f4f451a16d
FSDAX page refcounts are 1-based, rather than 0-based: if refcount is 1, then the page is freed. The FSDAX pages can be pinned through GUP, then they will be unpinned via unpin_user_page() using a folio variant to put the page, however, folio variants did not consider this special case, the result will be to miss a wakeup event (like the user of __fuse_dax_break_layouts()). This results in a task being permanently stuck in TASK_INTERRUPTIBLE state. Since FSDAX pages are only possibly obtained by GUP users, so fix GUP instead of folio_put() to lower overhead. Link: https://lkml.kernel.org/r/20220705123532.283-1-songmuchun@bytedance.com Fixes: d8ddc099c6b3 ("mm/gup: Add gup_put_folio()") Signed-off-by: Muchun Song <songmuchun@bytedance.com> Suggested-by: Matthew Wilcox <willy@infradead.org> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: John Hubbard <jhubbard@nvidia.com> Cc: William Kucharski <william.kucharski@oracle.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Jan Kara <jack@suse.cz> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
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| acpi | ||
| asm-generic | ||
| clocksource | ||
| crypto | ||
| drm | ||
| dt-bindings | ||
| keys | ||
| kunit | ||
| kvm | ||
| linux | ||
| math-emu | ||
| media | ||
| memory | ||
| misc | ||
| net | ||
| pcmcia | ||
| ras | ||
| rdma | ||
| scsi | ||
| soc | ||
| sound | ||
| target | ||
| trace | ||
| uapi | ||
| ufs | ||
| vdso | ||
| video | ||
| xen | ||