From: Alistair Popple apopple@nvidia.com
mainline inclusion from mainline-v6.1-rc7 commit 4a955bed882e734807024afd8f53213d4c61ff97 category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I6BG56 CVE: NA
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i...
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The migrate_to_ram() callback should always succeed, but in rare cases can fail usually returning VM_FAULT_SIGBUS. Commit 16ce101db85d ("mm/memory.c: fix race when faulting a device private page") incorrectly stopped passing the return code up the stack. Fix this by setting the ret variable, restoring the previous behaviour on migrate_to_ram() failure.
Link: https://lkml.kernel.org/r/20221114115537.727371-1-apopple@nvidia.com Fixes: 16ce101db85d ("mm/memory.c: fix race when faulting a device private page") Signed-off-by: Alistair Popple apopple@nvidia.com Acked-by: David Hildenbrand david@redhat.com Reviewed-by: Felix Kuehling Felix.Kuehling@amd.com Cc: Ralph Campbell rcampbell@nvidia.com Cc: John Hubbard jhubbard@nvidia.com Cc: Alex Sierra alex.sierra@amd.com Cc: Ben Skeggs bskeggs@redhat.com Cc: Lyude Paul lyude@redhat.com Cc: Jason Gunthorpe jgg@nvidia.com Cc: Michael Ellerman mpe@ellerman.id.au Signed-off-by: Andrew Morton akpm@linux-foundation.org Signed-off-by: Ma Wupeng mawupeng1@huawei.com Reviewed-by: Kefeng Wang wangkefeng.wang@huawei.com Reviewed-by: tong tiangen tongtiangen@huawei.com Signed-off-by: Jialin Zhang zhangjialin11@huawei.com --- mm/memory.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/mm/memory.c b/mm/memory.c index badf913062a2..732895edbb67 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -3415,7 +3415,7 @@ vm_fault_t do_swap_page(struct vm_fault *vmf) */ get_page(vmf->page); pte_unmap_unlock(vmf->pte, vmf->ptl); - vmf->page->pgmap->ops->migrate_to_ram(vmf); + ret = vmf->page->pgmap->ops->migrate_to_ram(vmf); put_page(vmf->page); } else if (is_hwpoison_entry(entry)) { ret = VM_FAULT_HWPOISON;