Date: Tue, 4 Jun 2019 15:11:14 +0000 (UTC) From: Ruslan Bukin <br@FreeBSD.org> To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-stable@freebsd.org, svn-src-stable-12@freebsd.org Subject: svn commit: r348613 - stable/12/sys/riscv/riscv Message-ID: <201906041511.x54FBExp024906@repo.freebsd.org>
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Author: br Date: Tue Jun 4 15:11:14 2019 New Revision: 348613 URL: https://svnweb.freebsd.org/changeset/base/348613 Log: MFC 339774: o Add pmap lock around pmap_fault_fixup() to ensure other thread will not modify l3 pte after we loaded old value and before we stored new value. o Preset A(accessed), D(dirty) bits for kernel mappings. Sponsored by: DARPA, AFRL Modified: stable/12/sys/riscv/riscv/pmap.c Modified: stable/12/sys/riscv/riscv/pmap.c ============================================================================== --- stable/12/sys/riscv/riscv/pmap.c Tue Jun 4 13:45:30 2019 (r348612) +++ stable/12/sys/riscv/riscv/pmap.c Tue Jun 4 15:11:14 2019 (r348613) @@ -1923,16 +1923,21 @@ pmap_fault_fixup(pmap_t pmap, vm_offset_t va, vm_prot_ pt_entry_t orig_l3; pt_entry_t new_l3; pt_entry_t *l3; + int rv; + rv = 0; + + PMAP_LOCK(pmap); + l3 = pmap_l3(pmap, va); if (l3 == NULL) - return (0); + goto done; orig_l3 = pmap_load(l3); if ((orig_l3 & PTE_V) == 0 || ((prot & VM_PROT_WRITE) != 0 && (orig_l3 & PTE_W) == 0) || ((prot & VM_PROT_READ) != 0 && (orig_l3 & PTE_R) == 0)) - return (0); + goto done; new_l3 = orig_l3 | PTE_A; if ((prot & VM_PROT_WRITE) != 0) @@ -1941,7 +1946,8 @@ pmap_fault_fixup(pmap_t pmap, vm_offset_t va, vm_prot_ if (orig_l3 != new_l3) { pmap_load_store(l3, new_l3); pmap_invalidate_page(pmap, va); - return (1); + rv = 1; + goto done; } /* @@ -1949,7 +1955,10 @@ pmap_fault_fixup(pmap_t pmap, vm_offset_t va, vm_prot_ * the PTE shouldn't have resulted in a fault. */ - return (0); +done: + PMAP_UNLOCK(pmap); + + return (rv); } /* @@ -1992,6 +2001,8 @@ pmap_enter(pmap_t pmap, vm_offset_t va, vm_page_t m, v new_l3 |= PTE_W; if ((va >> 63) == 0) new_l3 |= PTE_U; + else + new_l3 |= PTE_A | PTE_D; new_l3 |= (pn << PTE_PPN0_S); if ((flags & PMAP_ENTER_WIRED) != 0)
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