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-rw-r--r--arch/arm/Kconfig3
-rw-r--r--arch/arm/include/asm/module.h7
-rw-r--r--arch/arm/include/asm/runtime-patch.h208
-rw-r--r--arch/arm/kernel/Makefile1
-rw-r--r--arch/arm/kernel/module.c9
-rw-r--r--arch/arm/kernel/runtime-patch.c193
-rw-r--r--arch/arm/kernel/setup.c3
-rw-r--r--arch/arm/kernel/vmlinux.lds.S10
8 files changed, 433 insertions, 1 deletions
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index f0bf7e9d7c5..4e4abbfd929 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -67,6 +67,9 @@ config ARM
config ARM_HAS_SG_CHAIN
bool
+config ARM_RUNTIME_PATCH
+ bool
+
config NEED_SG_DMA_LENGTH
bool
diff --git a/arch/arm/include/asm/module.h b/arch/arm/include/asm/module.h
index 0d3a28dbc8e..c4ebe522ca4 100644
--- a/arch/arm/include/asm/module.h
+++ b/arch/arm/include/asm/module.h
@@ -39,9 +39,16 @@ struct mod_arch_specific {
#define MODULE_ARCH_VERMAGIC_ARMTHUMB ""
#endif
+#ifdef CONFIG_ARM_RUNTIME_PATCH
+#define MODULE_ARCH_VERMAGIC_RT_PATCH "rt-patch "
+#else
+#define MODULE_ARCH_VERMAGIC_RT_PATCH ""
+#endif
+
#define MODULE_ARCH_VERMAGIC \
MODULE_ARCH_VERMAGIC_ARMVSN \
MODULE_ARCH_VERMAGIC_ARMTHUMB \
+ MODULE_ARCH_VERMAGIC_RT_PATCH \
MODULE_ARCH_VERMAGIC_P2V
#endif /* _ASM_ARM_MODULE_H */
diff --git a/arch/arm/include/asm/runtime-patch.h b/arch/arm/include/asm/runtime-patch.h
new file mode 100644
index 00000000000..366444d7eef
--- /dev/null
+++ b/arch/arm/include/asm/runtime-patch.h
@@ -0,0 +1,208 @@
+/*
+ * arch/arm/include/asm/runtime-patch.h
+ * Note: this file should not be included by non-asm/.h files
+ *
+ * Copyright 2012 Texas Instruments, Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+#ifndef __ASM_ARM_RUNTIME_PATCH_H
+#define __ASM_ARM_RUNTIME_PATCH_H
+
+#include <linux/stringify.h>
+
+#ifndef __ASSEMBLY__
+
+#ifdef CONFIG_ARM_RUNTIME_PATCH
+
+struct patch_info {
+ void *insn;
+ u16 type;
+ u8 insn_size;
+ u8 data_size;
+ u32 data[0];
+};
+
+#define PATCH_IMM8 0x0001
+struct patch_info_imm8 {
+ u32 *imm;
+ u32 insn;
+};
+
+#define patch_next(p) ((void *)(p) + sizeof(*(p)) + (p)->data_size)
+#define patch_data(p) ((void *)&(p)->data[0])
+
+#define patch_stub(type, code, patch_data, ...) \
+ __asm__("@ patch stub\n" \
+ "1:\n" \
+ code \
+ "2:\n" \
+ " .pushsection .runtime.patch.table, \"a\"\n" \
+ "3:\n" \
+ " .word 1b\n" \
+ " .hword (" __stringify(type) ")\n" \
+ " .byte (2b-1b)\n" \
+ " .byte (5f-4f)\n" \
+ "4:\n" \
+ patch_data \
+ " .align\n" \
+ "5:\n" \
+ " .popsection\n" \
+ __VA_ARGS__)
+
+#define early_patch_stub(type, code, pad, patch_data, ...) \
+ __asm__("@ patch stub\n" \
+ "1:\n" \
+ " b 6f\n" \
+ " .fill " __stringify(pad) ", 1, 0\n" \
+ "2:\n" \
+ " .pushsection .runtime.patch.table, \"a\"\n" \
+ "3:\n" \
+ " .word 1b\n" \
+ " .hword (" __stringify(type) ")\n" \
+ " .byte (2b-1b)\n" \
+ " .byte (5f-4f)\n" \
+ "4:\n" \
+ patch_data \
+ " .align\n" \
+ "5:\n" \
+ " .popsection\n" \
+ " .pushsection .runtime.patch.code, \"ax\"\n" \
+ "6:\n" \
+ code \
+ " b 2b\n" \
+ " .popsection\n" \
+ __VA_ARGS__)
+
+/* constant used to force encoding */
+#define __IMM8 (0x81 << 24)
+
+/*
+ * patch_imm8() - init-time specialized binary operation (imm8 operand)
+ * This effectively does: to = from "insn" sym,
+ * where the value of sym is fixed at init-time, and is patched
+ * in as an immediate operand. This value must be
+ * representible as an 8-bit quantity with an optional
+ * rotation.
