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authorLinus Torvalds <torvalds@linux-foundation.org>2026-08-23 13:28:57 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-08-23 13:28:57 -0700
commit4352b8aee98005853aa63f57d6377282de17a33f (patch)
tree27614d7a9ef05c32d089004e104364ce42324837 /arch/powerpc/lib/test-code-patching.c
downloadlinux-stable-4352b8aee98005853aa63f57d6377282de17a33f.tar.gz
linux-stable-4352b8aee98005853aa63f57d6377282de17a33f.zip
Merge tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linuxgrafted
Pull I3C updates from Alexandre Belloni: "A new driver this cycle, for the AMD AXI I3C controller. There are also new features such as IBI wakeup support, SETAASA device discovery and ACPI support for the the DAA methods, meaning we can now communicate with the SPD devices on DDR5 modules. New driver: - AMD AXI I3C master controller Subsystem: - I3C Common Command Code (CCC) handling improvements, especially around GET CCCs - SETAASA device discovery support - ACPI support for all existing DAA methods like SETDASA, SETNEWDA as well as I2C devices on I3C bus - IBI-based wakeup support Drivers: - dw: SETAASA support - mipi-i3c-hci: advertise IBI wakeup capability, AMD_PT I3C controller support, PIO queue management support for HCI v1.2 - renesas: improve suspend to RAM support, add runtime PM support" * tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux: (70 commits) i3c: dw: reduce do_daa time if there's no client i3c: mipi-i3c-hci: Add support for AMD_PT I3C controller i3c: mipi-i3c-hci: Add PIO queue management support for HCI v1.2 i3c: mipi-i3c-hci: Fix missing STAT_IBI_STATUS_THLD in PIO mode i3c: dw: rename "pclk" to "apb" to match dt-binding i3c: dw: make struct dw_i3c_cmd smaller i3c: dw: use COMMAND_PORT_TRANSFER_ARG instead of hardcoding i3c: renesas: Don't register devices when ENTDAA times out i3c: master: dw-i3c-master: fix OD timing for first broadcast i3c: mipi-i3c-hci: Advertise IBI wakeup capability i3c: mipi-i3c-hci: Factor out i3c_hci_sysdev() i3c: mipi-i3c-hci-pci: Propagate I3C wakeup requirements to PCI i3c: master: Reject IBI requests from non-IBI-capable devices i3c: master: Add helper to query bus wakeup requirements i3c: master: Report wakeup events for IBIs i3c: master: Support IBI-based wakeup capability i3c: master: Fix potential UAF in i3c_device_match() i3c: master: Fix potential UAF in i3c_device_uevent() i3c: Make dev->desc locking assumptions explicit i3c: master: Fix use-after-free of master->this ...
Diffstat (limited to 'arch/powerpc/lib/test-code-patching.c')
-rw-r--r--arch/powerpc/lib/test-code-patching.c495
1 files changed, 495 insertions, 0 deletions
diff --git a/arch/powerpc/lib/test-code-patching.c b/arch/powerpc/lib/test-code-patching.c
new file mode 100644
index 000000000..1440d9963
--- /dev/null
+++ b/arch/powerpc/lib/test-code-patching.c
@@ -0,0 +1,495 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright 2008 Michael Ellerman, IBM Corporation.
