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Diffstat (limited to 'arch/s390/kernel/nmi.c')
-rw-r--r--arch/s390/kernel/nmi.c129
1 files changed, 77 insertions, 52 deletions
diff --git a/arch/s390/kernel/nmi.c b/arch/s390/kernel/nmi.c
index 11f8c296f60d..20f8e1868853 100644
--- a/arch/s390/kernel/nmi.c
+++ b/arch/s390/kernel/nmi.c
@@ -189,12 +189,16 @@ void noinstr s390_handle_mcck(void)
* returns 0 if all required registers are available
* returns 1 otherwise
*/
-static int notrace s390_check_registers(union mci mci, int umode)
+static int notrace s390_validate_registers(union mci mci, int umode)
{
+ struct mcesa *mcesa;
+ void *fpt_save_area;
union ctlreg2 cr2;
int kill_task;
+ u64 zero;
kill_task = 0;
+ zero = 0;
if (!mci.gr) {
/*
@@ -205,14 +209,6 @@ static int notrace s390_check_registers(union mci mci, int umode)
s390_handle_damage();
kill_task = 1;
}
- /* Check control registers */
- if (!mci.cr) {
- /*
- * Control registers have unknown contents.
- * Can't recover and therefore stopping machine.
- */
- s390_handle_damage();
- }
if (!mci.fp) {
/*
* Floating point registers can't be restored. If the
@@ -225,35 +221,89 @@ static int notrace s390_check_registers(union mci mci, int umode)
if (!test_cpu_flag(CIF_FPU))
kill_task = 1;
}
+ fpt_save_area = &S390_lowcore.floating_pt_save_area;
if (!mci.fc) {
/*
* Floating point control register can't be restored.
* If the kernel currently uses the floating pointer
* registers and needs the FPC register the system is
* stopped. If the process has its floating pointer
- * registers loaded it is terminated.
+ * registers loaded it is terminated. Otherwise the
+ * FPC is just validated.
*/
if (S390_lowcore.fpu_flags & KERNEL_FPC)
s390_handle_damage();
+ asm volatile(
+ " lfpc %0\n"
+ :
+ : "Q" (zero));
if (!test_cpu_flag(CIF_FPU))
kill_task = 1;
+ } else {
+ asm volatile(
+ " lfpc %0\n"
+ :
+ : "Q" (S390_lowcore.fpt_creg_save_area));
}
- if (MACHINE_HAS_VX) {
+ mcesa = (struct mcesa *)(S390_lowcore.mcesad & MCESA_ORIGIN_MASK);
+ if (!MACHINE_HAS_VX) {
+ /* Validate floating point registers */
+ asm volatile(
+ " ld 0,0(%0)\n"
+ " ld 1,8(%0)\n"
+ " ld 2,16(%0)\n"
+ " ld 3,24(%0)\n"
+ " ld 4,32(%0)\n"
+ " ld 5,40(%0)\n"
+ " ld 6,48(%0)\n"
+ " ld 7,56(%0)\n"
+ " ld 8,64(%0)\n"
+ " ld 9,72(%0)\n"
+ " ld 10,80(%0)\n"
+ " ld 11,88(%0)\n"
+ " ld 12,96(%0)\n"
+ " ld 13,104(%0)\n"
+ " ld 14,112(%0)\n"
+ " ld 15,120(%0)\n"
+ :
+ : "a" (fpt_save_area)
+ : "memory");
+ } else {
+ /* Validate vector registers */
+ union ctlreg0 cr0;
+
if (!mci.vr) {
/*
* Vector registers can't be restored. If the kernel
* currently uses vector registers the system is
* stopped. If the process has its vector registers
- * loaded it is terminated.
+ * loaded it is terminated. Otherwise just validate
+ * the registers.
