On 22/08/2024 22:27, Darrick J. Wong wrote: > [...] >> >> + Control the ability of directly writing to mounted block >> + devices' page cache, i.e., allow / disallow writes that >> + bypasses the FS. This was implemented as a means to >> + prevent fuzzers to crash the kernel by breaking the > > "...from crashing the kernel by overwriting > the metadata underneath a mounted filesystem without its awareness." > >> + filesystem without its awareness, through direct block >> + device writes. Also prevents issues from direct writes > > You can do it with buffered writes to the block device pagecache too. > > "This also prevents destructive formatting of mounted filesystems by > naïve storage tooling that don't use O_EXCL." > > --D Thanks! Just sent the V2.