+ */
+
+#include <linux/vmalloc.h>
+#include <linux/init.h>
+
+#include <asm/text-patching.h>
+
+static int __init instr_is_branch_to_addr(const u32 *instr, unsigned long addr)
+{
+ if (instr_is_branch_iform(ppc_inst_read(instr)) ||
+ instr_is_branch_bform(ppc_inst_read(instr)))
+ return branch_target(instr) == addr;
+
+ return 0;
+}
+
+static void __init test_trampoline(void)
+{
+ asm ("nop;nop;\n");
+}
+
+#define check(x) do { \
+ if (!(x)) \
+ pr_err("code-patching: test failed at line %d\n", __LINE__); \
+} while (0)
+
+static void __init test_branch_iform(void)
+{
+ int err;
+ ppc_inst_t instr;
+ u32 tmp[2];
+ u32 *iptr = tmp;
+ unsigned long addr = (unsigned long)tmp;
+
+ /* The simplest case, branch to self, no flags */
+ check(instr_is_branch_iform(ppc_inst(0x48000000)));
+ /* All bits of target set, and flags */
+ check(instr_is_branch_iform(ppc_inst(0x4bffffff)));
+ /* High bit of opcode set, which is wrong */
+ check(!instr_is_branch_iform(ppc_inst(0xcbffffff)));
+ /* Middle bits of opcode set, which is wrong */
+ check(!instr_is_branch_iform(ppc_inst(0x7bffffff)));
+
+ /* Simplest case, branch to self with link */
+ check(instr_is_branch_iform(ppc_inst(0x48000001)));
+ /* All bits of targets set */
+ check(instr_is_branch_iform(ppc_inst(0x4bfffffd)));
+ /* Some bits of targets set */
+ check(instr_is_branch_iform(ppc_inst(0x4bff00fd)));
+ /* Must be a valid branch to start with */
+ check(!instr_is_branch_iform(ppc_inst(0x7bfffffd)));
+
+ /* Absolute branch to 0x100 */
+ ppc_inst_write(iptr, ppc_inst(0x48000103));
+ check(instr_is_branch_to_addr(iptr, 0x100));
+ /* Absolute branch to 0x420fc */
+ ppc_inst_write(iptr, ppc_inst(0x480420ff));
+ check(instr_is_branch_to_addr(iptr, 0x420fc));
+ /* Maximum positive relative branch, + 20MB - 4B */
+ ppc_inst_write(iptr, ppc_inst(0x49fffffc));
+ check(instr_is_branch_to_addr(iptr, addr + 0x1FFFFFC));
+ /* Smallest negative relative branch, - 4B */
+ ppc_inst_write(iptr, ppc_inst(0x4bfffffc));
+ check(instr_is_branch_to_addr(iptr, addr - 4));
+ /* Largest negative relative branch, - 32 MB */
+ ppc_inst_write(iptr, ppc_inst(0x4a000000));
+ check(instr_is_branch_to_addr(iptr, addr - 0x2000000));
+
+ /* Branch to self, with link */
+ err = create_branch(&instr, iptr, addr, BRANCH_SET_LINK);
+ ppc_inst_write(iptr, instr);
+ check(instr_is_branch_to_addr(iptr, addr));
+
+ /* Branch to self - 0x100, with link */
+ err = create_branch(&instr, iptr, addr - 0x100, BRANCH_SET_LINK);
+ ppc_inst_write(iptr, instr);
+ check(instr_is_branch_to_addr(iptr, addr - 0x100));
+
+ /* Branch to self + 0x100, no link */
+ err = create_branch(&instr, iptr, addr + 0x100, 0);
+ ppc_inst_write(iptr, instr);
+ check(instr_is_branch_to_addr(iptr, addr + 0x100));
+
+ /* Maximum relative negative offset, - 32 MB */
+ err = create_branch(&instr, iptr, addr - 0x2000000, BRANCH_SET_LINK);
+ ppc_inst_write(iptr, instr);
+ check(instr_is_branch_to_addr(iptr, addr - 0x2000000));
+
