genirq/msi: Take the per-device MSI lock before validating the control structure
Calling msi_ctrl_valid() ultimately results in calling
msi_get_device_domain(), which requires holding the device MSI lock.
However, we take that lock right after having called msi_ctrl_valid(),
which is just a tad too late. Taking the lock earlier solves the issue.
Fixes: 40742716f294 ("genirq/msi: Make msi_add_simple_msi_descs() device domain aware")
Reported-by: "Russell King (Oracle)" <linux@armlinux.org.uk>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/Y/Opu6ETe3ZzZ/8E@shell.armlinux.org.uk
diff --git a/kernel/irq/msi.c b/kernel/irq/msi.c
index 783a3e6..13d9649 100644
--- a/kernel/irq/msi.c
+++ b/kernel/irq/msi.c
@@ -1084,10 +1084,13 @@
struct xarray *xa;
int ret, virq;
- if (!msi_ctrl_valid(dev, &ctrl))
- return -EINVAL;
-
msi_lock_descs(dev);
+
+ if (!msi_ctrl_valid(dev, &ctrl)) {
+ ret = -EINVAL;
+ goto unlock;
+ }
+
ret = msi_domain_add_simple_msi_descs(dev, &ctrl);
if (ret)
goto unlock;
