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authorNaveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>2017-06-29 23:19:16 +0530
committerMichael Ellerman <mpe@ellerman.id.au>2017-07-03 23:11:25 +1000
commitcf7d6fb0672668690ba235280698c9aa6a81010a (patch)
treea924fdcc3814d5a6b26c8bad306ef896e990f89d /arch/powerpc
parentpowerpc/64s: Convert .L__replay_interrupt_return to a local label (diff)
downloadlinux-dev-cf7d6fb0672668690ba235280698c9aa6a81010a.tar.xz
linux-dev-cf7d6fb0672668690ba235280698c9aa6a81010a.zip
powerpc/64s: Blacklist system_call() and system_call_common() from kprobes
Convert some of the symbols into private symbols and blacklist system_call_common() and system_call() from kprobes. We can't take a trap at parts of these functions as either MSR_RI is unset or the kernel stack pointer is not yet setup. Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org> Reviewed-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> [mpe: Don't convert system_call_common to _GLOBAL()] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Diffstat (limited to 'arch/powerpc')
-rw-r--r--arch/powerpc/kernel/entry_64.S26
1 files changed, 14 insertions, 12 deletions
diff --git a/arch/powerpc/kernel/entry_64.S b/arch/powerpc/kernel/entry_64.S
index da9486e2fd89..410e19295259 100644
--- a/arch/powerpc/kernel/entry_64.S
+++ b/arch/powerpc/kernel/entry_64.S
@@ -57,7 +57,7 @@ system_call_common:
#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
BEGIN_FTR_SECTION
extrdi. r10, r12, 1, (63-MSR_TS_T_LG) /* transaction active? */
- bne tabort_syscall
+ bne .Ltabort_syscall
END_FTR_SECTION_IFSET(CPU_FTR_TM)
#endif
andi. r10,r12,MSR_PR
@@ -152,9 +152,9 @@ END_FW_FTR_SECTION_IFSET(FW_FEATURE_SPLPAR)
CURRENT_THREAD_INFO(r11, r1)
ld r10,TI_FLAGS(r11)
andi. r11,r10,_TIF_SYSCALL_DOTRACE
- bne syscall_dotrace /* does not return */
+ bne .Lsyscall_dotrace /* does not return */
cmpldi 0,r0,NR_syscalls
- bge- syscall_enosys
+ bge- .Lsyscall_enosys
system_call: /* label this so stack traces look sane */
/*
@@ -208,7 +208,7 @@ system_call: /* label this so stack traces look sane */
ld r9,TI_FLAGS(r12)
li r11,-MAX_ERRNO
andi. r0,r9,(_TIF_SYSCALL_DOTRACE|_TIF_SINGLESTEP|_TIF_USER_WORK_MASK|_TIF_PERSYSCALL_MASK)
- bne- syscall_exit_work
+ bne- .Lsyscall_exit_work
/* If MSR_FP and MSR_VEC are set in user msr, then no need to restore */
li r7,MSR_FP
@@ -217,12 +217,12 @@ system_call: /* label this so stack traces look sane */
#endif
and r0,r8,r7
cmpd r0,r7
- bne syscall_restore_math
+ bne .Lsyscall_restore_math
.Lsyscall_restore_math_cont:
cmpld r3,r11
ld r5,_CCR(r1)
- bge- syscall_error
+ bge- .Lsyscall_error
.Lsyscall_error_cont:
ld r7,_NIP(r1)
BEGIN_FTR_SECTION
@@ -248,13 +248,13 @@ END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR)
RFI
b . /* prevent speculative execution */
-syscall_error:
+.Lsyscall_error:
oris r5,r5,0x1000 /* Set SO bit in CR */
neg r3,r3
std r5,_CCR(r1)
b .Lsyscall_error_cont
-syscall_restore_math:
+.Lsyscall_restore_math:
/*
* Some initial tests from restore_math to avoid the heavyweight
* C code entry and MSR manipulations.
@@ -289,7 +289,7 @@ syscall_restore_math:
b .Lsyscall_restore_math_cont
/* Traced system call support */
-syscall_dotrace:
+.Lsyscall_dotrace:
bl save_nvgprs
addi r3,r1,STACK_FRAME_OVERHEAD
bl do_syscall_trace_enter
@@ -322,11 +322,11 @@ syscall_dotrace:
b .Lsyscall_exit
-syscall_enosys:
+.Lsyscall_enosys:
li r3,-ENOSYS
b .Lsyscall_exit
-syscall_exit_work:
+.Lsyscall_exit_work:
#ifdef CONFIG_PPC_BOOK3S
li r10,MSR_RI
mtmsrd r10,1 /* Restore RI */
@@ -386,7 +386,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR)
b ret_from_except
#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
-tabort_syscall:
+.Ltabort_syscall:
/* Firstly we need to enable TM in the kernel */
mfmsr r10
li r9, 1
@@ -412,6 +412,8 @@ tabort_syscall:
rfid
b . /* prevent speculative execution */
#endif
+_ASM_NOKPROBE_SYMBOL(system_call_common);
+_ASM_NOKPROBE_SYMBOL(system_call);
/* Save non-volatile GPRs, if not already saved. */
_GLOBAL(save_nvgprs)