From 985db026c34dfc45213649023d5505822a5dcd78 Mon Sep 17 00:00:00 2001 From: Christophe Leroy Date: Tue, 20 Aug 2024 19:23:47 +0200 Subject: [PATCH] powerpc/8xx: Copy kernel PGD entries into all PGDIRs In order to avoid having to select PGDIR at each TLB miss based on fault address, copy kernel PGD entries into all PGDIRs in pgd_alloc(). At first it will be used for ITLB misses for kernel TEXT, then for execmem then for kernel DATA. Signed-off-by: Christophe Leroy Signed-off-by: Michael Ellerman Link: https://msgid.link/c6d2bf5af2ea909071a85bdca8b1f5dc2df134a8.1724173828.git.christophe.leroy@csgroup.eu --- arch/powerpc/include/asm/nohash/pgalloc.h | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/arch/powerpc/include/asm/nohash/pgalloc.h b/arch/powerpc/include/asm/nohash/pgalloc.h index d06efac6d7aa..4ef780b291bc 100644 --- a/arch/powerpc/include/asm/nohash/pgalloc.h +++ b/arch/powerpc/include/asm/nohash/pgalloc.h @@ -19,8 +19,14 @@ static inline void tlb_flush_pgtable(struct mmu_gather *tlb, static inline pgd_t *pgd_alloc(struct mm_struct *mm) { - return kmem_cache_alloc(PGT_CACHE(PGD_INDEX_SIZE), + pgd_t *pgd = kmem_cache_alloc(PGT_CACHE(PGD_INDEX_SIZE), pgtable_gfp_flags(mm, GFP_KERNEL)); + +#ifdef CONFIG_PPC_8xx + memcpy(pgd + USER_PTRS_PER_PGD, swapper_pg_dir + USER_PTRS_PER_PGD, + (MAX_PTRS_PER_PGD - USER_PTRS_PER_PGD) * sizeof(pgd_t)); +#endif + return pgd; } static inline void pgd_free(struct mm_struct *mm, pgd_t *pgd)