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authorLinus Torvalds <torvalds@linux-foundation.org>2022-03-05 11:25:26 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2022-03-05 11:25:26 -0800
commitf9026e19a44d965793d25e7a02b0d6c1bcafd8f5 (patch)
treebb0e70b968b7c2518682c7fd5082421a3308ac5e /arch/s390
parentac84e82f78cb55ce8e760e0b5887d56efd78d6bc (diff)
parentc194dad21025dfd043210912653baab823bdff67 (diff)
Merge tag 's390-5.17-5' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux
Pull s390 fixes from Vasily Gorbik: - Fix HAVE_DYNAMIC_FTRACE_WITH_ARGS implementation by providing correct switching between ftrace_caller/ftrace_regs_caller and supplying pt_regs only when ftrace_regs_caller is activated. - Fix exception table sorting. - Fix breakage of kdump tooling by preserving metadata it cannot function without. * tag 's390-5.17-5' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: s390/extable: fix exception table sorting s390/ftrace: fix arch_ftrace_get_regs implementation s390/ftrace: fix ftrace_caller/ftrace_regs_caller generation s390/setup: preserve memory at OLDMEM_BASE and OLDMEM_SIZE
Diffstat (limited to 'arch/s390')
-rw-r--r--arch/s390/include/asm/extable.h9
-rw-r--r--arch/s390/include/asm/ftrace.h10
-rw-r--r--arch/s390/include/asm/ptrace.h2
-rw-r--r--arch/s390/kernel/ftrace.c37
-rw-r--r--arch/s390/kernel/mcount.S9
-rw-r--r--arch/s390/kernel/setup.c2
6 files changed, 62 insertions, 7 deletions
diff --git a/arch/s390/include/asm/extable.h b/arch/s390/include/asm/extable.h
index 16dc57dd90b3..8511f0e59290 100644
--- a/arch/s390/include/asm/extable.h
+++ b/arch/s390/include/asm/extable.h
@@ -69,8 +69,13 @@ static inline void swap_ex_entry_fixup(struct exception_table_entry *a,
{
a->fixup = b->fixup + delta;
b->fixup = tmp.fixup - delta;
- a->handler = b->handler + delta;
- b->handler = tmp.handler - delta;
+ a->handler = b->handler;
+ if (a->handler)
+ a->handler += delta;
+ b->handler = tmp.handler;
+ if (b->handler)
+ b->handler -= delta;
}
+#define swap_ex_entry_fixup swap_ex_entry_fixup
#endif
diff --git a/arch/s390/include/asm/ftrace.h b/arch/s390/include/asm/ftrace.h
index 267f70f4393f..6f80ec9c04be 100644
--- a/arch/s390/include/asm/ftrace.h
+++ b/arch/s390/include/asm/ftrace.h
@@ -47,15 +47,17 @@ struct ftrace_regs {
static __always_inline struct pt_regs *arch_ftrace_get_regs(struct ftrace_regs *fregs)
{
- return &fregs->regs;
+ struct pt_regs *regs = &fregs->regs;
+
+ if (test_pt_regs_flag(regs, PIF_FTRACE_FULL_REGS))
+ return regs;
+ return NULL;
}
static __always_inline void ftrace_instruction_pointer_set(struct ftrace_regs *fregs,
unsigned long ip)
{
- struct pt_regs *regs = arch_ftrace_get_regs(fregs);
-
- regs->psw.addr = ip;
+ fregs->regs.psw.addr = ip;
}
/*
diff --git a/arch/s390/include/asm/ptrace.h b/arch/s390/include/asm/ptrace.h
index 4ffa8e7f0ed3..ddb70fb13fbc 100644
--- a/arch/s390/include/asm/ptrace.h
+++ b/arch/s390/include/asm/ptrace.h
@@ -15,11 +15,13 @@
#define PIF_EXECVE_PGSTE_RESTART 1 /* restart execve for PGSTE binaries */
#define PIF_SYSCALL_RET_SET 2 /* return value was set via ptrace */
#define PIF_GUEST_FAULT 3 /* indicates program check in sie64a */
+#define PIF_FTRACE_FULL_REGS 4 /* all register contents valid (ftrace) */
#define _PIF_SYSCALL BIT(PIF_SYSCALL)
#define _PIF_EXECVE_PGSTE_RESTART BIT(PIF_EXECVE_PGSTE_RESTART)
#define _PIF_SYSCALL_RET_SET BIT(PIF_SYSCALL_RET_SET)
#define _PIF_GUEST_FAULT BIT(PIF_GUEST_FAULT)
+#define _PIF_FTRACE_FULL_REGS BIT(PIF_FTRACE_FULL_REGS)
#ifndef __ASSEMBLY__
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/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);