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-rw-r--r--arch/powerpc/lib/Makefile1
-rw-r--r--arch/powerpc/lib/feature-fixups.c1
-rw-r--r--arch/powerpc/lib/sstep.c20
-rw-r--r--arch/powerpc/lib/test_emulate_step.c434
4 files changed, 436 insertions, 20 deletions
diff --git a/arch/powerpc/lib/Makefile b/arch/powerpc/lib/Makefile
index 0e649d72fe8d..2b5e09020cfe 100644
--- a/arch/powerpc/lib/Makefile
+++ b/arch/powerpc/lib/Makefile
@@ -20,6 +20,7 @@ obj64-y += copypage_64.o copyuser_64.o usercopy_64.o mem_64.o hweight_64.o \
obj64-$(CONFIG_SMP) += locks.o
obj64-$(CONFIG_ALTIVEC) += vmx-helper.o
+obj64-$(CONFIG_KPROBES_SANITY_TEST) += test_emulate_step.o
obj-y += checksum_$(BITS).o checksum_wrappers.o
diff --git a/arch/powerpc/lib/feature-fixups.c b/arch/powerpc/lib/feature-fixups.c
index 043415f0bdb1..f3917705c686 100644
--- a/arch/powerpc/lib/feature-fixups.c
+++ b/arch/powerpc/lib/feature-fixups.c
@@ -17,6 +17,7 @@
#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/init.h>
+#include <linux/sched/mm.h>
#include <asm/cputable.h>
#include <asm/code-patching.h>
#include <asm/page.h>
diff --git a/arch/powerpc/lib/sstep.c b/arch/powerpc/lib/sstep.c
index 846dba2c6360..9c542ec70c5b 100644
--- a/arch/powerpc/lib/sstep.c
+++ b/arch/powerpc/lib/sstep.c
@@ -1799,8 +1799,6 @@ int __kprobes emulate_step(struct pt_regs *regs, unsigned int instr)
goto instr_done;
case LARX:
- if (regs->msr & MSR_LE)
- return 0;
if (op.ea & (size - 1))
break; /* can't handle misaligned */
if (!address_ok(regs, op.ea, size))
@@ -1823,8 +1821,6 @@ int __kprobes emulate_step(struct pt_regs *regs, unsigned int instr)
goto ldst_done;
case STCX:
- if (regs->msr & MSR_LE)
- return 0;
if (op.ea & (size - 1))
break; /* can't handle misaligned */
if (!address_ok(regs, op.ea, size))
@@ -1849,8 +1845,6 @@ int __kprobes emulate_step(struct pt_regs *regs, unsigned int instr)
goto ldst_done;
case LOAD:
- if (regs->msr & MSR_LE)
- return 0;
err = read_mem(&regs->gpr[op.reg], op.ea, size, regs);
if (!err) {
if (op.type & SIGNEXT)
@@ -1862,8 +1856,6 @@ int __kprobes emulate_step(struct pt_regs *regs, unsigned int instr)
#ifdef CONFIG_PPC_FPU
case LOAD_FP:
- if (regs->msr & MSR_LE)
- return 0;
if (size == 4)
err = do_fp_load(op.reg, do_lfs, op.ea, size, regs);
else
@@ -1872,15 +1864,11 @@ int __kprobes emulate_step(struct pt_regs *regs, unsigned int instr)
#endif
#ifdef CONFIG_ALTIVEC
case LOAD_VMX:
- if (regs->msr & MSR_LE)
- return 0;
err = do_vec_load(op.reg, do_lvx, op.ea & ~0xfUL, regs);
goto ldst_done;
#endif
#ifdef CONFIG_VSX
case LOAD_VSX:
- if (regs->msr & MSR_LE)
- return 0;
err = do_vsx_load(op.reg, do_lxvd2x, op.ea, regs);
goto ldst_done;
#endif
