Author: cem Date: Thu Jul 16 23:29:26 2020 New Revision: 363266 URL: https://svnweb.freebsd.org/changeset/base/363266
Log: Revert r240317 to prevent leaking pmap entries Subsequent to r240317, kmem_free() was replaced with kva_free() (r254025). kva_free() releases the KVA allocation for the mapped region, but no longer clears the pmap (pagetable) entries. An affected pmap_unmapdev operation would leave the still-pmap'd VA space free for allocation by other KVA consumers. However, this bug easily avoided notice for ~7 years because most devices (1) never call pmap_unmapdev and (2) on amd64, mostly fit within the DMAP and do not need KVA allocations. Other affected arch are less popular: i386, MIPS, and PowerPC. Arm64, arm32, and riscv are not affected. Reported by: Don Morris <dgmorris AT earthlink.net> Submitted by: Don Morris (amd64 part) Reviewed by: kib, markj, Don (!amd64 parts) MFC after: I don't intend to, but you might want to Sponsored by: Dell Isilon Differential Revision: https://reviews.freebsd.org/D25689 Modified: head/sys/amd64/amd64/pmap.c head/sys/i386/i386/pmap.c head/sys/mips/mips/pmap.c head/sys/powerpc/aim/mmu_oea.c head/sys/powerpc/aim/mmu_oea64.c head/sys/powerpc/aim/mmu_radix.c head/sys/powerpc/booke/pmap.c Modified: head/sys/amd64/amd64/pmap.c ============================================================================== --- head/sys/amd64/amd64/pmap.c Thu Jul 16 23:05:18 2020 (r363265) +++ head/sys/amd64/amd64/pmap.c Thu Jul 16 23:29:26 2020 (r363266) @@ -8279,8 +8279,10 @@ pmap_unmapdev(vm_offset_t va, vm_size_t size) return; } } - if (pmap_initialized) + if (pmap_initialized) { + pmap_qremove(va, atop(size)); kva_free(va, size); + } } /* Modified: head/sys/i386/i386/pmap.c ============================================================================== --- head/sys/i386/i386/pmap.c Thu Jul 16 23:05:18 2020 (r363265) +++ head/sys/i386/i386/pmap.c Thu Jul 16 23:29:26 2020 (r363266) @@ -5538,8 +5538,10 @@ __CONCAT(PMTYPE, unmapdev)(vm_offset_t va, vm_size_t s return; } } - if (pmap_initialized) + if (pmap_initialized) { + pmap_qremove(va, atop(size)); kva_free(va, size); + } } /* Modified: head/sys/mips/mips/pmap.c ============================================================================== --- head/sys/mips/mips/pmap.c Thu Jul 16 23:05:18 2020 (r363265) +++ head/sys/mips/mips/pmap.c Thu Jul 16 23:29:26 2020 (r363266) @@ -3264,6 +3264,7 @@ pmap_unmapdev(vm_offset_t va, vm_size_t size) base = trunc_page(va); offset = va & PAGE_MASK; size = roundup(size + offset, PAGE_SIZE); + pmap_qremove(base, atop(size)); kva_free(base, size); #endif } Modified: head/sys/powerpc/aim/mmu_oea.c ============================================================================== --- head/sys/powerpc/aim/mmu_oea.c Thu Jul 16 23:05:18 2020 (r363265) +++ head/sys/powerpc/aim/mmu_oea.c Thu Jul 16 23:29:26 2020 (r363266) @@ -2673,6 +2673,7 @@ moea_unmapdev(vm_offset_t va, vm_size_t size) base = trunc_page(va); offset = va & PAGE_MASK; size = roundup(offset + size, PAGE_SIZE); + moea_qremove(base, atop(size)); kva_free(base, size); } } Modified: head/sys/powerpc/aim/mmu_oea64.c ============================================================================== --- head/sys/powerpc/aim/mmu_oea64.c Thu Jul 16 23:05:18 2020 (r363265) +++ head/sys/powerpc/aim/mmu_oea64.c Thu Jul 16 23:29:26 2020 (r363266) @@ -2869,6 +2869,7 @@ moea64_unmapdev(vm_offset_t va, vm_size_t size) offset = va & PAGE_MASK; size = roundup2(offset + size, PAGE_SIZE); + moea64_qremove(base, atop(size)); kva_free(base, size); } Modified: head/sys/powerpc/aim/mmu_radix.c ============================================================================== --- head/sys/powerpc/aim/mmu_radix.c Thu Jul 16 23:05:18 2020 (r363265) +++ head/sys/powerpc/aim/mmu_radix.c Thu Jul 16 23:29:26 2020 (r363266) @@ -5846,8 +5846,10 @@ mmu_radix_unmapdev(vm_offset_t va, vm_size_t size) size = round_page(offset + size); va = trunc_page(va); - if (pmap_initialized) + if (pmap_initialized) { + mmu_radix_qremove(va, atop(size)); kva_free(va, size); + } } static __inline void Modified: head/sys/powerpc/booke/pmap.c ============================================================================== --- head/sys/powerpc/booke/pmap.c Thu Jul 16 23:05:18 2020 (r363265) +++ head/sys/powerpc/booke/pmap.c Thu Jul 16 23:29:26 2020 (r363266) @@ -2322,6 +2322,7 @@ mmu_booke_unmapdev(vm_offset_t va, vm_size_t size) base = trunc_page(va); offset = va & PAGE_MASK; size = roundup(offset + size, PAGE_SIZE); + mmu_booke_qremove(base, atop(size)); kva_free(base, size); } #endif _______________________________________________ svn-src-all@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/svn-src-all To unsubscribe, send any mail to "svn-src-all-unsubscr...@freebsd.org"
