Messages in this thread | | | Subject | Re: [PATCH] iommu/vt-d: Fix an unbalanced rcu_read_lock/rcu_read_unlock() | From | Lu Baolu <> | Date | Mon, 8 Nov 2021 10:18:17 +0800 |
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On 11/7/21 12:53 AM, Christophe JAILLET wrote: > If we return -EOPNOTSUPP, the rcu lock remains lock. This is spurious. > Go through the end of the function instead. This way, the missing > 'rcu_read_unlock()' is called. > > Fixes: 7afd7f6aa21a ("iommu/vt-d: Check FL and SL capability sanity in scalable mode") > Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr> > --- > This patch is speculative, review with care. > --- > drivers/iommu/intel/cap_audit.c | 5 +++-- > 1 file changed, 3 insertions(+), 2 deletions(-) > > diff --git a/drivers/iommu/intel/cap_audit.c b/drivers/iommu/intel/cap_audit.c > index b39d223926a4..71596fc62822 100644 > --- a/drivers/iommu/intel/cap_audit.c > +++ b/drivers/iommu/intel/cap_audit.c > @@ -144,6 +144,7 @@ static int cap_audit_static(struct intel_iommu *iommu, enum cap_audit_type type) > { > struct dmar_drhd_unit *d; > struct intel_iommu *i; > + int rc = 0; > > rcu_read_lock(); > if (list_empty(&dmar_drhd_units)) > @@ -169,11 +170,11 @@ static int cap_audit_static(struct intel_iommu *iommu, enum cap_audit_type type) > */ > if (intel_cap_smts_sanity() && > !intel_cap_flts_sanity() && !intel_cap_slts_sanity()) > - return -EOPNOTSUPP; > + rc = -EOPNOTSUPP; > > out: > rcu_read_unlock(); > - return 0; > + return rc; > } > > int intel_cap_audit(enum cap_audit_type type, struct intel_iommu *iommu) >
Nice catch! Thank you!
I will queue this for v5.16.
Best regards, baolu
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