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| author | Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> | 2017-06-29 23:19:16 +0530 |
|---|---|---|
| committer | Michael Ellerman <mpe@ellerman.id.au> | 2017-07-03 23:11:25 +1000 |
| commit | cf7d6fb0672668690ba235280698c9aa6a81010a (patch) | |
| tree | a924fdcc3814d5a6b26c8bad306ef896e990f89d /arch/powerpc/kernel/entry_64.S | |
| parent | 9d6c452352d6535745e734f296335e6695b6df0b (diff) | |
| download | lwn-cf7d6fb0672668690ba235280698c9aa6a81010a.tar.gz lwn-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/kernel/entry_64.S')
| -rw-r--r-- | arch/powerpc/kernel/entry_64.S | 26 |
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) |