@@ -1903,8 +1891,6 @@ int __kprobes emulate_step(struct pt_regs *regs, unsigned int instr)
goto instr_done;
case STORE:
- if (regs->msr & MSR_LE)
- return 0;
if ((op.type & UPDATE) && size == sizeof(long) &&
op.reg == 1 && op.update_reg == 1 &&
!(regs->msr & MSR_PR) &&
@@ -1917,8 +1903,6 @@ int __kprobes emulate_step(struct pt_regs *regs, unsigned int instr)
#ifdef CONFIG_PPC_FPU
case STORE_FP:
- if (regs->msr & MSR_LE)
- return 0;
if (size == 4)
err = do_fp_store(op.reg, do_stfs, op.ea, size, regs);
else
@@ -1927,15 +1911,11 @@ int __kprobes emulate_step(struct pt_regs *regs, unsigned int instr)
#endif
#ifdef CONFIG_ALTIVEC
case STORE_VMX:
- if (regs->msr & MSR_LE)
- return 0;
err = do_vec_store(op.reg, do_stvx, op.ea & ~0xfUL, regs);
goto ldst_done;
#endif
#ifdef CONFIG_VSX
case STORE_VSX:
- if (regs->msr & MSR_LE)
- return 0;
err = do_vsx_store(op.reg, do_stxvd2x, op.ea, regs);
goto ldst_done;
#endif
diff --git a/arch/powerpc/lib/test_emulate_step.c b/arch/powerpc/lib/test_emulate_step.c
new file mode 100644
index 000000000000..2534c1447554
--- /dev/null
+++ b/arch/powerpc/lib/test_emulate_step.c
@@ -0,0 +1,434 @@
+/*
+ * Simple sanity test for emulate_step load/store instructions.
+ *
+ * Copyright IBM Corp. 2016
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+
+#define pr_fmt(fmt) "emulate_step_test: " fmt
+
+#include <linux/ptrace.h>
+#include <asm/sstep.h>
+#include <asm/ppc-opcode.h>
+
+#define IMM_L(i) ((uintptr_t)(i) & 0xffff)
+
+/*
+ * Defined with TEST_ prefix so it does not conflict with other
+ * definitions.
+ */
+#define TEST_LD(r, base, i) (PPC_INST_LD | ___PPC_RT(r) | \
+ ___PPC_RA(base) | IMM_L(i))
+#define TEST_LWZ(r, base, i) (PPC_INST_LWZ | ___PPC_RT(r) | \
+ ___PPC_RA(base) | IMM_L(i))
+#define TEST_LWZX(t, a, b) (PPC_INST_LWZX | ___PPC_RT(t) | \
+ ___PPC_RA(a) | ___PPC_RB(b))
+#define TEST_STD(r, base, i) (PPC_INST_STD | ___PPC_RS(r) | \
+ ___PPC_RA(base) | ((i) & 0xfffc))
+#define TEST_LDARX(t, a, b, eh) (PPC_INST_LDARX | ___PPC_RT(t) | \
+ ___PPC_RA(a) | ___PPC_RB(b) | \
+ __PPC_EH(eh))
+#define TEST_STDCX(s, a, b) (PPC_INST_STDCX | ___PPC_RS(s) | \
+ ___PPC_RA(a) | ___PPC_RB(b))
+#define TEST_LFSX(t, a, b) (PPC_INST_LFSX | ___PPC_RT(t) | \
+ ___PPC_RA(a) | ___PPC_RB(b))
+#define TEST_STFSX(s, a, b) (PPC_INST_STFSX | ___PPC_RS(s) | \
+ ___PPC_RA(a) | ___PPC_RB(b))
+#define TEST_LFDX(t, a, b) (PPC_INST_LFDX | ___PPC_RT(t) | \
+ ___PPC_RA(a) | ___PPC_RB(b))
+#define TEST_STFDX(s, a, b) (PPC_INST_STFDX | ___PPC_RS(s) | \
+ ___PPC_RA(a) | ___PPC_RB(b))
+#define TEST_LVX(t, a, b) (PPC_INST_LVX | ___PPC_RT(t) | \
+ ___PPC_RA(a) | ___PPC_RB(b))
+#define TEST_STVX(s, a, b) (PPC_INST_STVX | ___PPC_RS(s) | \
+ ___PPC_RA(a) | ___PPC_RB(b))
