user page tables are allocated with __GFP_ACCOUNT set. The arm64 definition of PGALLOC_GFP is removed and replaced with GFP_PGTABLE_USER for p[gum]d_alloc_one() and for KVM memory cache. The mappings created with create_pgd_mapping() are now using GFP_PGTABLE_KERNEL. The conversion to the generic version of pte_free_kernel() removes the NULL check for pte. The pte_free() version on arm64 is identical to the generic one and can be simply dropped. Signed-off-by: Mike Rapoport <redacted> --- arch/arm64/include/asm/pgalloc.h | 43 ++++------------------------------------ arch/arm64/mm/mmu.c | 2 +- arch/arm64/mm/pgd.c | 4 ++-- virt/kvm/arm/mmu.c | 2 +- 4 files changed, 8 insertions(+), 43 deletions(-)
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quoted hunk ↗ jump to hunk
diff --git a/arch/arm64/mm/pgd.c b/arch/arm64/mm/pgd.c index 289f911..2ef1a53 100644 --- a/arch/arm64/mm/pgd.c +++ b/arch/arm64/mm/pgd.c@@ -31,9 +31,9 @@ static struct kmem_cache *pgd_cache __ro_after_init; pgd_t *pgd_alloc(struct mm_struct *mm) { if (PGD_SIZE == PAGE_SIZE) - return (pgd_t *)__get_free_page(PGALLOC_GFP); + return (pgd_t *)__get_free_page(GFP_PGTABLE_USER); else - return kmem_cache_alloc(pgd_cache, PGALLOC_GFP); + return kmem_cache_alloc(pgd_cache, GFP_PGTABLE_USER); }
In efi_virtmap_init() we use pgd_alloc() to allocate a pgd for EFI runtime services, which we map with a special kernel page table. I'm not sure if accounting that is problematic, as it's allocated in a kernel thread off the back of an early_initcall. Just to check, Is that sound, or do we need a pgd_alloc_kernel()? Thanks, Mark. _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel