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-rw-r--r--arch/s390/kernel/ftrace.c37
-rw-r--r--arch/s390/kernel/mcount.S9
-rw-r--r--arch/s390/kernel/module.c37
-rw-r--r--arch/s390/kernel/nmi.c27
-rw-r--r--arch/s390/kernel/setup.c2
5 files changed, 87 insertions, 25 deletions
diff --git a/arch/s390/kernel/ftrace.c b/arch/s390/kernel/ftrace.c
index 21d62d8b6b9a..89c0870d5679 100644
--- a/arch/s390/kernel/ftrace.c
+++ b/arch/s390/kernel/ftrace.c
@@ -159,9 +159,38 @@ int ftrace_init_nop(struct module *mod, struct dyn_ftrace *rec)
return 0;
}
+static struct ftrace_hotpatch_trampoline *ftrace_get_trampoline(struct dyn_ftrace *rec)
+{
+ struct ftrace_hotpatch_trampoline *trampoline;
+ struct ftrace_insn insn;
+ s64 disp;
+ u16 opc;
+
+ if (copy_from_kernel_nofault(&insn, (void *)rec->ip, sizeof(insn)))
+ return ERR_PTR(-EFAULT);
+ disp = (s64)insn.disp * 2;
+ trampoline = (void *)(rec->ip + disp);
+ if (get_kernel_nofault(opc, &trampoline->brasl_opc))
+ return ERR_PTR(-EFAULT);
+ if (opc != 0xc015)
+ return ERR_PTR(-EINVAL);
+ return trampoline;
+}
+
int ftrace_modify_call(struct dyn_ftrace *rec, unsigned long old_addr,
unsigned long addr)
{
+ struct ftrace_hotpatch_trampoline *trampoline;
+ u64 old;
+
+ trampoline = ftrace_get_trampoline(rec);
+ if (IS_ERR(trampoline))
+ return PTR_ERR(trampoline);
+ if (get_kernel_nofault(old, &trampoline->interceptor))
+ return -EFAULT;
+ if (old != old_addr)
+ return -EINVAL;
+ s390_kernel_write(&trampoline->interceptor, &addr, sizeof(addr));
return 0;
}
@@ -188,6 +217,12 @@ static void brcl_enable(void *brcl)
int ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr)
{
+ struct ftrace_hotpatch_trampoline *trampoline;
+
+ trampoline = ftrace_get_trampoline(rec);
+ if (IS_ERR(trampoline))
+ return PTR_ERR(trampoline);
+ s390_kernel_write(&trampoline->interceptor, &addr, sizeof(addr));
brcl_enable((void *)rec->ip);
return 0;
}
@@ -291,7 +326,7 @@ void kprobe_ftrace_handler(unsigned long ip, unsigned long parent_ip,
regs = ftrace_get_regs(fregs);
p = get_kprobe((kprobe_opcode_t *)ip);
- if (unlikely(!p) || kprobe_disabled(p))
+ if (!regs || unlikely(!p) || kprobe_disabled(p))
goto out;
if (kprobe_running()) {
diff --git a/arch/s390/kernel/mcount.S b/arch/s390/kernel/mcount.S
index 39bcc0e39a10..a24177dcd12a 100644
--- a/arch/s390/kernel/mcount.S
+++ b/arch/s390/kernel/mcount.S
@@ -27,6 +27,7 @@ ENDPROC(ftrace_stub)
#define STACK_PTREGS_GPRS (STACK_PTREGS + __PT_GPRS)
#define STACK_PTREGS_PSW (STACK_PTREGS + __PT_PSW)
#define STACK_PTREGS_ORIG_GPR2 (STACK_PTREGS + __PT_ORIG_GPR2)
+#define STACK_PTREGS_FLAGS (STACK_PTREGS + __PT_FLAGS)
#ifdef __PACK_STACK
/* allocate just enough for r14, r15 and backchain */
#define TRACED_FUNC_FRAME_SIZE 24
@@ -57,6 +58,14 @@ ENDPROC(ftrace_stub)
.if \allregs == 1
stg %r14,(STACK_PTREGS_PSW)(%r15)
stosm (STACK_PTREGS_PSW)(%r15),0
+#ifdef CONFIG_HAVE_MARCH_Z10_FEATURES
+ mvghi STACK_PTREGS_FLAGS(%r15),_PIF_FTRACE_FULL_REGS
+#else
+ lghi %r14,_PIF_FTRACE_FULL_REGS
+ stg %r14,STACK_PTREGS_FLAGS(%r15)
+#endif
+ .else
+ xc STACK_PTREGS_FLAGS(8,%r15),STACK_PTREGS_FLAGS(%r15)
.endif
lg %r14,(__SF_GPRS+8*8)(%r1) # restore original return address
diff --git a/arch/s390/kernel/module.c b/arch/s390/kernel/module.c
index d52d85367bf7..b032e556eeb7 100644
--- a/arch/s390/kernel/module.c
+++ b/arch/s390/kernel/module.c
@@ -33,7 +33,7 @@
#define DEBUGP(fmt , ...)
#endif
-#define PLT_ENTRY_SIZE 20
+#define PLT_ENTRY_SIZE 22
void *module_alloc(unsigned long size)
{
@@ -341,27 +341,26 @@ static int apply_rela(Elf_Rela *rela, Elf_Addr base, Elf_Sym *symtab,
case R_390_PLTOFF32: /* 32 bit offset from GOT to PLT. */
case R_390_PLTOFF64: /* 16 bit offset from GOT to PLT. */
if (info->plt_initialized == 0) {
- unsigned int insn[5];
- unsigned int *ip = me->core_layout.base +
- me->arch.plt_offset +
- info->plt_offset;
-
- insn[0] = 0x0d10e310; /* basr 1,0 */
- insn[1] = 0x100a0004; /* lg 1,10(1) */
+ unsigned char insn[PLT_ENTRY_SIZE];
+ char *plt_base;
+ char *ip;
+
+ plt_base = me->core_layout.base + me->arch.plt_offset;
+ ip = plt_base + info->plt_offset;
+ *(int *)insn = 0x0d10e310; /* basr 1,0 */
+ *(int *)&insn[4] = 0x100c0004; /* lg 1,12(1) */
if (IS_ENABLED(CONFIG_EXPOLINE) && !nospec_disable) {
- unsigned int *ij;
- ij = me->core_layout.base +
- me->arch.plt_offset +
- me->arch.plt_size - PLT_ENTRY_SIZE;
- insn[2] = 0xa7f40000 + /* j __jump_r1 */
- (unsigned int)(u16)
- (((unsigned long) ij - 8 -
- (unsigned long) ip) / 2);
+ char *jump_r1;
+
+ jump_r1 = plt_base + me->arch.plt_size -
+ PLT_ENTRY_SIZE;
+ /* brcl 0xf,__jump_r1 */
+ *(short *)&insn[8] = 0xc0f4;
+ *(int *)&insn[10] = (jump_r1 - (ip + 8)) / 2;
} else {
- insn[2] = 0x07f10000; /* br %r1 */
+ *(int *)&insn[8] = 0x07f10000; /* br %r1 */
}
- insn[3] = (unsigned int) (val >> 32);
- insn[4] = (unsigned int) val;
+ *(long *)&insn[14] = val;
write(ip, insn, sizeof(insn));
info->plt_initialized = 1;
diff --git a/arch/s390/kernel/nmi.c b/arch/s390/kernel/nmi.c
index 0c9e894913dc..651a51914e34 100644
--- a/arch/s390/kernel/nmi.c
+++ b/arch/s390/kernel/nmi.c
@@ -264,7 +264,14 @@ static int notrace s390_validate_registers(union mci mci, int umode)
/* Validate vector registers */
union ctlreg0 cr0;
- if (!mci.vr) {
+ /*
+ * The vector validity must only be checked if not running a
+ * KVM guest. For KVM guests the machine check is forwarded by
+ * KVM and it is the responsibility of the guest to take
+ * appropriate actions. The host vector or FPU values have been
+ * saved by KVM and will be restored by KVM.
+ */
+ if (!mci.vr && !test_cpu_flag(CIF_MCCK_GUEST)) {
/*
* Vector registers can't be restored. If the kernel
* currently uses vector registers the system is
@@ -307,11 +314,21 @@ static int notrace s390_validate_registers(union mci mci, int umode)
if (cr2.gse) {
if (!mci.gs) {
/*
- * Guarded storage register can't be restored and
- * the current processes uses guarded storage.
- * It has to be terminated.
+ * 2 cases:
+ * - machine check in kernel or userspace
+ * - machine check while running SIE (KVM guest)
+ * For kernel or userspace the userspace values of
+ * guarded storage control can not be recreated, the
+ * process must be terminated.
+ * For SIE the guest values of guarded storage can not
+ * be recreated. This is either due to a bug or due to
+ * GS being disabled in the guest. The guest will be
+ * notified by KVM code and the guests machine check
+ * handling must take care of this. The host values
+ * are saved by KVM and are not affected.
*/
- kill_task = 1;
+ if (!test_cpu_flag(CIF_MCCK_GUEST))
+ kill_task = 1;
} else {
load_gs_cb((struct gs_cb *)mcesa->guarded_storage_save_area);
}
diff --git a/arch/s390/kernel/setup.c b/arch/s390/kernel/setup.c
index f2c25d113e7b..05327be3a982 100644
--- a/arch/s390/kernel/setup.c
+++ b/arch/s390/kernel/setup.c
@@ -800,6 +800,8 @@ static void __init check_initrd(void)
static void __init reserve_kernel(void)
{
memblock_reserve(0, STARTUP_NORMAL_OFFSET);
+ memblock_reserve(OLDMEM_BASE, sizeof(unsigned long));
+ memblock_reserve(OLDMEM_SIZE, sizeof(unsigned long));
memblock_reserve(__amode31_base, __eamode31 - __samode31);
memblock_reserve(__pa(sclp_early_sccb), EXT_SCCB_READ_SCP);
memblock_reserve(__pa(_stext), _end - _stext);
generated by cgit (git 2.34.1) at 2024-05-28 14:01:33 +0000