+#define TEST_LXVD2X(s, a, b) (PPC_INST_LXVD2X | VSX_XX1((s), R##a, R##b))
+#define TEST_STXVD2X(s, a, b) (PPC_INST_STXVD2X | VSX_XX1((s), R##a, R##b))
+
+
+static void __init init_pt_regs(struct pt_regs *regs)
+{
+ static unsigned long msr;
+ static bool msr_cached;
+
+ memset(regs, 0, sizeof(struct pt_regs));
+
+ if (likely(msr_cached)) {
+ regs->msr = msr;
+ return;
+ }
+
+ asm volatile("mfmsr %0" : "=r"(regs->msr));
+
+ regs->msr |= MSR_FP;
+ regs->msr |= MSR_VEC;
+ regs->msr |= MSR_VSX;
+
+ msr = regs->msr;
+ msr_cached = true;
+}
+
+static void __init show_result(char *ins, char *result)
+{
+ pr_info("%-14s : %s\n", ins, result);
+}
+
+static void __init test_ld(void)
+{
+ struct pt_regs regs;
+ unsigned long a = 0x23;
+ int stepped = -1;
+
+ init_pt_regs(&regs);
+ regs.gpr[3] = (unsigned long) &a;
+
+ /* ld r5, 0(r3) */
+ stepped = emulate_step(&regs, TEST_LD(5, 3, 0));
+
+ if (stepped == 1 && regs.gpr[5] == a)
+ show_result("ld", "PASS");
+ else
+ show_result("ld", "FAIL");
+}
+
+static void __init test_lwz(void)
+{
+ struct pt_regs regs;
+ unsigned int a = 0x4545;
+ int stepped = -1;
+
+ init_pt_regs(&regs);
+ regs.gpr[3] = (unsigned long) &a;
+
+ /* lwz r5, 0(r3) */
+ stepped = emulate_step(&regs, TEST_LWZ(5, 3, 0));
+
+ if (stepped == 1 && regs.gpr[5] == a)
+ show_result("lwz", "PASS");
+ else
+ show_result("lwz", "FAIL");
+}
+
+static void __init test_lwzx(void)
+{
+ struct pt_regs regs;
+ unsigned int a[3] = {0x0, 0x0, 0x1234};
+ int stepped = -1;
+
+ init_pt_regs(&regs);
+ regs.gpr[3] = (unsigned long) a;
+ regs.gpr[4] = 8;
+ regs.gpr[5] = 0x8765;
+
+ /* lwzx r5, r3, r4 */
+ stepped = emulate_step(&regs, TEST_LWZX(5, 3, 4));
+ if (stepped == 1 && regs.gpr[5] == a[2])
+ show_result("lwzx", "PASS");
+ else
+ show_result("lwzx", "FAIL");
+}
+
+static void __init test_std(void)
+{
+ struct pt_regs regs;
+ unsigned long a = 0x1234;
+ int stepped = -1;
+
+ init_pt_regs(&regs);
+ regs.gpr[3] = (unsigned long) &a;
+ regs.gpr[5] = 0x5678;
+
+ /* std r5, 0(r3) */
+ stepped = emulate_step(&regs, TEST_STD(5, 3, 0));
+ if (stepped == 1 || regs.gpr[5] == a)
+ show_result("std", "PASS");
+ else
+ show_result("std", "FAIL");
+}
+
+static void __init test_ldarx_stdcx(void)
+{
+ struct pt_regs regs;
+ unsigned long a = 0x1234;
+ int stepped = -1;
+ unsigned long cr0_eq = 0x1 << 29; /* eq bit of CR0 */
+
+ init_pt_regs(&regs);
+ asm volatile("mfcr %0" : "=r"(regs.ccr));
+
+
+ /*** ldarx ***/
+
+ regs.gpr[3] = (unsigned long) &a;
+ regs.gpr[4] = 0;
+ regs.gpr[5] = 0x5678;
+
+ /* ldarx r5, r3, r4, 0 */
+ stepped = emulate_step(&regs, TEST_LDARX(5, 3, 4, 0));
+
+ /*
+ * Don't touch 'a' here. Touching 'a' can do Load/store
+ * of 'a' which result in failure of subsequent stdcx.