+ *
+ * The stub code produced by this variant is non-functional
+ * prior to patching. Use early_patch_imm8() if you need the
+ * code to be functional early on in the init sequence.
+ */
+#define patch_imm8(_insn, _to, _from, _sym, _ofs) \
+ patch_stub( \
+ /* type */ \
+ PATCH_IMM8, \
+ /* code */ \
+ _insn " %[to], %[from], %[imm]\n", \
+ /* patch_data */ \
+ ".long " __stringify(_sym + _ofs) "\n" \
+ _insn " %[to], %[from], %[imm]\n", \
+ /* operands */ \
+ : [to] "=r" (_to) \
+ : [from] "r" (_from), \
+ [imm] "I" (__IMM8), \
+ "i" (&(_sym)) \
+ : "cc")
+
+/*
+ * patch_imm8_mov() - same as patch_imm8(), but for mov/mvn instructions
+ */
+#define patch_imm8_mov(_insn, _to, _sym, _ofs) \
+ patch_stub( \
+ /* type */ \
+ PATCH_IMM8, \
+ /* code */ \
+ _insn " %[to], %[imm]\n", \
+ /* patch_data */ \
+ ".long " __stringify(_sym + _ofs) "\n" \
+ _insn " %[to], %[imm]\n", \
+ /* operands */ \
+ : [to] "=r" (_to) \
+ : [imm] "I" (__IMM8), \
+ "i" (&(_sym)) \
+ : "cc")
+
+/*
+ * early_patch_imm8() - early functional variant of patch_imm8() above. The
+ * same restrictions on the constant apply here. This
+ * version emits workable (albeit inefficient) code at
+ * compile-time, and therefore functions even prior to
+ * patch application.
+ */
+#define early_patch_imm8(_insn, _to, _from, _sym, _ofs) \
+do { \
+ unsigned long __tmp; \
+ early_patch_stub( \
+ /* type */ \
+ PATCH_IMM8, \
+ /* code */ \
+ "ldr %[tmp], =" __stringify(_sym + _ofs) "\n"\
+ "ldr %[tmp], [%[tmp]]\n" \
+ _insn " %[to], %[from], %[tmp]\n", \
+ /* pad */ \
+ 0, \
+ /* patch_data */ \
+ ".long " __stringify(_sym + _ofs) "\n" \
+ _insn " %[to], %[from], %[imm]\n", \
+ /* operands */ \
+ : [to] "=r" (_to), \
+ [tmp] "=&r" (__tmp) \
+ : [from] "r" (_from), \
+ [imm] "I" (__IMM8), \
+ "i" (&(_sym)) \
+ : "cc"); \
+} while (0)
+
+#define early_patch_imm8_mov(_insn, _to, _sym, _ofs) \
+do { \
+ unsigned long __tmp; \
+ early_patch_stub( \
+ /* type */ \
+ PATCH_IMM8 \
+ /* code */ \
+ "ldr %[tmp], =" __stringify(_sym + _ofs) "\n"\
+ "ldr %[tmp], [%[tmp]]\n" \
+ _insn " %[to], %[tmp]\n", \
+ /* pad */ \
+ 0, \
+ /* patch_data */ \
+ ".long " __stringify(_sym + _ofs) "\n" \
+ _insn " %[to], %[imm]\n", \
+ /* operands */ \
+ : [to] "=r" (_to), \
+ [tmp] "=&r" (__tmp) \
+ : [imm] "I" (__IMM8), \
+ "i" (&(_sym)) \
+ : "cc"); \
+} while (0)
+
+int runtime_patch(const void *table, unsigned size);
+void runtime_patch_kernel(void);
+
+#else
+
+static inline int runtime_patch(const void *table, unsigned size)
+{
+ return 0;
+}
+
+static inline void runtime_patch_kernel(void)
+{
+}
+
+#endif /* CONFIG_ARM_RUNTIME_PATCH */
+
+#endif /* __ASSEMBLY__ */
+
+#endif /* __ASM_ARM_RUNTIME_PATCH_H */
diff --git a/arch/arm/kernel/Makefile b/arch/arm/kernel/Makefile
index 5bbec7b8183..47868ae4e48 100644
--- a/arch/arm/kernel/Makefile
+++ b/arch/arm/kernel/Makefile
@@ -80,6 +80,7 @@ endif
head-y := head$(MMUEXT).o
obj-$(CONFIG_DEBUG_LL) += debug.o
obj-$(CONFIG_EARLY_PRINTK) += early_printk.o
+obj-$(CONFIG_ARM_RUNTIME_PATCH) += runtime-patch.o patch.o
obj-$(CONFIG_ARM_VIRT_EXT) += hyp-stub.o
diff --git a/arch/arm/kernel/module.c b/arch/arm/kernel/module.c
index 1e9be5d25e5..10a2922220e 100644
