Per the ISA, a Trace interrupt is not generated for a system call
[vectored] instruction. Reject uprobes on such instructions as we are
not emulating a system call [vectored] instruction anymore.
Signed-off-by: Naveen N. Rao <naveen.n....@linux.vnet.ibm.com>
[np: Switch to pr_info_ratelimited]
Signed-off-by: Nicholas Piggin <npig...@gmail.com>
---
arch/powerpc/include/asm/ppc-opcode.h | 1 +
arch/powerpc/kernel/uprobes.c | 6 ++++++
2 files changed, 7 insertions(+)
diff --git a/arch/powerpc/include/asm/ppc-opcode.h
b/arch/powerpc/include/asm/ppc-opcode.h
index 9675303b724e..8bbe16ce5173 100644
--- a/arch/powerpc/include/asm/ppc-opcode.h
+++ b/arch/powerpc/include/asm/ppc-opcode.h
@@ -411,6 +411,7 @@
#define PPC_RAW_DCBFPS(a, b) (0x7c0000ac | ___PPC_RA(a) |
___PPC_RB(b) | (4 << 21))
#define PPC_RAW_DCBSTPS(a, b) (0x7c0000ac | ___PPC_RA(a) |
___PPC_RB(b) | (6 << 21))
#define PPC_RAW_SC() (0x44000002)
+#define PPC_RAW_SCV() (0x44000001)
#define PPC_RAW_SYNC() (0x7c0004ac)
#define PPC_RAW_ISYNC() (0x4c00012c)
diff --git a/arch/powerpc/kernel/uprobes.c b/arch/powerpc/kernel/uprobes.c
index c6975467d9ff..3779fde804bd 100644
--- a/arch/powerpc/kernel/uprobes.c
+++ b/arch/powerpc/kernel/uprobes.c
@@ -41,6 +41,12 @@ int arch_uprobe_analyze_insn(struct arch_uprobe *auprobe,
if (addr & 0x03)
return -EINVAL;
+ if (ppc_inst_val(ppc_inst_read(auprobe->insn)) == PPC_RAW_SC() ||
+ ppc_inst_val(ppc_inst_read(auprobe->insn)) == PPC_RAW_SCV()) {
+ pr_info_ratelimited("Rejecting uprobe on system call
instruction\n");
+ return -EINVAL;
+ }
+
if (cpu_has_feature(CPU_FTR_ARCH_31) &&
ppc_inst_prefixed(ppc_inst_read(auprobe->insn)) &&
(addr & 0x3f) == 60) {
--
2.23.0