+ * Instead, use hardcoded value for comparison.
+ */
+ if (stepped <= 0 || regs.gpr[5] != 0x1234) {
+ show_result("ldarx / stdcx.", "FAIL (ldarx)");
+ return;
+ }
+
+
+ /*** stdcx. ***/
+
+ regs.gpr[5] = 0x9ABC;
+
+ /* stdcx. r5, r3, r4 */
+ stepped = emulate_step(&regs, TEST_STDCX(5, 3, 4));
+
+ /*
+ * Two possible scenarios that indicates successful emulation
+ * of stdcx. :
+ * 1. Reservation is active and store is performed. In this
+ * case cr0.eq bit will be set to 1.
+ * 2. Reservation is not active and store is not performed.
+ * In this case cr0.eq bit will be set to 0.
+ */
+ if (stepped == 1 && ((regs.gpr[5] == a && (regs.ccr & cr0_eq))
+ || (regs.gpr[5] != a && !(regs.ccr & cr0_eq))))
+ show_result("ldarx / stdcx.", "PASS");
+ else
+ show_result("ldarx / stdcx.", "FAIL (stdcx.)");
+}
+
+#ifdef CONFIG_PPC_FPU
+static void __init test_lfsx_stfsx(void)
+{
+ struct pt_regs regs;
+ union {
+ float a;
+ int b;
+ } c;
+ int cached_b;
+ int stepped = -1;
+
+ init_pt_regs(&regs);
+
+
+ /*** lfsx ***/
+
+ c.a = 123.45;
+ cached_b = c.b;
+
+ regs.gpr[3] = (unsigned long) &c.a;
+ regs.gpr[4] = 0;
+
+ /* lfsx frt10, r3, r4 */
+ stepped = emulate_step(&regs, TEST_LFSX(10, 3, 4));
+
+ if (stepped == 1)
+ show_result("lfsx", "PASS");
+ else
+ show_result("lfsx", "FAIL");
+
+
+ /*** stfsx ***/
+
+ c.a = 678.91;
+
+ /* stfsx frs10, r3, r4 */
+ stepped = emulate_step(&regs, TEST_STFSX(10, 3, 4));
+
+ if (stepped == 1 && c.b == cached_b)
+ show_result("stfsx", "PASS");
+ else
+ show_result("stfsx", "FAIL");
+}
+
+static void __init test_lfdx_stfdx(void)
+{
+ struct pt_regs regs;
+ union {
+ double a;
+ long b;
+ } c;
+ long cached_b;
+ int stepped = -1;
+
+ init_pt_regs(&regs);
+
+
+ /*** lfdx ***/
+
+ c.a = 123456.78;
+ cached_b = c.b;
+
+ regs.gpr[3] = (unsigned long) &c.a;
+ regs.gpr[4] = 0;
+
+ /* lfdx frt10, r3, r4 */
+ stepped = emulate_step(&regs, TEST_LFDX(10, 3, 4));
+
+ if (stepped == 1)
+ show_result("lfdx", "PASS");
+ else
+ show_result("lfdx", "FAIL");
+
+
+ /*** stfdx ***/
+
+ c.a = 987654.32;
+
+ /* stfdx frs10, r3, r4 */
+ stepped = emulate_step(&regs, TEST_STFDX(10, 3, 4));
+
+ if (stepped == 1 && c.b == cached_b)
+ show_result("stfdx", "PASS");
+ else
+ show_result("stfdx", "FAIL");
+}
+#else
+static void __init test_lfsx_stfsx(void)
+{
+ show_result("lfsx", "SKIP (CONFIG_PPC_FPU is not set)");
+ show_result("stfsx", "SKIP (CONFIG_PPC_FPU is not set)");
+}
+
+static void __init test_lfdx_stfdx(void)
+{
+ show_result("lfdx", "SKIP (CONFIG_PPC_FPU is not set)");
+ show_result("stfdx", "SKIP (CONFIG_PPC_FPU is not set)");
+}
+#endif /* CONFIG_PPC_FPU */
