diff options
| author | Cédric Le Goater <clg@kaod.org> | 2021-10-11 09:02:03 +0200 |
|---|---|---|
| committer | Michael Ellerman <mpe@ellerman.id.au> | 2021-10-13 16:38:55 +1100 |
| commit | 6f779e1d359b8d5801f677c1d49dcfa10bf95674 (patch) | |
| tree | 4a3247e3bfeede1ca1779ba4e00daedc17e8071e /arch | |
| parent | eb8257a12192f43ffd41bd90932c39dade958042 (diff) | |
powerpc/xive: Discard disabled interrupts in get_irqchip_state()
When an interrupt is passed through, the KVM XIVE device calls the
set_vcpu_affinity() handler which raises the P bit to mask the
interrupt and to catch any in-flight interrupts while routing the
interrupt to the guest.
On the guest side, drivers (like some Intels) can request at probe
time some MSIs and call synchronize_irq() to check that there are no
in flight interrupts. This will call the XIVE get_irqchip_state()
handler which will always return true as the interrupt P bit has been
set on the host side and lock the CPU in an infinite loop.
Fix that by discarding disabled interrupts in get_irqchip_state().
Fixes: da15c03b047d ("powerpc/xive: Implement get_irqchip_state method for XIVE to fix shutdown race")
Cc: stable@vger.kernel.org #v5.4+
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Tested-by: seeteena <s1seetee@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20211011070203.99726-1-clg@kaod.org
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/powerpc/sysdev/xive/common.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/arch/powerpc/sysdev/xive/common.c b/arch/powerpc/sysdev/xive/common.c index c732ce5a3e1a..c5d75c02ad8b 100644 --- a/arch/powerpc/sysdev/xive/common.c +++ b/arch/powerpc/sysdev/xive/common.c @@ -945,7 +945,8 @@ static int xive_get_irqchip_state(struct irq_data *data, * interrupt to be inactive in that case. */ *state = (pq != XIVE_ESB_INVALID) && !xd->stale_p && - (xd->saved_p || !!(pq & XIVE_ESB_VAL_P)); + (xd->saved_p || (!!(pq & XIVE_ESB_VAL_P) && + !irqd_irq_disabled(data))); return 0; default: return -EINVAL; |