Thomas Gleixner 53f408cad0 hrtimers: Push pending hrtimers away from outgoing CPU earlier ... [ Upstream commit 5c0930ccaa ] 2b8272ff4a ("cpu/hotplug: Prevent self deadlock on CPU hot-unplug") solved the straight forward CPU hotplug deadlock vs. the scheduler bandwidth timer. Yu discovered a more involved variant where a task which has a bandwidth timer started on the outgoing CPU holds a lock and then gets throttled. If the lock required by one of the CPU hotplug callbacks the hotplug operation deadlocks because the unthrottling timer event is not handled on the dying CPU and can only be recovered once the control CPU reaches the hotplug state which pulls the pending hrtimers from the dead CPU. Solve this by pushing the hrtimers away from the dying CPU in the dying callbacks. Nothing can queue a hrtimer on the dying CPU at that point because all other CPUs spin in stop_machine() with interrupts disabled and once the operation is finished the CPU is marked offline. Reported-by: Yu Liao <liaoyu15@huawei.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Liu Tie <liutie4@huawei.com> Link: https://lore.kernel.org/r/87a5rphara.ffs@tglx Signed-off-by: Sasha Levin <sashal@kernel.org>		2023-12-13 18:44:56 +01:00
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acpi	ACPI: PM: Add acpi_device_fix_up_power_children() function	2023-12-03 07:33:07 +01:00
asm-generic	hyperv-fixes for v6.6-rc6	2023-10-10 11:01:21 -07:00
clocksource
crypto
drm	drm: bridge: samsung-dsim: Fix waiting for empty cmd transfer FIFO on older Exynos	2023-11-20 11:59:08 +01:00
dt-bindings
keys
kunit
kvm	KVM: arm64: timers: Correctly handle TGE flip with CNTPOFF_EL2	2023-10-12 16:55:21 +01:00
linux	hrtimers: Push pending hrtimers away from outgoing CPU earlier	2023-12-13 18:44:56 +01:00
math-emu
media	media: ipu-bridge: increase sensor_name size	2023-11-28 17:19:46 +00:00
memory
misc
net	bpf, sockmap: af_unix stream sockets need to hold ref for pair sock	2023-12-08 08:52:23 +01:00
pcmcia
ras
rdma
rv
scsi	scsi: sd: Fix system start for ATA devices	2023-12-08 08:52:17 +01:00
soc	firmware: tegra: Add suspend hook and reset BPMP IPC early on resume	2023-11-20 11:59:16 +01:00
sound	ASoC: soc-dai: add flag to mute and unmute stream during trigger	2023-11-28 17:20:04 +00:00
target
trace	rxrpc: Fix RTT determination to use any ACK as a source	2023-12-03 07:33:02 +01:00
uapi	uapi: propagate __struct_group() attributes to the container union	2023-12-08 08:52:22 +01:00
ufs
vdso
video	fbdev: stifb: Make the STI next font pointer a 32-bit signed offset	2023-11-28 17:19:58 +00:00
xen	arm/xen: remove lazy mode related definitions	2023-09-19 07:04:49 +02:00