+ /* Out of range relative negative offset, - 32 MB + 4*/
+ err = create_branch(&instr, iptr, addr - 0x2000004, BRANCH_SET_LINK);
+ check(err);
+
+ /* Out of range relative positive offset, + 32 MB */
+ err = create_branch(&instr, iptr, addr + 0x2000000, BRANCH_SET_LINK);
+ check(err);
+
+ /* Unaligned target */
+ err = create_branch(&instr, iptr, addr + 3, BRANCH_SET_LINK);
+ check(err);
+
+ /* Check flags are masked correctly */
+ err = create_branch(&instr, iptr, addr, 0xFFFFFFFC);
+ ppc_inst_write(iptr, instr);
+ check(instr_is_branch_to_addr(iptr, addr));
+ check(ppc_inst_equal(instr, ppc_inst(0x48000000)));
+}
+
+static void __init test_create_function_call(void)
+{
+ u32 *iptr;
+ unsigned long dest;
+ ppc_inst_t instr;
+
+ /* Check we can create a function call */
+ iptr = (u32 *)ppc_function_entry(test_trampoline);
+ dest = ppc_function_entry(test_create_function_call);
+ create_branch(&instr, iptr, dest, BRANCH_SET_LINK);
+ patch_instruction(iptr, instr);
+ check(instr_is_branch_to_addr(iptr, dest));
+}
+
+static void __init test_branch_bform(void)
+{
+ int err;
+ unsigned long addr;
+ ppc_inst_t instr;
+ u32 tmp[2];
+ u32 *iptr = tmp;
+ unsigned int flags;
+
+ addr = (unsigned long)iptr;
+
+ /* The simplest case, branch to self, no flags */
+ check(instr_is_branch_bform(ppc_inst(0x40000000)));
+ /* All bits of target set, and flags */
+ check(instr_is_branch_bform(ppc_inst(0x43ffffff)));
+ /* High bit of opcode set, which is wrong */
+ check(!instr_is_branch_bform(ppc_inst(0xc3ffffff)));
+ /* Middle bits of opcode set, which is wrong */
+ check(!instr_is_branch_bform(ppc_inst(0x7bffffff)));
+
+ /* Absolute conditional branch to 0x100 */
+ ppc_inst_write(iptr, ppc_inst(0x43ff0103));
+ check(instr_is_branch_to_addr(iptr, 0x100));
+ /* Absolute conditional branch to 0x20fc */
+ ppc_inst_write(iptr, ppc_inst(0x43ff20ff));
+ check(instr_is_branch_to_addr(iptr, 0x20fc));
+ /* Maximum positive relative conditional branch, + 32 KB - 4B */
+ ppc_inst_write(iptr, ppc_inst(0x43ff7ffc));
+ check(instr_is_branch_to_addr(iptr, addr + 0x7FFC));
+ /* Smallest negative relative conditional branch, - 4B */
+ ppc_inst_write(iptr, ppc_inst(0x43fffffc));
+ check(instr_is_branch_to_addr(iptr, addr - 4));
+ /* Largest negative relative conditional branch, - 32 KB */
+ ppc_inst_write(iptr, ppc_inst(0x43ff8000));
+ check(instr_is_branch_to_addr(iptr, addr - 0x8000));
+
+ /* All condition code bits set & link */
+ flags = 0x3ff000 | BRANCH_SET_LINK;
+
+ /* Branch to self */
+ err = create_cond_branch(&instr, iptr, addr, flags);
+ ppc_inst_write(iptr, instr);
+ check(instr_is_branch_to_addr(iptr, addr));
+
+ /* Branch to self - 0x100 */
+ err = create_cond_branch(&instr, iptr, addr - 0x100, flags);
+ ppc_inst_write(iptr, instr);
+ check(instr_is_branch_to_addr(iptr, addr - 0x100));
+
+ /* Branch to self + 0x100 */
+ err = create_cond_branch(&instr, iptr, addr + 0x100, flags);
+ ppc_inst_write(iptr, instr);
