[PATCH] powerpc/icp-opal: Fix missing KVM case and harden replay
flat view
STALE3575d
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Date: 2017-01-16 02:19:34
Subsystem:
linux for powerpc (32-bit and 64-bit), the rest · Maintainers:
Madhavan Srinivasan, Linus Torvalds
The icp-opal call is missing the code from icp-native to recover
interrupts snatched by KVM. Without that, when running KVM, we can
get into a situation where an interrupt is lost and the CPU stuck
with an elevated CPPR.
Also harden replay by always checking the return from opal_int_eoi
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
---
arch/powerpc/sysdev/xics/icp-opal.c | 31 ++++++++++++++++++++++++-------
1 file changed, 24 insertions(+), 7 deletions(-)
diff --git a/arch/powerpc/sysdev/xics/icp-opal.c b/arch/powerpc/sysdev/xics/icp-opal.c
index d38e86f..60c5765 100644
--- a/arch/powerpc/sysdev/xics/icp-opal.c
+++ b/arch/powerpc/sysdev/xics/icp-opal.c@@ -20,6 +20,7 @@ #include #include #include +#include static void icp_opal_teardown_cpu(void) {
@@ -39,7 +40,26 @@ static void icp_opal_flush_ipi(void) * Should we be flagging idle loop instead? * Or creating some task to be scheduled? */ - opal_int_eoi((0x00 << 24) | XICS_IPI); + if (opal_int_eoi((0x00 << 24) | XICS_IPI) > 0) + force_external_irq_replay(); +} + +static unsigned int icp_opal_get_xirr(void) +{ + unsigned int kvm_xirr; + __be32 hw_xirr; + int64_t rc; + + /* Handle an interrupt latched by KVM first */ + kvm_xirr = kvmppc_get_xics_latch(); + if (kvm_xirr) + return kvm_xirr; + + /* Then ask OPAL */ + rc = opal_int_get_xirr(&hw_xirr, false); + if (rc < 0) + return 0; + return be32_to_cpu(hw_xirr); } static unsigned int icp_opal_get_irq(void)
@@ -47,12 +67,8 @@ static unsigned int icp_opal_get_irq(void) unsigned int xirr; unsigned int vec; unsigned int irq; - int64_t rc; - rc = opal_int_get_xirr(&xirr, false); - if (rc < 0) - return 0; - xirr = be32_to_cpu(xirr); + xirr = icp_opal_get_xirr(); vec = xirr & 0x00ffffff; if (vec == XICS_IRQ_SPURIOUS) return 0;
@@ -67,7 +83,8 @@ static unsigned int icp_opal_get_irq(void) xics_mask_unknown_vec(vec); /* We might learn about it later, so EOI it */ - opal_int_eoi(xirr); + if (opal_int_eoi(xirr) > 0) + force_external_irq_replay(); return 0; }