a7892f32cc
These mappings are in fact special and require special handling in privcmd, which already exists. Failure to mark the PTE as special on arm64 causes all sorts of bad PTE fun. e.g. e.g.: BUG: Bad page map in process xl pte:e0004077b33f53 pmd:4079575003 page:ffffffbce1a2f328 count:1 mapcount:-1 mapping: (null) index:0x0 page flags: 0x4000000000000014(referenced|dirty) addr:0000007fb5259000 vm_flags:040644fa anon_vma: (null) mapping:ffffffc03a6fda58 index:0 vma->vm_ops->fault: privcmd_fault+0x0/0x38 vma->vm_file->f_op->mmap: privcmd_mmap+0x0/0x2c CPU: 0 PID: 2657 Comm: xl Not tainted 3.12.0+ #102 Call trace: [<ffffffc0000880f8>] dump_backtrace+0x0/0x12c [<ffffffc000088238>] show_stack+0x14/0x1c [<ffffffc0004b67e0>] dump_stack+0x70/0x90 [<ffffffc000125690>] print_bad_pte+0x12c/0x1bc [<ffffffc0001268f4>] unmap_single_vma+0x4cc/0x700 [<ffffffc0001273b4>] unmap_vmas+0x68/0xb4 [<ffffffc00012c050>] unmap_region+0xcc/0x1d4 [<ffffffc00012df20>] do_munmap+0x218/0x314 [<ffffffc00012e060>] vm_munmap+0x44/0x64 [<ffffffc00012ed78>] SyS_munmap+0x24/0x34 Where unmap_single_vma contains inlined -> unmap_page_range -> zap_pud_range -> zap_pmd_range -> zap_pte_range -> print_bad_pte. Or: BUG: Bad page state in process xl pfn:4077b4d page:ffffffbce1a2f8d8 count:0 mapcount:-1 mapping: (null) index:0x0 page flags: 0x4000000000000014(referenced|dirty) Modules linked in: CPU: 0 PID: 2657 Comm: xl Tainted: G B 3.12.0+ #102 Call trace: [<ffffffc0000880f8>] dump_backtrace+0x0/0x12c [<ffffffc000088238>] show_stack+0x14/0x1c [<ffffffc0004b67e0>] dump_stack+0x70/0x90 [<ffffffc00010f798>] bad_page+0xc4/0x110 [<ffffffc00010f8b4>] free_pages_prepare+0xd0/0xd8 [<ffffffc000110e94>] free_hot_cold_page+0x28/0x178 [<ffffffc000111460>] free_hot_cold_page_list+0x38/0x60 [<ffffffc000114cf0>] release_pages+0x190/0x1dc [<ffffffc00012c0e0>] unmap_region+0x15c/0x1d4 [<ffffffc00012df20>] do_munmap+0x218/0x314 [<ffffffc00012e060>] vm_munmap+0x44/0x64 [<ffffffc00012ed78>] SyS_munmap+0x24/0x34 x86 already gets this correct. 32-bit arm gets away with this because there is not PTE_SPECIAL bit in the PTE there and the vm_normal_page fallback path does the right thing. Signed-off-by: Ian Campbell <ian.campbell@citrix.com> Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> |
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| .. | ||
| enlighten.c | ||
| grant-table.c | ||
| hypercall.S | ||
| Makefile | ||
| mm.c | ||
| p2m.c | ||