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authorJakub Kicinski <kuba@kernel.org>2024-11-14 11:27:36 -0800
committerJakub Kicinski <kuba@kernel.org>2024-11-14 11:29:15 -0800
commita79993b5fce69e97f900bb975f6127e25cebf130 (patch)
treef73ec541ca4183893a0bdc3d30f779c6999a0d9a /arch/x86/kvm/lapic.c
parenteth: fbnic: Add support to dump registers (diff)
parentMerge tag 'net-6.12-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/net... (diff)
downloadlinux-a79993b5fce69e97f900bb975f6127e25cebf130.tar.gz
linux-a79993b5fce69e97f900bb975f6127e25cebf130.zip
Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Cross-merge networking fixes after downstream PR (net-6.12-rc8). Conflicts: tools/testing/selftests/net/.gitignore 252e01e68241 ("selftests: net: add netlink-dumps to .gitignore") be43a6b23829 ("selftests: ncdevmem: Move ncdevmem under drivers/net/hw") https://lore.kernel.org/all/20241113122359.1b95180a@canb.auug.org.au/ drivers/net/phy/phylink.c 671154f174e0 ("net: phylink: ensure PHY momentary link-fails are handled") 7530ea26c810 ("net: phylink: remove "using_mac_select_pcs"") Adjacent changes: drivers/net/ethernet/stmicro/stmmac/dwmac-intel-plat.c 5b366eae7193 ("stmmac: dwmac-intel-plat: fix call balance of tx_clk handling routines") e96321fad3ad ("net: ethernet: Switch back to struct platform_driver::remove()") Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'arch/x86/kvm/lapic.c')
-rw-r--r--arch/x86/kvm/lapic.c29
1 files changed, 18 insertions, 11 deletions
diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
index 2098dc689088..95c6beb8ce27 100644
--- a/arch/x86/kvm/lapic.c
+++ b/arch/x86/kvm/lapic.c
@@ -2629,19 +2629,26 @@ void kvm_apic_update_apicv(struct kvm_vcpu *vcpu)
{
struct kvm_lapic *apic = vcpu->arch.apic;
- if (apic->apicv_active) {
- /* irr_pending is always true when apicv is activated. */
- apic->irr_pending = true;
+ /*
+ * When APICv is enabled, KVM must always search the IRR for a pending
+ * IRQ, as other vCPUs and devices can set IRR bits even if the vCPU
+ * isn't running. If APICv is disabled, KVM _should_ search the IRR
+ * for a pending IRQ. But KVM currently doesn't ensure *all* hardware,
+ * e.g. CPUs and IOMMUs, has seen the change in state, i.e. searching
+ * the IRR at this time could race with IRQ delivery from hardware that
+ * still sees APICv as being enabled.
+ *
+ * FIXME: Ensure other vCPUs and devices observe the change in APICv
+ * state prior to updating KVM's metadata caches, so that KVM
+ * can safely search the IRR and set irr_pending accordingly.
+ */
+ apic->irr_pending = true;
+
+ if (apic->apicv_active)
apic->isr_count = 1;
- } else {
- /*
- * Don't clear irr_pending, searching the IRR can race with
- * updates from the CPU as APICv is still active from hardware's
- * perspective. The flag will be cleared as appropriate when
- * KVM injects the interrupt.
- */
+ else
apic->isr_count = count_vectors(apic->regs + APIC_ISR);
- }
+
apic->highest_isr_cache = -1;
}