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charset=US-ASCII Content-Transfer-Encoding: 7bit X-Spamd-Result: default: False [-3.51 / 50.00]; BAYES_HAM(-3.00)[99.99%]; MID_CONTAINS_FROM(1.00)[]; NEURAL_HAM_LONG(-1.00)[-1.000]; R_DKIM_ALLOW(-0.20)[suse.de:s=susede2_rsa,suse.de:s=susede2_ed25519]; NEURAL_HAM_SHORT(-0.20)[-1.000]; MIME_GOOD(-0.10)[text/plain]; MX_GOOD(-0.01)[]; TO_MATCH_ENVRCPT_ALL(0.00)[]; DKIM_SIGNED(0.00)[suse.de:s=susede2_rsa,suse.de:s=susede2_ed25519]; ARC_NA(0.00)[]; FUZZY_RATELIMITED(0.00)[rspamd.com]; MIME_TRACE(0.00)[0:+]; FROM_HAS_DN(0.00)[]; RCVD_TLS_ALL(0.00)[]; DKIM_TRACE(0.00)[suse.de:+]; RCVD_COUNT_TWO(0.00)[2]; FROM_EQ_ENVFROM(0.00)[]; TO_DN_SOME(0.00)[]; RCPT_COUNT_SEVEN(0.00)[7]; MISSING_XM_UA(0.00)[]; RCVD_VIA_SMTP_AUTH(0.00)[]; DBL_BLOCKED_OPENRESOLVER(0.00)[suse.de:mid,suse.de:dkim,suse.de:email] X-Spam-Flag: NO X-Spam-Level: X-Rspamd-Queue-Id: 779E41F78B X-Rspamd-Server: rspamd2.dmz-prg2.suse.org X-Rspamd-Action: no action X-Spam-Score: -3.51 On Mon, 6 Oct 2025 21:40:03 -0700, Christoph Hellwig wrote: > On Tue, Oct 07, 2025 at 12:55:03AM +0100, Dmitry Safonov via B4 Relay wrote: > > From: Dmitry Safonov > > > > Here at Arista gen_init_cpio is used in testing in order to create > > an initramfs for specific tests. Most notably, there is a test that does > > essentially a fork-bomb in kdump/panic kernel, replacing build-time > > generated init script: instead of doing makedumpfile, it does call > > shell tests. > > Why is is using fsync at all? Seems like this was added in > > commit ae18b94099b04264b32e33b057114024bc72c993 > Author: David Disseldorp > Date: Tue Aug 19 13:05:45 2025 +1000 > > gen_init_cpio: support -o parameter > > without any good explanation. In general doing a per-file fsync > is going to horrible wreck performance, and given that no one is > interested in partial initramfs archives also rather pointless. I should have explained why in the commit, sorry. The intention was to catch any FS I/O errors during output archive writeback. fsync() is called only once as the final I/O.