From 034dd340b08be1f2f0477ad16131d609f9dbd53c Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Sun, 30 Aug 2026 09:22:00 -0700 Subject: Merge tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace Pull tracing fixes from Steven Rostedt: - Fix error output of boot instance creation failure Currently if a boot instance creation fails, instead of printing out the name of the instance that failed, it prints "(null)". That is because it prints "cur_str" that had already been processed by strsep(). Print the saved name instead. While at it, print the error code of the failure. - Fix use-after-free for same named historgrams Histograms can be named so that they can be used in multiple events. But if the named histogram has a variable attached, the second event that uses the named histogram which duplicates it and needs to free the original after duplication leaves the old variable in place and still visible. If another histogram uses than variable, it will use the stale one which will try to reference the freed duplicate histogram and crash the kernel. Free the duplicate variables along with the duplicated histogram data. - Check return value of kthread_run() in event self test The events self tests uses a kthread for testing but does not check if it succeeded in creating a kthread. If the kthread creation were to fail, the code will still try to call kthread_stop() on the error returned. - Fix race between reading trace_pipe and updating subbuffer size If a user is reading the trace_pipe file at the same time they update the ring buffer sub-buffer size, can cause the trace_pipe read to read stale data. Add trace_access_lock() around updating the ring buffer sub-buffer size. - Fix eventfs_inode on failure path in creation of the events directory In the creation of the "events" directory, if after allocating the eventfs_inode a failure is detected, it calls cleanup_ei() which calls free_ei(). The free_ei() will test if eventfs_inode being freed has no children. It is a bug if it does. But on the failure case of the creation of the "events" directory, the children lists have not yet been initialized and the free will trigger a warning because list_empty() on an uninitialized list returns false. Move the initialization into init_ei() where it makes more sense and makes sure that a created eventfs_inode has its lists initialized upon creation. - Check return value of kthread_run() in ftrace direct sample code The sample code that shows how to use the ftrace direct calls does not test the return of kthread_run() to see if it succeeds. Return a failure if the kthread_run() doesn't succeed. - Clear user events state on fork in case of alloc failure On fork, the child gets a pointer to the parent's user events state. It makes a copy of it then updates the child's pointer to it. But if the allocation fails, the duplication function leaves the child with a pointer to its parent's descriptor. When the child cleans up its data, it will free the parent's descriptor while the parent is still using it. In the duplication function, set the child's user_event_mm to NULL before testing if the allocation succeeded, and when it exits it will not free the parent's descriptor. - Fix retry exhaustion in simple ring buffer reader swap simple_ring_buffer_swap_reader_page() starts with retry set to 8 and post-decrements it only after a failed link replacement. On the final attempt, a successful replacement leaves retry at zero, while a failed replacement leaves it at -1. But the check for success expects the retry value to be non-zero and exits with an error on zero. This is the opposite result. Fix it. - Fail nicely when the remote swap_reader_page() returns an error Currently, if the