From: awilliam@xenbuild2.aw <awilliam@xenbuild2.aw>
Date: Thu, 11 Jan 2007 21:27:39 +0000 (-0700)
Subject: [IA64] Can't inject event, when guest is executing rfi
X-Git-Tag: archive/raspbian/4.8.0-1+rpi1~1^2~15413
X-Git-Url: https://dgit.raspbian.org/%22http:/www.example.com/cgi/%22https://%22%22/%22http:/www.example.com/cgi/%22https:/%22%22?a=commitdiff_plain;h=2293be461e7fbd877b44c565748b8cc2885117be;p=xen.git

[IA64] Can't inject event, when guest is executing rfi

Can't inject event, when guest is executing rfi, and both
both PSCB(v, ifs) and regs->ifs are valid

It's very rare case, but I did catch it.
It caused domain0 crash

Signed-off-by: Anthony Xu <anthony.xu@intel.com>
---

diff --git a/xen/arch/ia64/xen/faults.c b/xen/arch/ia64/xen/faults.c
index 8893c7395f..454bdd69a6 100644
--- a/xen/arch/ia64/xen/faults.c
+++ b/xen/arch/ia64/xen/faults.c
@@ -134,6 +134,11 @@ void reflect_event(struct pt_regs *regs)
 	if (!event_pending(v))
 		return;
 
+	// can't inject event, when XEN is emulating rfi 
+	// and both PSCB(v, ifs) and regs->ifs are valid
+	if (regs->cr_iip == *(unsigned long *)dorfirfi)
+		return;
+
 	if (!PSCB(v, interrupt_collection_enabled))
 		printk("psr.ic off, delivering event, ipsr=%lx,iip=%lx,"
 		       "isr=%lx,viip=0x%lx\n",
diff --git a/xen/arch/ia64/xen/vcpu.c b/xen/arch/ia64/xen/vcpu.c
index 8adad97c21..10a8227ef7 100644
--- a/xen/arch/ia64/xen/vcpu.c
+++ b/xen/arch/ia64/xen/vcpu.c
@@ -1326,7 +1326,6 @@ IA64FAULT vcpu_rfi(VCPU * vcpu)
 	u64 int_enable, regspsr = 0;
 	u64 ifs;
 	REGS *regs = vcpu_regs(vcpu);
-	extern void dorfirfi(void);
 
 	psr.i64 = PSCB(vcpu, ipsr);
 	if (psr.ia64_psr.cpl < 3)
@@ -1350,18 +1349,24 @@ IA64FAULT vcpu_rfi(VCPU * vcpu)
 		return IA64_ILLOP_FAULT;
 	}
 	PSCB(vcpu, incomplete_regframe) = 0;	// is this necessary?
+
 	ifs = PSCB(vcpu, ifs);
-	//if ((ifs & regs->cr_ifs & 0x8000000000000000L) && ifs != regs->cr_ifs) {
-	//if ((ifs & 0x8000000000000000L) && ifs != regs->cr_ifs) {
-	if (ifs & regs->cr_ifs & 0x8000000000000000L) {
-		// TODO: validate PSCB(vcpu,iip)
-		// TODO: PSCB(vcpu,ipsr) = psr;
-		PSCB(vcpu, ipsr) = psr.i64;
-		// now set up the trampoline
-		regs->cr_iip = *(unsigned long *)dorfirfi; // function pointer!!
-		__asm__ __volatile("mov %0=psr;;":"=r"(regspsr)::"memory");
-		regs->cr_ipsr =
-		    regspsr & ~(IA64_PSR_I | IA64_PSR_IC | IA64_PSR_BN);
+	if (ifs > 0x8000000000000000UL) {
+		if (regs->cr_ifs > 0x8000000000000000UL) {
+			// TODO: validate PSCB(vcpu,iip)
+			// TODO: PSCB(vcpu,ipsr) = psr;
+			PSCB(vcpu, ipsr) = psr.i64;
+			// now set up the trampoline
+			regs->cr_iip = *(unsigned long *)dorfirfi; // func ptr!
+			__asm__ __volatile("mov %0=psr;;":"=r"(regspsr)
+			                   ::"memory");
+			regs->cr_ipsr = regspsr & ~(IA64_PSR_I | IA64_PSR_IC |
+			                            IA64_PSR_BN);
+		} else {
+			regs->cr_ifs = ifs;
+			regs->cr_ipsr = psr.i64;
+			regs->cr_iip = PSCB(vcpu, iip);
+		}
 	} else {
 		regs->cr_ipsr = psr.i64;
 		regs->cr_iip = PSCB(vcpu, iip);
diff --git a/xen/include/asm-ia64/vcpu.h b/xen/include/asm-ia64/vcpu.h
index b61915e3b2..e403213d65 100644
--- a/xen/include/asm-ia64/vcpu.h
+++ b/xen/include/asm-ia64/vcpu.h
@@ -23,6 +23,8 @@ extern u64 cycle_to_ns(u64 cycle);
 
 #define SPURIOUS_VECTOR 0xf
 
+extern void dorfirfi(void);
+
 /* general registers */
 extern u64 vcpu_get_gr(VCPU * vcpu, unsigned long reg);
 extern IA64FAULT vcpu_get_gr_nat(VCPU * vcpu, unsigned long reg, u64 * val);