Merge release-20200127.0-85-g1b6a12a (automated)

4 files changed, 5 insertions, 3 deletions

diff --git a/pkg/sentry/arch/arch_aarch64_state_autogen.go b/pkg/sentry/arch/arch_aarch64_state_autogen.go
index 3e0685928..9c6dfdf2e 100755
--- a/pkg/sentry/arch/arch_aarch64_state_autogen.go
+++ b/pkg/sentry/arch/arch_aarch64_state_autogen.go
@@ -4,4 +4,3 @@
 // +build arm64
 
 package arch
-
diff --git a/pkg/sentry/arch/arch_arm64_state_autogen.go b/pkg/sentry/arch/arch_arm64_state_autogen.go
index 4d56ebcca..49f2e3d67 100755
--- a/pkg/sentry/arch/arch_arm64_state_autogen.go
+++ b/pkg/sentry/arch/arch_arm64_state_autogen.go
@@ -3,4 +3,3 @@
 // +build arm64
 
 package arch
-
diff --git a/pkg/sentry/arch/arch_x86.go b/pkg/sentry/arch/arch_x86.go
index a18093155..3db8bd34b 100644
--- a/pkg/sentry/arch/arch_x86.go
+++ b/pkg/sentry/arch/arch_x86.go
@@ -114,6 +114,10 @@ func newX86FPStateSlice() []byte {
 	size, align := cpuid.HostFeatureSet().ExtendedStateSize()
 	capacity := size
 	// Always use at least 4096 bytes.
+	//
+	// For the KVM platform, this state is a fixed 4096 bytes, so make sure
+	// that the underlying array is at _least_ that size otherwise we will
+	// corrupt random memory. This is not a pleasant thing to debug.
 	if capacity < 4096 {
 		capacity = 4096
 	}
diff --git a/pkg/sentry/arch/signal_amd64.go b/pkg/sentry/arch/signal_amd64.go
index 81b92bb43..6fb756f0e 100644
--- a/pkg/sentry/arch/signal_amd64.go
+++ b/pkg/sentry/arch/signal_amd64.go
@@ -55,7 +55,7 @@ type SignalContext64 struct {
 	Trapno  uint64
 	Oldmask linux.SignalSet
 	Cr2     uint64
-	// Pointer to a struct _fpstate.
+	// Pointer to a struct _fpstate. See b/33003106#comment8.
 	Fpstate  uint64
 	Reserved [8]uint64
 }