--- a/arch/arm/kernel/module.c
+++ b/arch/arm/kernel/module.c
@@ -24,6 +24,7 @@
#include <asm/sections.h>
#include <asm/smp_plat.h>
#include <asm/unwind.h>
+#include <asm/runtime-patch.h>
#ifdef CONFIG_XIP_KERNEL
/*
@@ -276,7 +277,7 @@ int module_finalize(const Elf32_Ehdr *hdr, const Elf_Shdr *sechdrs,
const char *secstrs = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset;
const Elf_Shdr *sechdrs_end = sechdrs + hdr->e_shnum;
struct mod_unwind_map maps[ARM_SEC_MAX];
- int i;
+ int i, err;
memset(maps, 0, sizeof(maps));
@@ -321,6 +322,12 @@ int module_finalize(const Elf32_Ehdr *hdr, const Elf_Shdr *sechdrs,
if (s)
fixup_pv_table((void *)s->sh_addr, s->sh_size);
#endif
+ s = find_mod_section(hdr, sechdrs, ".runtime.patch.table");
+ if (s) {
+ err = runtime_patch((void *)s->sh_addr, s->sh_size);
+ if (err)
+ return err;
+ }
s = find_mod_section(hdr, sechdrs, ".alt.smp.init");
if (s && !is_smp())
#ifdef CONFIG_SMP_ON_UP
diff --git a/arch/arm/kernel/runtime-patch.c b/arch/arm/kernel/runtime-patch.c
new file mode 100644
index 00000000000..28a6367fac0
--- /dev/null
+++ b/arch/arm/kernel/runtime-patch.c
@@ -0,0 +1,193 @@
+/*
+ * arch/arm/kernel/runtime-patch.c
+ *
+ * Copyright 2012 Texas Instruments, Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+#include <linux/kernel.h>
+#include <linux/sched.h>
+
+#include <asm/opcodes.h>
+#include <asm/cacheflush.h>
+#include <asm/runtime-patch.h>
+
+#include "patch.h"
+
+static inline void flush_icache_insn(void *insn_ptr, int bytes)
+{
+ unsigned long insn_addr = (unsigned long)insn_ptr;
+ flush_icache_range(insn_addr, insn_addr + bytes - 1);
+}
+
+#ifdef CONFIG_THUMB2_KERNEL
+
+static int do_patch_imm8(u32 insn, u32 imm, u32 *ninsn)
+{
+ u32 op, rot, val;
+ const u32 supported_ops = (BIT(0) | /* and */
+ BIT(1) | /* bic */
+ BIT(2) | /* orr/mov */
+ BIT(3) | /* orn/mvn */
+ BIT(4) | /* eor */
+ BIT(8) | /* add */
+ BIT(10) | /* adc */
+ BIT(11) | /* sbc */
+ BIT(12) | /* sub */
+ BIT(13)); /* rsb */
+
+ insn = __mem_to_opcode_thumb32(insn);
+
+ if (!__opcode_is_thumb32(insn)) {
+ pr_err("patch: invalid thumb2 insn %08x\n", insn);
+ return -EINVAL;
+ }
+
+ /* allow only data processing (immediate)
+ * 1111 0x0x xxx0 xxxx 0xxx xxxx xxxx xxxx */
+ if ((insn & 0xfa008000) != 0xf0000000) {
+ pr_err("patch: unknown insn %08x\n", insn);
+ return -EINVAL;
+ }
+
+ /* extract op code */
+ op = (insn >> 21) & 0xf;
+
+ /* disallow unsupported opcodes */
+ if ((supported_ops & BIT(op)) == 0) {
+ pr_err("patch: unsupported opcode %x\n", op);
+ return -EINVAL;
+ }
+
+ if (imm <= 0xff) {
+ rot = 0;
+ val = imm;
+ } else {
+ rot = 32 - fls(imm); /* clz */
+ if (imm & ~(0xff000000 >> rot)) {
+ pr_err("patch: constant overflow %08x\n", imm);
+ return -EINVAL;
+ }
+ val = (imm >> (24 - rot)) & 0x7f;
+ rot += 8; /* encoded i:imm3:a */
+
+ /* pack least-sig rot bit into most-sig val bit */
+ val |= (rot & 1) << 7;
+ rot >>= 1;
+ }
+
+ *ninsn = insn & ~(BIT(26) | 0x7 << 12 | 0xff);
+ *ninsn |= (rot >> 3) << 26; /* field "i" */
+ *ninsn |= (rot & 0x7) << 12; /* field "imm3" */
+ *ninsn |= val;
+
+ return 0;
+}
+
+#else
+
+static int do_patch_imm8(u32 insn, u32 imm, u32 *ninsn)
+{
+ u32 rot, val, op;
+
