diff options
| author | Brian Norris <[email protected]> | 2025-06-12 18:32:52 +0000 |
|---|---|---|
| committer | Thomas Gleixner <[email protected]> | 2025-06-13 13:13:35 +0000 |
| commit | 72218d74c9c57b8ea36c2a58875dff406fc10462 (patch) | |
| tree | 982e97296adcd1d83f85a535ade024dd2df965ec /rust/helpers/helpers.c | |
| parent | genirq/cpuhotplug: Rebalance managed interrupts across multi-CPU hotplug (diff) | |
| download | kernel-72218d74c9c57b8ea36c2a58875dff406fc10462.tar.gz kernel-72218d74c9c57b8ea36c2a58875dff406fc10462.zip | |
genirq/cpuhotplug: Restore affinity even for suspended IRQ
Commit 788019eb559f ("genirq: Retain disable depth for managed interrupts
across CPU hotplug") tried to make managed shutdown/startup properly
reference counted, but it missed the fact that the unplug and hotplug code
has an intentional imbalance by skipping IRQS_SUSPENDED interrupts on
the "restore" path.
This means that if a managed-affinity interrupt was both suspended and
managed-shutdown (such as may happen during system suspend / S3), resume
skips calling irq_startup_managed(), and would again have an unbalanced
depth this time, with a positive value (i.e., remaining unexpectedly
masked).
This IRQS_SUSPENDED check was introduced in commit a60dd06af674
("genirq/cpuhotplug: Skip suspended interrupts when restoring affinity")
for essentially the same reason as commit 788019eb559f, to prevent that
irq_startup() would unconditionally re-enable an interrupt too early.
Because irq_startup_managed() now respsects the disable-depth count, the
IRQS_SUSPENDED check is not longer needed, and instead, it causes harm.
Thus, drop the IRQS_SUSPENDED check, and restore balance.
This effectively reverts commit a60dd06af674 ("genirq/cpuhotplug: Skip
suspended interrupts when restoring affinity"), because it is replaced
by commit 788019eb559f ("genirq: Retain disable depth for managed
interrupts across CPU hotplug").
Fixes: 788019eb559f ("genirq: Retain disable depth for managed interrupts across CPU hotplug")
Reported-by: Aleksandrs Vinarskis <[email protected]>
Signed-off-by: Brian Norris <[email protected]>
Signed-off-by: Thomas Gleixner <[email protected]>
Tested-by: Aleksandrs Vinarskis <[email protected]>
Link: https://lore.kernel.org/all/[email protected]
Closes: https://lore.kernel.org/lkml/[email protected]/
Diffstat (limited to 'rust/helpers/helpers.c')
0 files changed, 0 insertions, 0 deletions
