From b58fb6e81bd55b6bd946abc3070770f7994c9ef9 Mon Sep 17 00:00:00 2001 From: Jason Andryuk Date: Tue, 7 Jun 2022 13:55:39 +0200 Subject: [PATCH 02/51] x86/irq: skip unmap_domain_pirq XSM during destruction MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit xsm_unmap_domain_irq was seen denying unmap_domain_pirq when called from complete_domain_destroy as an RCU callback. The source context was an unexpected, random domain. Since this is a xen-internal operation, going through the XSM hook is inapproriate. Check d->is_dying and skip the XSM hook when set since this is a cleanup operation for a domain being destroyed. Suggested-by: Roger Pau Monné Signed-off-by: Jason Andryuk Reviewed-by: Jan Beulich Reviewed-by: Roger Pau Monné master commit: 2e6f95a942d1927a53f077c301db0b799c54c05a master date: 2022-04-08 14:51:52 +0200 --- xen/arch/x86/irq.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) diff --git a/xen/arch/x86/irq.c b/xen/arch/x86/irq.c index 67cbf6b979dc..47b86af5dce9 100644 --- a/xen/arch/x86/irq.c +++ b/xen/arch/x86/irq.c @@ -2342,8 +2342,14 @@ int unmap_domain_pirq(struct domain *d, int pirq) nr = msi_desc->msi.nvec; } - ret = xsm_unmap_domain_irq(XSM_HOOK, d, irq, - msi_desc ? msi_desc->dev : NULL); + /* + * When called by complete_domain_destroy via RCU, current is a random + * domain. Skip the XSM check since this is a Xen-initiated action. + */ + if ( !d->is_dying ) + ret = xsm_unmap_domain_irq(XSM_HOOK, d, irq, + msi_desc ? msi_desc->dev : NULL); + if ( ret ) goto done; -- 2.35.1