+ insn = __mem_to_opcode_arm(insn);
+
+ /* disallow special unconditional instructions
+ * 1111 xxxx xxxx xxxx xxxx xxxx xxxx xxxx */
+ if ((insn >> 24) == 0xf) {
+ pr_err("patch: unconditional insn %08x\n", insn);
+ return -EINVAL;
+ }
+
+ /* allow only data processing (immediate)
+ * xxxx 001x xxxx xxxx xxxx xxxx xxxx xxxx */
+ if (((insn >> 25) & 0x3) != 1) {
+ pr_err("patch: unknown insn %08x\n", insn);
+ return -EINVAL;
+ }
+
+ /* extract op code */
+ op = (insn >> 20) & 0x1f;
+
+ /* disallow unsupported 10xxx op codes */
+ if (((op >> 3) & 0x3) == 2) {
+ pr_err("patch: unsupported opcode %08x\n", insn);
+ return -EINVAL;
+ }
+
+ rot = imm ? __ffs(imm) / 2 : 0;
+ val = imm >> (rot * 2);
+ rot = (-rot) & 0xf;
+
+ /* does this fit in 8-bit? */
+ if (val > 0xff) {
+ pr_err("patch: constant overflow %08x\n", imm);
+ return -EINVAL;
+ }
+
+ /* patch in new immediate and rotation */
+ *ninsn = (insn & ~0xfff) | (rot << 8) | val;
+
+ return 0;
+}
+
+#endif /* CONFIG_THUMB2_KERNEL */
+
+static int apply_patch_imm8(const struct patch_info *p)
+{
+ u32 *insn_ptr = p->insn, ninsn;
+ int count = p->insn_size / sizeof(u32);
+ const struct patch_info_imm8 *info;
+ int err;
+
+
+ if (count <= 0 || p->data_size != count * sizeof(*info)) {
+ pr_err("patch: bad patch, insn size %d, data size %d\n",
+ p->insn_size, p->data_size);
+ return -EINVAL;
+ }
+
+ for (info = patch_data(p); count; count--, info++, insn_ptr++) {
+ err = do_patch_imm8(info->insn, *info->imm, &ninsn);
+ if (err)
+ return err;
+ __patch_text(insn_ptr, ninsn);
+ }
+
+
+ return 0;
+}
+
+int runtime_patch(const void *table, unsigned size)
+{
+ const struct patch_info *p = table, *end = (table + size);
+
+ for (p = table; p < end; p = patch_next(p)) {
+ int err = -EINVAL;
+
+ if (p->type == PATCH_IMM8)
+ err = apply_patch_imm8(p);
+ if (err)
+ return err;
+ }
+ return 0;
+}
+
+void __init runtime_patch_kernel(void)
+{
+ extern unsigned __runtime_patch_table_begin, __runtime_patch_table_end;
+ const void *start = &__runtime_patch_table_begin;
+ const void *end = &__runtime_patch_table_end;
+
+ BUG_ON(runtime_patch(start, end - start));
+}
diff --git a/arch/arm/kernel/setup.c b/arch/arm/kernel/setup.c
index 3f6cbb2e3ed..125d611917e 100644
--- a/arch/arm/kernel/setup.c
+++ b/arch/arm/kernel/setup.c
@@ -54,6 +54,7 @@
#include <asm/unwind.h>
#include <asm/memblock.h>
#include <asm/virt.h>
+#include <asm/runtime-patch.h>
#include "atags.h"
#include "tcm.h"
@@ -794,6 +795,8 @@ void __init setup_arch(char **cmdline_p)
if (mdesc->init_early)
mdesc->init_early();
+
+ runtime_patch_kernel();
}
diff --git a/arch/arm/kernel/vmlinux.lds.S b/arch/arm/kernel/vmlinux.lds.S
index 11c1785bf63..be885d73997 100644
--- a/arch/arm/kernel/vmlinux.lds.S
+++ b/arch/arm/kernel/vmlinux.lds.S
@@ -178,6 +178,16 @@ SECTIONS
*(.pv_table)
__pv_table_end = .;
}
+ .init.runtime_patch_table : {
+ __runtime_patch_table_begin = .;
+ *(.runtime.patch.table)
+ __runtime_patch_table_end = .;
+ }
+ .init.runtime_patch_code : {
+ __runtime_patch_code_begin = .;
+ *(.runtime.patch.code)
+ __runtime_patch_code_end = .;
+ }
.init.data : {
#ifndef CONFIG_XIP_KERNEL
INIT_DATA
generated by cgit v1.2.3 (git 2.25.1) at 2024-05-13 23:52:34 +0000