*/
if (S390_lowcore.fpu_flags & KERNEL_VXR)
s390_handle_damage();
if (!test_cpu_flag(CIF_FPU))
kill_task = 1;
}
+ cr0.val = S390_lowcore.cregs_save_area[0];
+ cr0.afp = cr0.vx = 1;
+ __ctl_load(cr0.val, 0, 0);
+ asm volatile(
+ " la 1,%0\n"
+ " .word 0xe70f,0x1000,0x0036\n" /* vlm 0,15,0(1) */
+ " .word 0xe70f,0x1100,0x0c36\n" /* vlm 16,31,256(1) */
+ :
+ : "Q" (*(struct vx_array *)mcesa->vector_save_area)
+ : "1");
+ __ctl_load(S390_lowcore.cregs_save_area[0], 0, 0);
}
- /* Check if access registers are valid */
+ /* Validate access registers */
+ asm volatile(
+ " lam 0,15,0(%0)\n"
+ :
+ : "a" (&S390_lowcore.access_regs_save_area)
+ : "memory");
if (!mci.ar) {
/*
* Access registers have unknown contents.
@@ -261,7 +311,7 @@ static int notrace s390_check_registers(union mci mci, int umode)
*/
kill_task = 1;
}
- /* Check guarded storage registers */
+ /* Validate guarded storage registers */
cr2.val = S390_lowcore.cregs_save_area[2];
if (cr2.gse) {
if (!mci.gs) {
@@ -271,31 +321,26 @@ static int notrace s390_check_registers(union mci mci, int umode)
* It has to be terminated.
*/
kill_task = 1;
+ } else {
+ load_gs_cb((struct gs_cb *)mcesa->guarded_storage_save_area);
}
}
- /* Check if old PSW is valid */
- if (!mci.wp) {
- /*
- * Can't tell if we come from user or kernel mode
- * -> stopping machine.
- */
- s390_handle_damage();
- }
- /* Check for invalid kernel instruction address */
- if (!mci.ia && !umode) {
- /*
- * The instruction address got lost while running
- * in the kernel -> stopping machine.
- */
- s390_handle_damage();
- }
+ /*
+ * The getcpu vdso syscall reads CPU number from the programmable
+ * field of the TOD clock. Disregard the TOD programmable register
+ * validity bit and load the CPU number into the TOD programmable
+ * field unconditionally.
+ */
+ set_tod_programmable_field(raw_smp_processor_id());
+ /* Validate clock comparator register */
+ set_clock_comparator(S390_lowcore.clock_comparator);
if (!mci.ms || !mci.pm || !mci.ia)
kill_task = 1;
return kill_task;
}
-NOKPROBE_SYMBOL(s390_check_registers);
+NOKPROBE_SYMBOL(s390_validate_registers);
/*
* Backup the guest's machine check info to its description block
@@ -353,11 +398,6 @@ int notrace s390_do_machine_check(struct pt_regs *regs)
mci.val = S390_lowcore.mcck_interruption_code;
mcck = this_cpu_ptr(&cpu_mcck);
- if (mci.sd) {
- /* System damage -> stopping machine */
- s390_handle_damage();
- }
-
/*
* Reinject the instruction processing damages' machine checks
* including Delayed Access Exception into the guest
@@ -398,7 +438,7 @@ int notrace s390_do_machine_check(struct pt_regs *regs)
s390_handle_damage();
}
}
- if (s390_check_registers(mci, user_mode(regs))) {
+ if (s390_validate_registers(mci, user_mode(regs))) {
/*
* Couldn't restore all register contents for the
* user space process -> mark task for termination.
@@ -428,21 +468,6 @@ int notrace s390_do_machine_check(struct pt_regs *regs)
mcck_pending = 1;
}
- /*
- * Reinject storage related machine checks into the guest if they
- * happen when the guest is running.
- */
- if (!test_cpu_flag(CIF_MCCK_GUEST)) {
- if (mci.se)
- /* Storage error uncorrected */
- s390_handle_damage();
- if (mci.ke)
- /* Storage key-error uncorrected */
- s390_handle_damage();
- if (mci.ds && mci.fa)
- /* Storage degradation */
- s390_handle_damage();
- }
if (mci.cp) {
/* Channel report word pending */
mcck->channel_report = 1;
generated by cgit v1.2.3 (git 2.25.1) at 2024-09-21 06:48:17 +0000