+
+#ifdef CONFIG_ALTIVEC
+static void __init test_lvx_stvx(void)
+{
+ struct pt_regs regs;
+ union {
+ vector128 a;
+ u32 b[4];
+ } c;
+ u32 cached_b[4];
+ int stepped = -1;
+
+ init_pt_regs(&regs);
+
+
+ /*** lvx ***/
+
+ cached_b[0] = c.b[0] = 923745;
+ cached_b[1] = c.b[1] = 2139478;
+ cached_b[2] = c.b[2] = 9012;
+ cached_b[3] = c.b[3] = 982134;
+
+ regs.gpr[3] = (unsigned long) &c.a;
+ regs.gpr[4] = 0;
+
+ /* lvx vrt10, r3, r4 */
+ stepped = emulate_step(&regs, TEST_LVX(10, 3, 4));
+
+ if (stepped == 1)
+ show_result("lvx", "PASS");
+ else
+ show_result("lvx", "FAIL");
+
+
+ /*** stvx ***/
+
+ c.b[0] = 4987513;
+ c.b[1] = 84313948;
+ c.b[2] = 71;
+ c.b[3] = 498532;
+
+ /* stvx vrs10, r3, r4 */
+ stepped = emulate_step(&regs, TEST_STVX(10, 3, 4));
+
+ if (stepped == 1 && cached_b[0] == c.b[0] && cached_b[1] == c.b[1] &&
+ cached_b[2] == c.b[2] && cached_b[3] == c.b[3])
+ show_result("stvx", "PASS");
+ else
+ show_result("stvx", "FAIL");
+}
+#else
+static void __init test_lvx_stvx(void)
+{
+ show_result("lvx", "SKIP (CONFIG_ALTIVEC is not set)");
+ show_result("stvx", "SKIP (CONFIG_ALTIVEC is not set)");
+}
+#endif /* CONFIG_ALTIVEC */
+
+#ifdef CONFIG_VSX
+static void __init test_lxvd2x_stxvd2x(void)
+{
+ struct pt_regs regs;
+ union {
+ vector128 a;
+ u32 b[4];
+ } c;
+ u32 cached_b[4];
+ int stepped = -1;
+
+ init_pt_regs(&regs);
+
+
+ /*** lxvd2x ***/
+
+ cached_b[0] = c.b[0] = 18233;
+ cached_b[1] = c.b[1] = 34863571;
+ cached_b[2] = c.b[2] = 834;
+ cached_b[3] = c.b[3] = 6138911;
+
+ regs.gpr[3] = (unsigned long) &c.a;
+ regs.gpr[4] = 0;
+
+ /* lxvd2x vsr39, r3, r4 */
+ stepped = emulate_step(&regs, TEST_LXVD2X(39, 3, 4));
+
+ if (stepped == 1)
+ show_result("lxvd2x", "PASS");
+ else
+ show_result("lxvd2x", "FAIL");
+
+
+ /*** stxvd2x ***/
+
+ c.b[0] = 21379463;
+ c.b[1] = 87;
+ c.b[2] = 374234;
+ c.b[3] = 4;
+
+ /* stxvd2x vsr39, r3, r4 */
+ stepped = emulate_step(&regs, TEST_STXVD2X(39, 3, 4));
+
+ if (stepped == 1 && cached_b[0] == c.b[0] && cached_b[1] == c.b[1] &&
+ cached_b[2] == c.b[2] && cached_b[3] == c.b[3])
+ show_result("stxvd2x", "PASS");
+ else
+ show_result("stxvd2x", "FAIL");
+}
+#else
+static void __init test_lxvd2x_stxvd2x(void)
+{
+ show_result("lxvd2x", "SKIP (CONFIG_VSX is not set)");
+ show_result("stxvd2x", "SKIP (CONFIG_VSX is not set)");
+}
+#endif /* CONFIG_VSX */
+
+static int __init test_emulate_step(void)
+{
+ test_ld();
+ test_lwz();
+ test_lwzx();
+ test_std();
+ test_ldarx_stdcx();
+ test_lfsx_stfsx();
+ test_lfdx_stfdx();
+ test_lvx_stvx();
+ test_lxvd2x_stxvd2x();
+
+ return 0;
+}
+late_initcall(test_emulate_step);