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-rw-r--r--system/xen/xsa/xsa223.patch54
1 files changed, 0 insertions, 54 deletions
diff --git a/system/xen/xsa/xsa223.patch b/system/xen/xsa/xsa223.patch
deleted file mode 100644
index 42f116b70c..0000000000
--- a/system/xen/xsa/xsa223.patch
+++ /dev/null
@@ -1,54 +0,0 @@
-From: Julien Grall <julien.grall@arm.com>
-Subject: arm: vgic: Don't update the LR when the IRQ is not enabled
-
-gic_raise_inflight_irq will be called if the IRQ is already inflight
-(i.e the IRQ is injected to the guest). If the IRQ is already already in
-the LRs, then the associated LR will be updated.
-
-To know if the interrupt is already in the LR, the function check if the
-interrupt is queued. However, if the interrupt is not enabled then the
-interrupt may not be queued nor in the LR. So gic_update_one_lr may be
-called (if we inject on the current vCPU) and read the LR.
-
-Because the interrupt is not in the LR, Xen will either read:
- * LR 0 if the interrupt was never injected before
- * LR 255 (GIC_INVALID_LR) if the interrupt was injected once. This
- is because gic_update_one_lr will reset p->lr.
-
-Reading LR 0 will result to potentially update the wrong interrupt and
-not keep the LRs in sync with Xen.
-
-Reading LR 255 will result to:
- * Crash Xen on GICv3 as the LR index is bigger than supported (see
- gicv3_ich_read_lr).
- * Read/write always GICH_LR + 255 * 4 that is not part of the memory
- mapped.
-
-The problem can be prevented by checking whether the interrupt is
-enabled in gic_raise_inflight_irq before calling gic_update_one_lr.
-
-A follow-up of this patch is expected to mitigate the issue in the
-future.
-
-This is XSA-223.
-
-Reported-by: Julien Grall <julien.grall@arm.com>
-Signed-off-by: Julien Grall <julien.grall@arm.com>
-Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
----
- xen/arch/arm/gic.c | 4 ++++
- 1 file changed, 4 insertions(+)
-
---- a/xen/arch/arm/gic.c
-+++ b/xen/arch/arm/gic.c
-@@ -417,6 +417,10 @@ void gic_raise_inflight_irq(struct vcpu *v, unsigned int virtual_irq)
-
- ASSERT(spin_is_locked(&v->arch.vgic.lock));
-
-+ /* Don't try to update the LR if the interrupt is disabled */
-+ if ( !test_bit(GIC_IRQ_GUEST_ENABLED, &n->status) )
-+ return;
-+
- if ( list_empty(&n->lr_queue) )
- {
- if ( v == current )