From 32ab382c80306d7dab499e983af2bfaea7770d1d Mon Sep 17 00:00:00 2001
From: Fabricio Voznika <fvoznika@google.com>
Date: Mon, 18 May 2020 10:21:43 -0700
Subject: [PATCH] Improve unsupported syscall message

PiperOrigin-RevId: 312104899
---
 runsc/boot/compat.go              |  8 +++++++-
 runsc/boot/compat_amd64.go        | 22 +++++++++++++---------
 runsc/boot/compat_arm64.go        | 22 +++++++++++++---------
 runsc/container/container_test.go |  2 +-
 4 files changed, 34 insertions(+), 20 deletions(-)

diff --git a/runsc/boot/compat.go b/runsc/boot/compat.go
index b7cfb35bf..84c67cbc2 100644
--- a/runsc/boot/compat.go
+++ b/runsc/boot/compat.go
@@ -119,7 +119,13 @@ func (c *compatEmitter) emitUnimplementedSyscall(us *spb.UnimplementedSyscall) {
 	}
 
 	if tr.shouldReport(regs) {
-		c.sink.Infof("Unsupported syscall: %s, regs: %+v", c.nameMap.Name(uintptr(sysnr)), regs)
+		name := c.nameMap.Name(uintptr(sysnr))
+		c.sink.Infof("Unsupported syscall %s(%#x,%#x,%#x,%#x,%#x,%#x). It is "+
+			"likely that you can safely ignore this message and that this is not "+
+			"the cause of any error. Please, refer to %s/%s for more information.",
+			name, argVal(0, regs), argVal(1, regs), argVal(2, regs), argVal(3, regs),
+			argVal(4, regs), argVal(5, regs), syscallLink, name)
+
 		tr.onReported(regs)
 	}
 }
diff --git a/runsc/boot/compat_amd64.go b/runsc/boot/compat_amd64.go
index 42b0ca8b0..8eb76b2ba 100644
--- a/runsc/boot/compat_amd64.go
+++ b/runsc/boot/compat_amd64.go
@@ -24,8 +24,12 @@ import (
 	"gvisor.dev/gvisor/pkg/sentry/strace"
 )
 
-// reportLimit is the max number of events that should be reported per tracker.
-const reportLimit = 100
+const (
+	// reportLimit is the max number of events that should be reported per
+	// tracker.
+	reportLimit = 100
+	syscallLink = "https://gvisor.dev/c/linux/amd64"
+)
 
 // newRegs create a empty Registers instance.
 func newRegs() *rpb.Registers {
@@ -36,22 +40,22 @@ func newRegs() *rpb.Registers {
 	}
 }
 
-func argVal(argIdx int, regs *rpb.Registers) uint32 {
+func argVal(argIdx int, regs *rpb.Registers) uint64 {
 	amd64Regs := regs.GetArch().(*rpb.Registers_Amd64).Amd64
 
 	switch argIdx {
 	case 0:
-		return uint32(amd64Regs.Rdi)
+		return amd64Regs.Rdi
 	case 1:
-		return uint32(amd64Regs.Rsi)
+		return amd64Regs.Rsi
 	case 2:
-		return uint32(amd64Regs.Rdx)
+		return amd64Regs.Rdx
 	case 3:
-		return uint32(amd64Regs.R10)
+		return amd64Regs.R10
 	case 4:
-		return uint32(amd64Regs.R8)
+		return amd64Regs.R8
 	case 5:
-		return uint32(amd64Regs.R9)
+		return amd64Regs.R9
 	}
 	panic(fmt.Sprintf("invalid syscall argument index %d", argIdx))
 }
diff --git a/runsc/boot/compat_arm64.go b/runsc/boot/compat_arm64.go
index f784cd237..bce9d95b3 100644
--- a/runsc/boot/compat_arm64.go
+++ b/runsc/boot/compat_arm64.go
@@ -23,8 +23,12 @@ import (
 	"gvisor.dev/gvisor/pkg/sentry/strace"
 )
 
-// reportLimit is the max number of events that should be reported per tracker.
-const reportLimit = 100
+const (
+	// reportLimit is the max number of events that should be reported per
+	// tracker.
+	reportLimit = 100
+	syscallLink = "https://gvisor.dev/c/linux/arm64"
+)
 
 // newRegs create a empty Registers instance.
 func newRegs() *rpb.Registers {
@@ -35,22 +39,22 @@ func newRegs() *rpb.Registers {
 	}
 }
 
-func argVal(argIdx int, regs *rpb.Registers) uint32 {
+func argVal(argIdx int, regs *rpb.Registers) uint64 {
 	arm64Regs := regs.GetArch().(*rpb.Registers_Arm64).Arm64
 
 	switch argIdx {
 	case 0:
-		return uint32(arm64Regs.R0)
+		return arm64Regs.R0
 	case 1:
-		return uint32(arm64Regs.R1)
+		return arm64Regs.R1
 	case 2:
-		return uint32(arm64Regs.R2)
+		return arm64Regs.R2
 	case 3:
-		return uint32(arm64Regs.R3)
+		return arm64Regs.R3
 	case 4:
-		return uint32(arm64Regs.R4)
+		return arm64Regs.R4
 	case 5:
-		return uint32(arm64Regs.R5)
+		return arm64Regs.R5
 	}
 	panic(fmt.Sprintf("invalid syscall argument index %d", argIdx))
 }
diff --git a/runsc/container/container_test.go b/runsc/container/container_test.go
index 7ba301331..1a6d50d0d 100644
--- a/runsc/container/container_test.go
+++ b/runsc/container/container_test.go
@@ -1760,7 +1760,7 @@ func TestUserLog(t *testing.T) {
 	if err != nil {
 		t.Fatalf("error opening user log file %q: %v", userLog, err)
 	}
-	if want := "Unsupported syscall: sched_rr_get_interval"; !strings.Contains(string(out), want) {
+	if want := "Unsupported syscall sched_rr_get_interval("; !strings.Contains(string(out), want) {
 		t.Errorf("user log file doesn't contain %q, out: %s", want, string(out))
 	}
 }