+ check(instr_is_branch_to_addr(iptr, addr + 0x100));
+
+ /* Maximum relative negative offset, - 32 KB */
+ err = create_cond_branch(&instr, iptr, addr - 0x8000, flags);
+ ppc_inst_write(iptr, instr);
+ check(instr_is_branch_to_addr(iptr, addr - 0x8000));
+
+ /* Out of range relative negative offset, - 32 KB + 4*/
+ err = create_cond_branch(&instr, iptr, addr - 0x8004, flags);
+ check(err);
+
+ /* Out of range relative positive offset, + 32 KB */
+ err = create_cond_branch(&instr, iptr, addr + 0x8000, flags);
+ check(err);
+
+ /* Unaligned target */
+ err = create_cond_branch(&instr, iptr, addr + 3, flags);
+ check(err);
+
+ /* Check flags are masked correctly */
+ err = create_cond_branch(&instr, iptr, addr, 0xFFFFFFFC);
+ ppc_inst_write(iptr, instr);
+ check(instr_is_branch_to_addr(iptr, addr));
+ check(ppc_inst_equal(instr, ppc_inst(0x43FF0000)));
+}
+
+static void __init test_translate_branch(void)
+{
+ unsigned long addr;
+ void *p, *q;
+ ppc_inst_t instr;
+ void *buf;
+
+ buf = vmalloc(PAGE_ALIGN(0x2000000 + 1));
+ check(buf);
+ if (!buf)
+ return;
+
+ /* Simple case, branch to self moved a little */
+ p = buf;
+ addr = (unsigned long)p;
+ create_branch(&instr, p, addr, 0);
+ ppc_inst_write(p, instr);
+ check(instr_is_branch_to_addr(p, addr));
+ q = p + 4;
+ translate_branch(&instr, q, p);
+ ppc_inst_write(q, instr);
+ check(instr_is_branch_to_addr(q, addr));
+
+ /* Maximum negative case, move b . to addr + 32 MB */
+ p = buf;
+ addr = (unsigned long)p;
+ create_branch(&instr, p, addr, 0);
+ ppc_inst_write(p, instr);
+ q = buf + 0x2000000;
+ translate_branch(&instr, q, p);
+ ppc_inst_write(q, instr);
+ check(instr_is_branch_to_addr(p, addr));
+ check(instr_is_branch_to_addr(q, addr));
+ check(ppc_inst_equal(ppc_inst_read(q), ppc_inst(0x4a000000)));
+
+ /* Maximum positive case, move x to x - 32 MB + 4 */
+ p = buf + 0x2000000;
+ addr = (unsigned long)p;
+ create_branch(&instr, p, addr, 0);
+ ppc_inst_write(p, instr);
+ q = buf + 4;
+ translate_branch(&instr, q, p);
+ ppc_inst_write(q, instr);
+ check(instr_is_branch_to_addr(p, addr));
+ check(instr_is_branch_to_addr(q, addr));
+ check(ppc_inst_equal(ppc_inst_read(q), ppc_inst(0x49fffffc)));
+
+ /* Jump to x + 16 MB moved to x + 20 MB */
+ p = buf;
+ addr = 0x1000000 + (unsigned long)buf;
+ create_branch(&instr, p, addr, BRANCH_SET_LINK);
+ ppc_inst_write(p, instr);
+ q = buf + 0x1400000;
+ translate_branch(&instr, q, p);
+ ppc_inst_write(q, instr);
+ check(instr_is_branch_to_addr(p, addr));
+ check(instr_is_branch_to_addr(q, addr));
+
+ /* Jump to x + 16 MB moved to x - 16 MB + 4 */
+ p = buf + 0x1000000;
+ addr = 0x2000000 + (unsigned long)buf;
+ create_branch(&instr, p, addr, 0);
+ ppc_inst_write(p, instr);
+ q = buf + 4;
+ translate_branch(&instr, q, p);
+ ppc_inst_write(q, instr);
+ check(instr_is_branch_to_addr(p, addr));
+ check(instr_is_branch_to_addr(q, addr));
+
+
+ /* Conditional branch tests */
+
+ /* Simple case, branch to self moved a little */
