From this webpage screenshot, we can extract the following key information about the vulnerability: 1. Vulnerability Description: - Issue: When using shmem files, if the size of the PMD-sized page cache exceeds , an error may occur. - Cause: When the PMD-sized page cache size is greater than , the page cache for shmem files cannot be supported, leading to errors. 2. Error Messages: - Warning Message: In , a warning is triggered when the PMD-sized page cache size exceeds . - Error Message: In , an error is triggered under the same condition. 3. Fix Method: - Solution: Disable PMD-sized page cache in shmem files when is greater than . - Fix Code: In , modify the function to return when exceeds . 4. Related Links: - Link: https://lkml.kernel.org/r/20240627003953.1262512-5-gshan@redhat.com - Fix Commit: 6b24ca4a1a8d 5. Authors and Contributors: - Author: Gavin Shan - Contributors: David Hildenbrand, Darrick J. Wong, Don Dutile, Hugh Dickins, Linus Torvalds, Matthew Wilcox, Ryan Roberts, William Kucharshi, Zhenyu Zhang, Andrew Morton 6. Patch Status: - Status: Fixed; the patch has been merged into the kernel. With this information, we can understand the background, impact, fix method, and related code changes for this vulnerability.