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charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-Spamd-Result: default: False [-4.51 / 50.00]; BAYES_HAM(-3.00)[100.00%]; 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)[]; FUZZY_RATELIMITED(0.00)[rspamd.com]; RCVD_VIA_SMTP_AUTH(0.00)[]; ARC_NA(0.00)[]; RCPT_COUNT_SEVEN(0.00)[9]; MIME_TRACE(0.00)[0:+]; MID_RHS_MATCH_FROM(0.00)[]; RCVD_TLS_ALL(0.00)[]; DKIM_SIGNED(0.00)[suse.de:s=susede2_rsa,suse.de:s=susede2_ed25519]; FROM_EQ_ENVFROM(0.00)[]; FROM_HAS_DN(0.00)[]; TO_DN_SOME(0.00)[]; RCVD_COUNT_TWO(0.00)[2]; TO_MATCH_ENVRCPT_ALL(0.00)[]; DBL_BLOCKED_OPENRESOLVER(0.00)[suse.de:mid,suse.de:dkim,suse.de:email]; DKIM_TRACE(0.00)[suse.de:+] X-Spam-Flag: NO X-Spam-Level: X-Rspamd-Queue-Id: C181C1F441 X-Rspamd-Server: rspamd2.dmz-prg2.suse.org X-Rspamd-Action: no action X-Spam-Score: -4.51 On 8/4/25 16:08, Keith Busch wrote: > On Mon, Aug 04, 2025 at 08:54:00AM +0200, Hannes Reinecke wrote: >> On 8/2/25 01:47, Keith Busch wrote: >>> +static int bio_align_to_lbs(struct bio *bio, struct iov_iter *iter) >>> +{ >>> + struct block_device *bdev = bio->bi_bdev; >>> + size_t nbytes; >>> + >>> + if (!bdev) >>> + return 0; >>> + >>> + nbytes = bio->bi_iter.bi_size & (bdev_logical_block_size(bdev) - 1); >>> + if (!nbytes) >>> + return 0; >>> + >>> + bio_revert(bio, nbytes); >>> + iov_iter_revert(iter, nbytes); >>> + if (!bio->bi_iter.bi_size) >>> + return -EFAULT; >>> + >>> + return 0; >>> +} >>> + >>> /** >>> * bio_iov_iter_get_pages - add user or kernel pages to a bio >>> * @bio: bio to add pages to >>> @@ -1336,6 +1355,7 @@ int bio_iov_iter_get_pages(struct bio *bio, struct iov_iter *iter) >>> ret = __bio_iov_iter_get_pages(bio, iter); >>> } while (!ret && iov_iter_count(iter) && !bio_full(bio, 0)); >>> + ret = bio_align_to_lbs(bio, iter); >>> return bio->bi_vcnt ? 0 : ret; >> >> Wouldn't that cause the error from bio_align_to_lba() to be ignored >> if bio->bi_vcnt is greater than 0? > > That returns an error only if the alignment reduces the size to 0, so > there would be a bug somewhere if bi_vcnt is not also 0 in that case. It would, but we wouldn't be seeing it as 'ret' would be obscured if 'bio->bi_vcnt' continues to be greater than zero and 'ret' is set. Cheers, Hannes -- Dr. Hannes Reinecke Kernel Storage Architect hare@suse.de +49 911 74053 688 SUSE Software Solutions GmbH, Frankenstr. 146, 90461 Nürnberg HRB 36809 (AG Nürnberg), GF: I. Totev, A. McDonald, W. Knoblich