swap_reader_page() of a remote buffer fails, it triggers a WARN_ON_ONCE() and continues normally. Instead, have it exit with an error and a pr_warn() print instead of a full WARNING. * tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: ring-buffer: Stop remote reader update when page swap fails tracing: Fix retry exhaustion in simple ring buffer reader swap tracing/user_events: Clear copied tracing state before fork duplication samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-multi-modify samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-modify eventfs: Initialize ei->children and ei->list in init_ei() tracing: Fix use-after-free in trace_pipe read on sub-buffer order change tracing: Fix crash passing ERR_PTR to kthread_stop() tracing: Fix use-after-free with same-name named triggers tracing: Fix logged instance name on creation failure --- tools/objtool/arch/powerpc/Build | 2 + tools/objtool/arch/powerpc/decode.c | 153 +++++++++++++++++++++ tools/objtool/arch/powerpc/include/arch/cfi_regs.h | 11 ++ tools/objtool/arch/powerpc/include/arch/elf.h | 13 ++ tools/objtool/arch/powerpc/include/arch/special.h | 21 +++ tools/objtool/arch/powerpc/special.c | 25 ++++ 6 files changed, 225 insertions(+) create mode 100644 tools/objtool/arch/powerpc/Build create mode 100644 tools/objtool/arch/powerpc/decode.c create mode 100644 tools/objtool/arch/powerpc/include/arch/cfi_regs.h create mode 100644 tools/objtool/arch/powerpc/include/arch/elf.h create mode 100644 tools/objtool/arch/powerpc/include/arch/special.h create mode 100644 tools/objtool/arch/powerpc/special.c (limited to 'tools/objtool/arch/powerpc') diff --git a/tools/objtool/arch/powerpc/Build b/tools/objtool/arch/powerpc/Build new file mode 100644 index 000000000..d24d5636a --- /dev/null +++ b/tools/objtool/arch/powerpc/Build @@ -0,0 +1,2 @@ +objtool-y += decode.o +objtool-y += special.o diff --git a/tools/objtool/arch/powerpc/decode.c b/tools/objtool/arch/powerpc/decode.c new file mode 100644 index 000000000..e534ac112 --- /dev/null +++ b/tools/objtool/arch/powerpc/decode.c @@ -0,0 +1,153 @@ +// SPDX-License-Identifier: GPL-2.0-or-later + +#include +#include +#include +#include +#include +#include +#include +#include + +const char *arch_reg_name[CFI_NUM_REGS] = { + "r0", "sp", "r2", "r3", + "r4", "r5", "r6", "r7", + "r8", "r9", "r10", "r11", + "r12", "r13", "r14", "r15", + "r16", "r17", "r18", "r19", + "r20", "r21", "r22", "r23", + "r24", "r25", "r26", "r27", + "r28", "r29", "r30", "r31", + "ra" +}; + +int arch_ftrace_match(const char *name) +{ + return !strcmp(name, "_mcount"); +} + +s64 arch_insn_adjusted_addend(struct instruction *insn, struct reloc *reloc) +{ + return reloc_addend(reloc); +} + +bool arch_callee_saved_reg(unsigned char reg) +{ + return false; +} + +int arch_decode_hint_reg(u8 sp_reg, int *base) +{ + exit(-1); +} + +const char *arch_nop_insn(int len) +{ + exit(-1); +} + +const char *arch_ret_insn(int len) +{ + exit(-1); +} + +int arch_decode_instruction(struct objtool_file *file, const struct section *sec, + unsigned long offset, unsigned int maxlen, + struct instruction *insn) +{ + unsigned int opcode; + enum insn_type typ; + unsigned long imm; + u32 ins; + + ins = bswap_if_needed(file->elf, *(u32 *)(sec->data->d_buf + offset)); + opcode = ins >> 26; + typ = INSN_OTHER; + imm = 0; + + switch (opcode) { + case 18: /* b[l][a] */ + if (ins == 0x48000005) /* bl .