Will Deacon 760bfb47c3 arm64: fault: Route pte translation faults via do_translation_fault ... We currently route pte translation faults via do_page_fault, which elides the address check against TASK_SIZE before invoking the mm fault handling code. However, this can cause issues with the path walking code in conjunction with our word-at-a-time implementation because load_unaligned_zeropad can end up faulting in kernel space if it reads across a page boundary and runs into a page fault (e.g. by attempting to read from a guard region). In the case of such a fault, load_unaligned_zeropad has registered a fixup to shift the valid data and pad with zeroes, however the abort is reported as a level 3 translation fault and we dispatch it straight to do_page_fault, despite it being a kernel address. This results in calling a sleeping function from atomic context: BUG: sleeping function called from invalid context at arch/arm64/mm/fault.c:313 in_atomic(): 0, irqs_disabled(): 0, pid: 10290 Internal error: Oops - BUG: 0 [#1] PREEMPT SMP [...] [<ffffff8e016cd0cc>] ___might_sleep+0x134/0x144 [<ffffff8e016cd158>] __might_sleep+0x7c/0x8c [<ffffff8e016977f0>] do_page_fault+0x140/0x330 [<ffffff8e01681328>] do_mem_abort+0x54/0xb0 Exception stack(0xfffffffb20247a70 to 0xfffffffb20247ba0) [...] [<ffffff8e016844fc>] el1_da+0x18/0x78 [<ffffff8e017f399c>] path_parentat+0x44/0x88 [<ffffff8e017f4c9c>] filename_parentat+0x5c/0xd8 [<ffffff8e017f5044>] filename_create+0x4c/0x128 [<ffffff8e017f59e4>] SyS_mkdirat+0x50/0xc8 [<ffffff8e01684e30>] el0_svc_naked+0x24/0x28 Code: 36380080 d5384100 f9400800 9402566d (d4210000) ---[ end trace 2d01889f2bca9b9f ]--- Fix this by dispatching all translation faults to do_translation_faults, which avoids invoking the page fault logic for faults on kernel addresses. Cc: <stable@vger.kernel.org> Reported-by: Ankit Jain <ankijain@codeaurora.org> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>		2017-09-29 16:47:40 +01:00
..
cache.S	arm64: Implement pmem API support	2017-08-09 12:15:45 +01:00
context.c
copypage.c
dma-mapping.c	arm64: dma-mapping: Mark atomic_pool as __ro_after_init	2017-08-21 16:24:53 +01:00
dump.c
extable.c
fault.c	arm64: fault: Route pte translation faults via do_translation_fault	2017-09-29 16:47:40 +01:00
flush.c	arm64: fix pmem interface definition	2017-08-10 18:13:59 +01:00
hugetlbpage.c	arm64: hugetlb: Cleanup setup_hugepagesz	2017-08-22 17:47:12 +01:00
init.c
ioremap.c
kasan_init.c
Makefile
mmap.c
mmu.c
numa.c
pageattr.c
pgd.c
physaddr.c
proc.S
ptdump_debugfs.c