Module Name: src
Committed By: rin
Date: Tue Jun 1 00:30:22 UTC 2021
Modified Files:
src/sys/arch/arm/vfp: vfp_init.c
Log Message:
PR port-arm/55790
Fix KASSERT failure with floating-point exception in userland.
Consider the case in which curlwp owns enabled FPU in vfp_handler().
If FPE is raised, we must skip pcu_load(9) rather than just falling
through. Otherwise, KASSERT fires in vfp_state_load(), since curlwp
already owns enabled FPU.
No regression for ATF is introduced.
To generate a diff of this commit:
cvs rdiff -u -r1.73 -r1.74 src/sys/arch/arm/vfp/vfp_init.c
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/sys/arch/arm/vfp/vfp_init.c
diff -u src/sys/arch/arm/vfp/vfp_init.c:1.73 src/sys/arch/arm/vfp/vfp_init.c:1.74
--- src/sys/arch/arm/vfp/vfp_init.c:1.73 Tue Jun 1 00:13:19 2021
+++ src/sys/arch/arm/vfp/vfp_init.c Tue Jun 1 00:30:22 2021
@@ -1,4 +1,4 @@
-/* $NetBSD: vfp_init.c,v 1.73 2021/06/01 00:13:19 rin Exp $ */
+/* $NetBSD: vfp_init.c,v 1.74 2021/06/01 00:30:22 rin Exp $ */
/*
* Copyright (c) 2008 ARM Ltd
@@ -32,7 +32,7 @@
#include "opt_cputypes.h"
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: vfp_init.c,v 1.73 2021/06/01 00:13:19 rin Exp $");
+__KERNEL_RCSID(0, "$NetBSD: vfp_init.c,v 1.74 2021/06/01 00:30:22 rin Exp $");
#include <sys/param.h>
#include <sys/types.h>
@@ -423,6 +423,7 @@ static int
vfp_handler(u_int address, u_int insn, trapframe_t *frame, int fault_code)
{
struct cpu_info * const ci = curcpu();
+ uint32_t fpexc;
/* This shouldn't ever happen. */
if (fault_code != FAULT_USER &&
@@ -436,12 +437,19 @@ vfp_handler(u_int address, u_int insn, t
/*
* If we already own the FPU and it's enabled (and no exception), raise
- * SIGILL. If there is an exception, drop through to raise a SIGFPE.
+ * SIGILL. If there is an exception, raise SIGFPE.
*/
- if (curlwp->l_pcu_cpu[PCU_FPU] == ci
- && (armreg_fpexc_read() & (VFP_FPEXC_EX|VFP_FPEXC_EN)) == VFP_FPEXC_EN) {
+ if (curlwp->l_pcu_cpu[PCU_FPU] == ci) {
KASSERT(ci->ci_pcu_curlwp[PCU_FPU] == curlwp);
- return 1;
+
+ fpexc = armreg_fpexc_read();
+ if (fpexc & VFP_FPEXC_EN) {
+ if ((fpexc & VFP_FPEXC_EX) == 0) {
+ return 1; /* SIGILL */
+ } else {
+ goto fpe; /* SIGFPE; skip pcu_load(9) */
+ }
+ }
}
/*
@@ -449,11 +457,12 @@ vfp_handler(u_int address, u_int insn, t
*/
pcu_load(&arm_vfp_ops);
- uint32_t fpexc = armreg_fpexc_read();
+ fpexc = armreg_fpexc_read();
if (fpexc & VFP_FPEXC_EX) {
ksiginfo_t ksi;
KASSERT(fpexc & VFP_FPEXC_EN);
+fpe:
curcpu()->ci_vfp_evs[2].ev_count++;
/*