+4 */ + typ = INSN_OTHER; + else if (ins & 1) /* bl[a] */ + typ = INSN_CALL; + else /* b[a] */ + typ = INSN_JUMP_UNCONDITIONAL; + + imm = ins & 0x3fffffc; + if (imm & 0x2000000) + imm -= 0x4000000; + imm |= ins & 2; /* AA flag */ + break; + } + + if (opcode == 1) + insn->len = 8; + else + insn->len = 4; + + insn->type = typ; + insn->immediate = imm; + + return 0; +} + +unsigned long arch_jump_destination(struct instruction *insn) +{ + if (insn->immediate & 2) + return insn->immediate & ~2; + + return insn->offset + insn->immediate; +} + +bool arch_pc_relative_reloc(struct reloc *reloc) +{ + /* + * The powerpc build only allows certain relocation types, see + * relocs_check.sh, and none of those accepted are PC relative. + */ + return false; +} + +void arch_initial_func_cfi_state(struct cfi_init_state *state) +{ + int i; + + for (i = 0; i < CFI_NUM_REGS; i++) { + state->regs[i].base = CFI_UNDEFINED; + state->regs[i].offset = 0; + } + + /* initial CFA (call frame address) */ + state->cfa.base = CFI_SP; + state->cfa.offset = 0; + + /* initial LR (return address) */ + state->regs[CFI_RA].base = CFI_CFA; + state->regs[CFI_RA].offset = 0; +} + +unsigned int arch_reloc_size(struct reloc *reloc) +{ + switch (reloc_type(reloc)) { + case R_PPC_REL32: + case R_PPC_ADDR32: + case R_PPC_UADDR32: + case R_PPC_PLT32: + case R_PPC_PLTREL32: + return 4; + default: + return 8; + } +} + +#ifdef DISAS + +int arch_disas_info_init(struct disassemble_info *dinfo) +{ + return disas_info_init(dinfo, bfd_arch_powerpc, + bfd_mach_ppc, bfd_mach_ppc64, + NULL); +} + +#endif /* DISAS */ diff --git a/tools/objtool/arch/powerpc/include/arch/cfi_regs.h b/tools/objtool/arch/powerpc/include/arch/cfi_regs.h new file mode 100644 index 000000000..59638ebea --- /dev/null +++ b/tools/objtool/arch/powerpc/include/arch/cfi_regs.h @@ -0,0 +1,11 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ + +#ifndef _OBJTOOL_CFI_REGS_H +#define _OBJTOOL_CFI_REGS_H + +#define CFI_BP 1 +#define CFI_SP CFI_BP +#define CFI_RA 32 +#define CFI_NUM_REGS 33 + +#endif diff --git a/tools/objtool/arch/powerpc/include/arch/elf.h b/tools/objtool/arch/powerpc/include/arch/elf.h new file mode 100644 index 000000000..66814fa28 --- /dev/null +++ b/tools/objtool/arch/powerpc/include/arch/elf.h @@ -0,0 +1,13 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +#ifndef _OBJTOOL_ARCH_ELF +#define _OBJTOOL_ARCH_ELF + +#define R_NONE R_PPC_NONE +#define R_ABS64 R_PPC64_ADDR64 +#define R_ABS32 R_PPC_ADDR32 +#define R_DATA32 R_PPC_REL32 +#define R_DATA64 R_PPC64_REL64 +#define R_TEXT32 R_PPC_REL32 +#define R_TEXT64 R_PPC64_REL32 + +#endif /* _OBJTOOL_ARCH_ELF */ diff --git a/tools/objtool/arch/powerpc/include/arch/special.h b/tools/objtool/arch/powerpc/include/arch/special.h new file mode 100644 index 000000000..ffef9ada7 --- /dev/null +++ b/tools/objtool/arch/powerpc/include/arch/special.h @@ -0,0 +1,21 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +#ifndef _PPC_ARCH_SPECIAL_H +#define _PPC_ARCH_SPECIAL_H + +#define EX_ENTRY_SIZE 8 +#define EX_ORIG_OFFSET 0 +#define EX_NEW_OFFSET 4 + +#define JUMP_ENTRY_SIZE 16 +#define JUMP_ORIG_OFFSET 0 +#define JUMP_NEW_OFFSET 4 +#define JUMP_KEY_OFFSET 8 + +#define ALT_ENTRY_SIZE 12 +#define ALT_ORIG_OFFSET 0 +#define ALT_NEW_OFFSET 4 +#define ALT_FEATURE_OFFSET 8 +#define ALT_ORIG_LEN_OFFSET 10 +#define ALT_NEW_LEN_OFFSET 11 + +#endif /* _PPC_ARCH_SPECIAL_H */ diff --git a/tools/objtool/arch/powerpc/special.c b/tools/objtool/arch/powerpc/special.c new file mode 100644 index 000000000..8f9bf61ca --- /dev/null +++ b/tools/objtool/arch/powerpc/special.c @@ -0,0 +1,25 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +#include +#include +#include +#include + + +bool arch_support_alt_relocation(struct special_alt *special_alt, + struct instruction *insn, + struct reloc *reloc) +{ + exit(-1); +} + +struct reloc *arch_find_switch_table(struct objtool_file *file, + struct instruction *insn, + unsigned long *table_size) +{ + exit(-1); +} + +const char *arch_cpu_feature_name(int feature_number) +{ + return NULL; +} -- cgit v1.3.1