Unverified Commit 8246601a authored by Jisheng Zhang's avatar Jisheng Zhang Committed by Palmer Dabbelt
Browse files

riscv: tlb: fix __p*d_free_tlb() 



If non-leaf PTEs I.E pmd, pud or p4d is modified, a sfence.vma is
a must for safe, imagine if an implementation caches the non-leaf
translation in TLB, although I didn't meet this HW so far, but it's
possible in theory.

Signed-off-by: default avatarJisheng Zhang <jszhang@kernel.org>
Fixes: c5e9b2c2 ("riscv: Improve tlb_flush()")
Link: https://lore.kernel.org/r/20231219175046.2496-2-jszhang@kernel.org


Signed-off-by: default avatarPalmer Dabbelt <palmer@rivosinc.com>
parent b85ea95d

arch/riscv/include/asm/pgalloc.h

+17 −3
Original line number Diff line number Diff line
@@ -95,7 +95,13 @@ static inline void pud_free(struct mm_struct *mm, pud_t *pud) 
		__pud_free(mm, pud);

}



#define __pud_free_tlb(tlb, pud, addr)  pud_free((tlb)->mm, pud)

#define __pud_free_tlb(tlb, pud, addr)					\

do {									\

	if (pgtable_l4_enabled) {					\

		pagetable_pud_dtor(virt_to_ptdesc(pud));		\

		tlb_remove_page_ptdesc((tlb), virt_to_ptdesc(pud));	\

	}								\

} while (0)



#define p4d_alloc_one p4d_alloc_one

static inline p4d_t *p4d_alloc_one(struct mm_struct *mm, unsigned long addr)
@@ -124,7 +130,11 @@ static inline void p4d_free(struct mm_struct *mm, p4d_t *p4d) 
		__p4d_free(mm, p4d);

}



#define __p4d_free_tlb(tlb, p4d, addr)  p4d_free((tlb)->mm, p4d)

#define __p4d_free_tlb(tlb, p4d, addr)					\

do {									\

	if (pgtable_l5_enabled)						\

		tlb_remove_page_ptdesc((tlb), virt_to_ptdesc(p4d));	\

} while (0)

#endif /* __PAGETABLE_PMD_FOLDED */



static inline void sync_kernel_mappings(pgd_t *pgd)
@@ -149,7 +159,11 @@ static inline pgd_t *pgd_alloc(struct mm_struct *mm) 


#ifndef __PAGETABLE_PMD_FOLDED



#define __pmd_free_tlb(tlb, pmd, addr)  pmd_free((tlb)->mm, pmd)

#define __pmd_free_tlb(tlb, pmd, addr)				\

do {								\

	pagetable_pmd_dtor(virt_to_ptdesc(pmd));		\

	tlb_remove_page_ptdesc((tlb), virt_to_ptdesc(pmd));	\

} while (0)



#endif /* __PAGETABLE_PMD_FOLDED */