trešd., 2022. g. 2. febr., plkst. 21:13 — lietotājs Matthew Wilcox (<willy@xxxxxxxxxxxxx>) rakstīja: > > On Wed, Feb 02, 2022 at 07:15:14PM +0200, Dāvis Mosāns wrote: > > I have a corrupted file on BTRFS which has CoW disabled thus no > > checksum. Trying to read this file causes the process to get stuck > > forever. It doesn't return EIO. > > > > How can I find out why it gets stuck? > > > $ cat /proc/3449/stack | ./scripts/decode_stacktrace.sh vmlinux > > folio_wait_bit_common (mm/filemap.c:1314) > > filemap_get_pages (mm/filemap.c:2622) > > filemap_read (mm/filemap.c:2676) > > new_sync_read (fs/read_write.c:401 (discriminator 1)) > > folio_wait_bit_common() is where it waits for the page to be unlocked. > Probably the problem is that btrfs isn't unlocking the page on > seeing the error, so you don't get the -EIO returned? Yeah, but how to find where that happens. Anyway by pure luck I found memcpy that wrote outside of allocated memory and fixing that solved this issue but I still don't know how to debug this properly.
