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Diffstat (limited to 'arch/s390/kernel/traps.c')
-rw-r--r--arch/s390/kernel/traps.c56
1 files changed, 39 insertions, 17 deletions
diff --git a/arch/s390/kernel/traps.c b/arch/s390/kernel/traps.c
index 52578b5cecbd..24fee11b030d 100644
--- a/arch/s390/kernel/traps.c
+++ b/arch/s390/kernel/traps.c
@@ -27,9 +27,11 @@
#include <linux/uaccess.h>
#include <linux/cpu.h>
#include <linux/entry-common.h>
+#include <linux/kmsan.h>
#include <asm/asm-extable.h>
#include <asm/vtime.h>
#include <asm/fpu.h>
+#include <asm/fault.h>
#include "entry.h"
static inline void __user *get_trap_ip(struct pt_regs *regs)
@@ -262,6 +264,11 @@ static void monitor_event_exception(struct pt_regs *regs)
void kernel_stack_overflow(struct pt_regs *regs)
{
+ /*
+ * Normally regs are unpoisoned by the generic entry code, but
+ * kernel_stack_overflow() is a rare case that is called bypassing it.
+ */
+ kmsan_unpoison_entry_regs(regs);
bust_spinlocks(1);
printk("Kernel stack overflow.\n");
show_regs(regs);
@@ -288,15 +295,16 @@ static void __init test_monitor_call(void)
void __init trap_init(void)
{
+ struct lowcore *lc = get_lowcore();
unsigned long flags;
struct ctlreg cr0;
local_irq_save(flags);
cr0 = local_ctl_clear_bit(0, CR0_LOW_ADDRESS_PROTECTION_BIT);
- psw_bits(S390_lowcore.external_new_psw).mcheck = 1;
- psw_bits(S390_lowcore.program_new_psw).mcheck = 1;
- psw_bits(S390_lowcore.svc_new_psw).mcheck = 1;
- psw_bits(S390_lowcore.io_new_psw).mcheck = 1;
+ psw_bits(lc->external_new_psw).mcheck = 1;
+ psw_bits(lc->program_new_psw).mcheck = 1;
+ psw_bits(lc->svc_new_psw).mcheck = 1;
+ psw_bits(lc->io_new_psw).mcheck = 1;
local_ctl_load(0, &cr0);
local_irq_restore(flags);
local_mcck_enable();
@@ -307,11 +315,27 @@ static void (*pgm_check_table[128])(struct pt_regs *regs);
void noinstr __do_pgm_check(struct pt_regs *regs)
{
- unsigned int trapnr;
+ struct lowcore *lc = get_lowcore();
irqentry_state_t state;
+ unsigned int trapnr;
+ union teid teid;
+
+ teid.val = lc->trans_exc_code;
+ regs->int_code = lc->pgm_int_code;
+ regs->int_parm_long = teid.val;
- regs->int_code = S390_lowcore.pgm_int_code;
- regs->int_parm_long = S390_lowcore.trans_exc_code;
+ /*
+ * In case of a guest fault, short-circuit the fault handler and return.
+ * This way the sie64a() function will return 0; fault address and
+ * other relevant bits are saved in current->thread.gmap_teid, and
+ * the fault number in current->thread.gmap_int_code. KVM will be
+ * able to use this information to handle the fault.
+ */
+ if (test_pt_regs_flag(regs, PIF_GUEST_FAULT)) {
+ current->thread.gmap_teid.val = regs->int_parm_long;
+ current->thread.gmap_int_code = regs->int_code & 0xffff;
+ return;
+ }
state = irqentry_enter(regs);
@@ -324,19 +348,19 @@ void noinstr __do_pgm_check(struct pt_regs *regs)
current->thread.last_break = regs->last_break;
}
- if (S390_lowcore.pgm_code & 0x0200) {
+ if (lc->pgm_code & 0x0200) {
/* transaction abort */
- current->thread.trap_tdb = S390_lowcore.pgm_tdb;
+ current->thread.trap_tdb = lc->pgm_tdb;
}
- if (S390_lowcore.pgm_code & PGM_INT_CODE_PER) {
+ if (lc->pgm_code & PGM_INT_CODE_PER) {
if (user_mode(regs)) {
struct per_event *ev = &current->thread.per_event;
set_thread_flag(TIF_PER_TRAP);
- ev->address = S390_lowcore.per_address;
- ev->cause = S390_lowcore.per_code_combined;
- ev->paid = S390_lowcore.per_access_id;
+ ev->address = lc->per_address;
+ ev->cause = lc->per_code_combined;
+ ev->paid = lc->per_access_id;
} else {
/* PER event in kernel is kprobes */
__arch_local_irq_ssm(regs->psw.mask & ~PSW_MASK_PER);
@@ -400,8 +424,8 @@ static void (*pgm_check_table[128])(struct pt_regs *regs) = {
[0x3b] = do_dat_exception,
[0x3c] = default_trap_handler,
[0x3d] = do_secure_storage_access,
- [0x3e] = do_non_secure_storage_access,
- [0x3f] = do_secure_storage_violation,
+ [0x3e] = default_trap_handler,
+ [0x3f] = default_trap_handler,
[0x40] = monitor_event_exception,
[0x41 ... 0x7f] = default_trap_handler,
};
@@ -412,5 +436,3 @@ static void (*pgm_check_table[128])(struct pt_regs *regs) = {
__stringify(default_trap_handler))
COND_TRAP(do_secure_storage_access);
-COND_TRAP(do_non_secure_storage_access);
-COND_TRAP(do_secure_storage_violation);