+ p = buf;
+ addr = (unsigned long)p;
+ create_cond_branch(&instr, p, addr, 0);
+ ppc_inst_write(p, instr);
+ check(instr_is_branch_to_addr(p, addr));
+ q = buf + 4;
+ translate_branch(&instr, q, p);
+ ppc_inst_write(q, instr);
+ check(instr_is_branch_to_addr(q, addr));
+
+ /* Maximum negative case, move b . to addr + 32 KB */
+ p = buf;
+ addr = (unsigned long)p;
+ create_cond_branch(&instr, p, addr, 0xFFFFFFFC);
+ ppc_inst_write(p, instr);
+ q = buf + 0x8000;
+ translate_branch(&instr, q, p);
+ ppc_inst_write(q, instr);
+ check(instr_is_branch_to_addr(p, addr));
+ check(instr_is_branch_to_addr(q, addr));
+ check(ppc_inst_equal(ppc_inst_read(q), ppc_inst(0x43ff8000)));
+
+ /* Maximum positive case, move x to x - 32 KB + 4 */
+ p = buf + 0x8000;
+ addr = (unsigned long)p;
+ create_cond_branch(&instr, p, addr, 0xFFFFFFFC);
+ ppc_inst_write(p, instr);
+ q = buf + 4;
+ translate_branch(&instr, q, p);
+ ppc_inst_write(q, instr);
+ check(instr_is_branch_to_addr(p, addr));
+ check(instr_is_branch_to_addr(q, addr));
+ check(ppc_inst_equal(ppc_inst_read(q), ppc_inst(0x43ff7ffc)));
+
+ /* Jump to x + 12 KB moved to x + 20 KB */
+ p = buf;
+ addr = 0x3000 + (unsigned long)buf;
+ create_cond_branch(&instr, p, addr, BRANCH_SET_LINK);
+ ppc_inst_write(p, instr);
+ q = buf + 0x5000;
+ translate_branch(&instr, q, p);
+ ppc_inst_write(q, instr);
+ check(instr_is_branch_to_addr(p, addr));
+ check(instr_is_branch_to_addr(q, addr));
+
+ /* Jump to x + 8 KB moved to x - 8 KB + 4 */
+ p = buf + 0x2000;
+ addr = 0x4000 + (unsigned long)buf;
+ create_cond_branch(&instr, p, addr, 0);
+ ppc_inst_write(p, instr);
+ q = buf + 4;
+ translate_branch(&instr, q, p);
+ ppc_inst_write(q, instr);
+ check(instr_is_branch_to_addr(p, addr));
+ check(instr_is_branch_to_addr(q, addr));
+
+ /* Free the buffer we were using */
+ vfree(buf);
+}
+
+static void __init test_prefixed_patching(void)
+{
+ u32 *iptr = (u32 *)ppc_function_entry(test_trampoline);
+ u32 expected[2] = {OP_PREFIX << 26, 0};
+ ppc_inst_t inst = ppc_inst_prefix(OP_PREFIX << 26, 0);
+
+ if (!IS_ENABLED(CONFIG_PPC64))
+ return;
+
+ patch_instruction(iptr, inst);
+
+ check(!memcmp(iptr, expected, sizeof(expected)));
+}
+
+static void __init test_multi_instruction_patching(void)
+{
+ u32 code[32];
+ void *buf;
+ u32 *addr32;
+ u64 *addr64;
+ ppc_inst_t inst64 = ppc_inst_prefix(OP_PREFIX << 26 | 3UL << 24, PPC_RAW_TRAP());
+ u32 inst32 = PPC_RAW_NOP();
+
+ buf = vzalloc(PAGE_SIZE * 8);
+ check(buf);
+ if (!buf)
+ return;
+
+ /* Test single page 32-bit repeated instruction */
+ addr32 = buf + PAGE_SIZE;
+ check(!patch_instructions(addr32 + 1, &inst32, 12, true));
+
+ check(addr32[0] == 0);
+ check(addr32[1] == inst32);
+ check(addr32[2] == inst32);
+ check(addr32[3] == inst32);
+ check(addr32[4] == 0);
+
+ /* Test single page 64-bit repeated instruction */
+ if (IS_ENABLED(CONFIG_PPC64)) {
+ check(ppc_inst_prefixed(inst64));
+
+ addr64 = buf + PAGE_SIZE * 2;
+ ppc_inst_write(code, inst64);
