[$] Handling I/O errors in the kernel

The kernel's handling of I/O errors was the topic of a discussion led byMatthew Wilcox at the 2018 Linux Storage, Filesystem, and Memory-ManagementSummit (LSFMM) in a combined storage and filesystem track session. At the start, he asked: "how is our error handling andwhat do we plan to do about it?" That led to a discussion between thedevelopers present on the kinds of errors that can occur and onways to handle them.