On Sat, 2025-03-29 at 10:04 -0400, James Bottomley wrote: > On Sat, 2025-03-29 at 09:42 +0100, Christian Brauner wrote: > > Add the necessary infrastructure changes to support freezing for > > suspend and hibernate. > > > > Just got back from LSFMM. So still jetlagged and likelihood of bugs > > increased. This should all that's needed to wire up power. > > > > This will be in vfs-6.16.super shortly. > > > > --- > > Changes in v2: > > - Don't grab reference in the iterator make that a requirement for > > the callers that need custom behavior. > > - Link to v1: > > https://lore.kernel.org/r/20250328-work-freeze-v1-0-a2c3a6b0e7a6@xxxxxxxxxx > > Given I've been a bit quiet on this, I thought I'd better explain > what's going on: I do have these built, but I made the mistake of > doing a dist-upgrade on my testing VM master image and it pulled in a > version of systemd (257.4-3) that has a broken hibernate. Since I > upgraded in place I don't have the old image so I'm spending my time > currently debugging systemd ... normal service will hopefully resume > shortly. I found the systemd bug https://github.com/systemd/systemd/issues/36888 And hacked around it, so I can confirm a simple hibernate/resume works provided the sd_start_write() patches are applied (and the hooks are plumbed in to pm). There is an oddity: the systemd-journald process that would usually hang hibernate in D wait goes into R but seems to be hung and can't be killed by the watchdog even with a -9. It's stack trace says it's still stuck in sb_start_write: [<0>] percpu_rwsem_wait.constprop.10+0xd1/0x140 [<0>] ext4_page_mkwrite+0x3c1/0x560 [ext4] [<0>] do_page_mkwrite+0x38/0xa0 [<0>] do_wp_page+0xd5/0xba0 [<0>] __handle_mm_fault+0xa29/0xca0 [<0>] handle_mm_fault+0x16a/0x2d0 [<0>] do_user_addr_fault+0x3ab/0x810 [<0>] exc_page_fault+0x68/0x150 [<0>] asm_exc_page_fault+0x22/0x30 So I think there's something funny going on in thaw. Regards, James
