[TLDR: I'm adding this report to the list of tracked Linux kernel regressions; the text you find below is based on a few templates paragraphs you might have encountered already in similar form. See link in footer if these mails annoy you.] On 03.08.23 10:27, Vlastimil Babka wrote: > On 5/31/23 14:55, Christoph Hellwig wrote: >> software_resume can be called either from an init call in the boot code, >> or from sysfs once the system has finished booting, and the two >> invocation methods this can't race with each other. >> >> For the latter case we did just parse the suspend device manually, while >> the former might not have one. Split software_resume so that the search >> only happens for the boot case, which also means the special lockdep >> nesting annotation can go away as the system transition mutex can be >> taken a little later and doesn't have the sysfs locking nest inside it. >> >> Signed-off-by: Christoph Hellwig <hch@xxxxxx> >> Acked-by: Rafael J. Wysocki <rafael@xxxxxxxxxx> > > This caused a regression for me in 6.5-rc1+, fix below. > > ----8<---- >>From 95a310ae6cfae9b3cab61e54a1bce488c3ab93a1 Mon Sep 17 00:00:00 2001 > From: Vlastimil Babka <vbabka@xxxxxxx> > Date: Wed, 2 Aug 2023 15:46:18 +0200 > Subject: [PATCH] PM: hibernate: fix resume_store() return value when > hibernation not available > > On a laptop with hibernation set up but not actively used, and with > secure boot and lockdown enabled kernel, 6.5-rc1 gets stuck on boot with > the following repeated messages: > > A start job is running for Resume from hibernation using device /dev/system/swap (24s / no limit) > lockdown_is_locked_down: 25311154 callbacks suppressed > Lockdown: systemd-hiberna: hibernation is restricted; see man kernel_lockdown.7 > ... > > Checking the resume code leads to commit cc89c63e2fe3 ("PM: hibernate: > move finding the resume device out of software_resume") which > inadvertently changed the return value from resume_store() to 0 when > !hibernation_available(). This apparently translates to userspace > write() returning 0 as in number of bytes written, and userspace looping > indefinitely in the attempt to write the intended value. > > Fix this by returning the full number of bytes that were to be written, > as that's what was done before the commit. > > Fixes: cc89c63e2fe3 ("PM: hibernate: move finding the resume device out of software_resume") > [...] Thanks for the report. To be sure the issue doesn't fall through the cracks unnoticed, I'm adding it to regzbot, the Linux kernel regression tracking bot: #regzbot ^introduced cc89c63e2fe3 #regzbot title pm: boot problems when hibernate is configured and kernel locked down #regzbot fix: PM: hibernate: fix resume_store() return value when hibernation not available #regzbot ignore-activity This isn't a regression? This issue or a fix for it are already discussed somewhere else? It was fixed already? You want to clarify when the regression started to happen? Or point out I got the title or something else totally wrong? Then just reply and tell me -- ideally while also telling regzbot about it, as explained by the page listed in the footer of this mail. Developers: When fixing the issue, remember to add 'Link:' tags pointing to the report (the parent of this mail). See page linked in footer for details. Ciao, Thorsten (wearing his 'the Linux kernel's regression tracker' hat) -- Everything you wanna know about Linux kernel regression tracking: https://linux-regtracking.leemhuis.info/about/#tldr That page also explains what to do if mails like this annoy you. -- dm-devel mailing list dm-devel@xxxxxxxxxx https://listman.redhat.com/mailman/listinfo/dm-devel