commit 843e64492a7ed11436cc5c9bbfba46835939071a Author: Greg Kroah-Hartman Date: Fri Jan 10 14:31:36 2025 +0100 Linux 6.6.71 Signed-off-by: Greg Kroah-Hartman commit a6923798e471570ac1b24086be0a9679f51c3171 Author: Naman Jain Date: Tue Sep 17 11:09:17 2024 +0530 x86/hyperv: Fix hv tsc page based sched_clock for hibernation commit bcc80dec91ee745b3d66f3e48f0ec2efdea97149 upstream. read_hv_sched_clock_tsc() assumes that the Hyper-V clock counter is bigger than the variable hv_sched_clock_offset, which is cached during early boot, but depending on the timing this assumption may be false when a hibernated VM starts again (the clock counter starts from 0 again) and is resuming back (Note: hv_init_tsc_clocksource() is not called during hibernation/resume); consequently, read_hv_sched_clock_tsc() may return a negative integer (which is interpreted as a huge positive integer since the return type is u64) and new kernel messages are prefixed with huge timestamps before read_hv_sched_clock_tsc() grows big enough (which typically takes several seconds). Fix the issue by saving the Hyper-V clock counter just before the suspend, and using it to correct the hv_sched_clock_offset in resume. This makes hv tsc page based sched_clock continuous and ensures that post resume, it starts from where it left off during suspend. Override x86_platform.save_sched_clock_state and x86_platform.restore_sched_clock_state routines to correct this as soon as possible. Note: if Invariant TSC is available, the issue doesn't happen because 1) we don't register read_hv_sched_clock_tsc() for sched clock: See commit e5313f1c5404 ("clocksource/drivers/hyper-v: Rework clocksource and sched clock setup"); 2) the common x86 code adjusts TSC similarly: see __restore_processor_state() -> tsc_verify_tsc_adjust(true) and x86_platform.restore_sched_clock_state(). Cc: stable@vger.kernel.org Fixes: 1349401ff1aa ("clocksource/drivers/hyper-v: Suspend/resume Hyper-V clocksource for hibernation") Co-developed-by: Dexuan Cui Signed-off-by: Dexuan Cui Signed-off-by: Naman Jain Reviewed-by: Michael Kelley Link: https://lore.kernel.org/r/20240917053917.76787-1-namjain@linux.microsoft.com Signed-off-by: Wei Liu Message-ID: <20240917053917.76787-1-namjain@linux.microsoft.com> Signed-off-by: Greg Kroah-Hartman commit b34e805539dabbebfa6030842f4a0ba14de8f813 Author: Greg Kroah-Hartman Date: Fri Jan 10 13:09:11 2025 +0100 Revert "x86, crash: wrap crash dumping code into crash related ifdefs" This reverts commit e5b1574a8ca28c40cf53eda43f6c3b016ed41e27 which is commit a4eeb2176d89fdf2785851521577b94b31690a60 upstream. When this change is backported to the 6.6.y tree, it can cause build errors on some configurations when KEXEC is not enabled, so revert it for now. Reported-by: Ignat Korchagin Link: https://lore.kernel.org/r/3DB3A6D3-0D3A-4682-B4FA-407B2D3263B2@cloudflare.com Reported-by: Lars Wendler Link: https://lore.kernel.org/r/20250110103328.0e3906a8@chagall.paradoxon.rec Reported-by: Chris Clayton Link: https://lore.kernel.org/r/10c7be00-b1f8-4389-801b-fb2d0b22468d@googlemail.com Cc: Al Viro Cc: Andrew Morton Cc: Dexuan Cui Cc: Eric W. Biederman Cc: Hari Bathini Cc: Klara Modin Cc: Michael Kelley Cc: Michael Kelley Cc: Naman Jain Cc: Nathan Chancellor Cc: Pingfan Liu Cc: Sasha Levin Cc: Stephen Rothwell Cc: Wei Liu Cc: Yang Li Signed-off-by: Greg Kroah-Hartman commit c8bc44c5f96172fdaab66a268a53dccc6c7ffa87 Author: Greg Kroah-Hartman Date: Fri Jan 10 13:06:34 2025 +0100 Revert "x86/hyperv: Fix hv tsc page based sched_clock for hibernation" This reverts commit 6681113633dc738ec95fe33104843a1e25acef3b which is commit bcc80dec91ee745b3d66f3e48f0ec2efdea97149 upstream. The dependant patch before this one caused build errors in the 6.6.y tree, so revert this for now so that we can fix them up properly. Reported-by: Ignat Korchagin Link: https://lore.kernel.org/r/3DB3A6D3-0D3A-4682-B4FA-407B2D3263B2@cloudflare.com Reported-by: Lars Wendler Link: https://lore.kernel.org/r/20250110103328.0e3906a8@chagall.paradoxon.rec Reported-by: Chris Clayton Link: https://lore.kernel.org/r/10c7be00-b1f8-4389-801b-fb2d0b22468d@googlemail.com Cc: Dexuan Cui Cc: Naman Jain Cc: Michael Kelley Cc: Wei Liu Cc: Sasha Levin Signed-off-by: Greg Kroah-Hartman