+ check(!patch_instructions((u32 *)(addr64 + 1), code, 24, true));
+
+ check(addr64[0] == 0);
+ check(ppc_inst_equal(ppc_inst_read((u32 *)&addr64[1]), inst64));
+ check(ppc_inst_equal(ppc_inst_read((u32 *)&addr64[2]), inst64));
+ check(ppc_inst_equal(ppc_inst_read((u32 *)&addr64[3]), inst64));
+ check(addr64[4] == 0);
+ }
+
+ /* Test single page memcpy */
+ addr32 = buf + PAGE_SIZE * 3;
+
+ for (int i = 0; i < ARRAY_SIZE(code); i++)
+ code[i] = i + 1;
+
+ check(!patch_instructions(addr32 + 1, code, sizeof(code), false));
+
+ check(addr32[0] == 0);
+ check(!memcmp(&addr32[1], code, sizeof(code)));
+ check(addr32[ARRAY_SIZE(code) + 1] == 0);
+
+ /* Test multipage 32-bit repeated instruction */
+ addr32 = buf + PAGE_SIZE * 4 - 8;
+ check(!patch_instructions(addr32 + 1, &inst32, 12, true));
+
+ check(addr32[0] == 0);
+ check(addr32[1] == inst32);
+ check(addr32[2] == inst32);
+ check(addr32[3] == inst32);
+ check(addr32[4] == 0);
+
+ /* Test multipage 64-bit repeated instruction */
+ if (IS_ENABLED(CONFIG_PPC64)) {
+ check(ppc_inst_prefixed(inst64));
+
+ addr64 = buf + PAGE_SIZE * 5 - 8;
+ ppc_inst_write(code, inst64);
+ check(!patch_instructions((u32 *)(addr64 + 1), code, 24, true));
+
+ check(addr64[0] == 0);
+ check(ppc_inst_equal(ppc_inst_read((u32 *)&addr64[1]), inst64));
+ check(ppc_inst_equal(ppc_inst_read((u32 *)&addr64[2]), inst64));
+ check(ppc_inst_equal(ppc_inst_read((u32 *)&addr64[3]), inst64));
+ check(addr64[4] == 0);
+ }
+
+ /* Test multipage memcpy */
+ addr32 = buf + PAGE_SIZE * 6 - 12;
+
+ for (int i = 0; i < ARRAY_SIZE(code); i++)
+ code[i] = i + 1;
+
+ check(!patch_instructions(addr32 + 1, code, sizeof(code), false));
+
+ check(addr32[0] == 0);
+ check(!memcmp(&addr32[1], code, sizeof(code)));
+ check(addr32[ARRAY_SIZE(code) + 1] == 0);
+
+ vfree(buf);
+}
+
+static void __init test_data_patching(void)
+{
+ void *buf;
+ u32 *addr32;
+
+ buf = vzalloc(PAGE_SIZE);
+ check(buf);
+ if (!buf)
+ return;
+
+ addr32 = buf + 128;
+
+ addr32[1] = 0xA0A1A2A3;
+ addr32[2] = 0xB0B1B2B3;
+
+ check(!patch_uint(&addr32[1], 0xC0C1C2C3));
+
+ check(addr32[0] == 0);
+ check(addr32[1] == 0xC0C1C2C3);
+ check(addr32[2] == 0xB0B1B2B3);
+ check(addr32[3] == 0);
+
+ /* Unaligned patch_ulong() should fail */
+ if (IS_ENABLED(CONFIG_PPC64))
+ check(patch_ulong(&addr32[1], 0xD0D1D2D3) == -EINVAL);
+
+ check(!patch_ulong(&addr32[2], 0xD0D1D2D3));
+
+ check(addr32[0] == 0);
+ check(addr32[1] == 0xC0C1C2C3);
+ check(*(unsigned long *)(&addr32[2]) == 0xD0D1D2D3);
+
+ if (!IS_ENABLED(CONFIG_PPC64))
+ check(addr32[3] == 0);
+
+ check(addr32[4] == 0);
+
+ vfree(buf);
+}
+
+static int __init test_code_patching(void)
+{
+ pr_info("Running code patching self-tests ...\n");
+
+ test_branch_iform();
+ test_branch_bform();
+ test_create_function_call();
+ test_translate_branch();
+ test_prefixed_patching();
+ test_multi_instruction_patching();
+ test_data_patching();
+
+ return 0;
+}
+late_initcall(test_code_patching);