| Message ID | 20230202074036.507249-6-madvenka@linux.microsoft.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | arm64: livepatch: Use ORC for dynamic frame pointer validation | expand |
On Thu, 2023-02-02 at 01:40 -0600, madvenka@linux.microsoft.com wrote: > From: "Madhavan T. Venkataraman" <madvenka@linux.microsoft.com> > > The ORC code needs to be reorganized into arch-specific and generic > parts > so that architectures other than X86 can use the generic parts. > > orc_types.h contains the following ORC definitions shared between > objtool > and the kernel: > > - ORC register definitions which are arch-specific. > - orc_entry structure which is generic. > > Move orc_entry into a new file include/linux/orc_entry.h. Also, the > field > names bp_reg and bp_offset in struct orc_entry are x86-specific. > Change > them to fp_reg and fp_offset. FP stands for frame pointer. > > Currently, the type field in orc_entry is only 2 bits. For other > architectures, we will need more. So, expand this to 3 bits. > > Signed-off-by: Madhavan T. Venkataraman <madvenka@linux.microsoft.com > > > --- > arch/x86/include/asm/orc_types.h | 37 +++++------------------- > include/linux/orc_entry.h | 39 > ++++++++++++++++++++++++++ > tools/arch/x86/include/asm/orc_types.h | 37 +++++------------------- > tools/include/linux/orc_entry.h | 39 > ++++++++++++++++++++++++++ > tools/objtool/orc_gen.c | 4 +-- > tools/objtool/sync-check.sh | 1 + > 6 files changed, 95 insertions(+), 62 deletions(-) > create mode 100644 include/linux/orc_entry.h > create mode 100644 tools/include/linux/orc_entry.h > [snip] > diff --git a/tools/include/linux/orc_entry.h > b/tools/include/linux/orc_entry.h > new file mode 100644 > index 000000000000..3d49e3b9dabe > --- /dev/null > +++ b/tools/include/linux/orc_entry.h > @@ -0,0 +1,39 @@ > +/* SPDX-License-Identifier: GPL-2.0-or-later */ > +/* > + * Copyright (C) 2017 Josh Poimboeuf <jpoimboe@redhat.com> > + */ > + > +#ifndef _ORC_ENTRY_H > +#define _ORC_ENTRY_H > + > +#ifndef __ASSEMBLY__ > +#include <asm/byteorder.h> > + > +/* > + * This struct is more or less a vastly simplified version of the > DWARF Call > + * Frame Information standard. It contains only the necessary parts > of DWARF > + * CFI, simplified for ease of access by the in-kernel unwinder. It > tells the > + * unwinder how to find the previous SP and BP (and sometimes entry > regs) on > + * the stack for a given code address. Each instance of the struct > corresponds > + * to one or more code locations. > + */ > +struct orc_entry { > + s16 sp_offset; > + s16 fp_offset; > +#if defined(__LITTLE_ENDIAN_BITFIELD) > + unsigned sp_reg:4; > + unsigned fp_reg:4; > + unsigned type:3; > + unsigned end:1; > +#elif defined(__BIG_ENDIAN_BITFIELD) > + unsigned fp_reg:4; > + unsigned sp_reg:4; > + unsigned unused:4; > + unsigned end:1; > + unsigned type:3; > +# nit: I believe you also need to update fp_reg/bp_offset -> fp_reg/fp_offset in orc_dump() in orc_dump.c - Suraj > + > +#endif /* __ASSEMBLY__ */ > + > +#endif /* _ORC_ENTRY_H */ > diff --git a/tools/objtool/orc_gen.c b/tools/objtool/orc_gen.c > index dd3c64af9db2..68c317daadbf 100644 > --- a/tools/objtool/orc_gen.c > +++ b/tools/objtool/orc_gen.c > @@ -98,7 +98,7 @@ static int write_orc_entry(struct elf *elf, struct > section *orc_sec, > orc = (struct orc_entry *)orc_sec->data->d_buf + idx; > memcpy(orc, o, sizeof(*orc)); > orc->sp_offset = bswap_if_needed(orc->sp_offset); > - orc->bp_offset = bswap_if_needed(orc->bp_offset); > + orc->fp_offset = bswap_if_needed(orc->fp_offset); > > /* populate reloc for ip */ > if (elf_add_reloc_to_insn(elf, ip_sec, idx * sizeof(int), > R_X86_64_PC32, > @@ -149,7 +149,7 @@ int orc_create(struct objtool_file *file) > > struct orc_entry null = { > .sp_reg = ORC_REG_UNDEFINED, > - .bp_reg = ORC_REG_UNDEFINED, > + .fp_reg = ORC_REG_UNDEFINED, > .type = UNWIND_HINT_TYPE_CALL, > }; > > diff --git a/tools/objtool/sync-check.sh b/tools/objtool/sync- > check.sh > index ee49b4e9e72c..ef1acb064605 100755 > --- a/tools/objtool/sync-check.sh > +++ b/tools/objtool/sync-check.sh > @@ -18,6 +18,7 @@ arch/x86/include/asm/unwind_hints.h > arch/x86/lib/x86-opcode-map.txt > arch/x86/tools/gen-insn-attr-x86.awk > include/linux/static_call_types.h > +include/linux/orc_entry.h > " > > SYNC_CHECK_FILES='
Sorry for the delay in responding to your comments. I was out sick. Please find my responses inline. On 2/18/23 03:30, Suraj Jitindar Singh wrote: > On Thu, 2023-02-02 at 01:40 -0600, madvenka@linux.microsoft.com wrote: >> From: "Madhavan T. Venkataraman" <madvenka@linux.microsoft.com> >> >> The ORC code needs to be reorganized into arch-specific and generic >> parts >> so that architectures other than X86 can use the generic parts. >> >> orc_types.h contains the following ORC definitions shared between >> objtool >> and the kernel: >> >> - ORC register definitions which are arch-specific. >> - orc_entry structure which is generic. >> >> Move orc_entry into a new file include/linux/orc_entry.h. Also, the >> field >> names bp_reg and bp_offset in struct orc_entry are x86-specific. >> Change >> them to fp_reg and fp_offset. FP stands for frame pointer. >> >> Currently, the type field in orc_entry is only 2 bits. For other >> architectures, we will need more. So, expand this to 3 bits. >> >> Signed-off-by: Madhavan T. Venkataraman <madvenka@linux.microsoft.com >>> >> --- >> arch/x86/include/asm/orc_types.h | 37 +++++------------------- >> include/linux/orc_entry.h | 39 >> ++++++++++++++++++++++++++ >> tools/arch/x86/include/asm/orc_types.h | 37 +++++------------------- >> tools/include/linux/orc_entry.h | 39 >> ++++++++++++++++++++++++++ >> tools/objtool/orc_gen.c | 4 +-- >> tools/objtool/sync-check.sh | 1 + >> 6 files changed, 95 insertions(+), 62 deletions(-) >> create mode 100644 include/linux/orc_entry.h >> create mode 100644 tools/include/linux/orc_entry.h >> > > [snip] > >> diff --git a/tools/include/linux/orc_entry.h >> b/tools/include/linux/orc_entry.h >> new file mode 100644 >> index 000000000000..3d49e3b9dabe >> --- /dev/null >> +++ b/tools/include/linux/orc_entry.h >> @@ -0,0 +1,39 @@ >> +/* SPDX-License-Identifier: GPL-2.0-or-later */ >> +/* >> + * Copyright (C) 2017 Josh Poimboeuf <jpoimboe@redhat.com> >> + */ >> + >> +#ifndef _ORC_ENTRY_H >> +#define _ORC_ENTRY_H >> + >> +#ifndef __ASSEMBLY__ >> +#include <asm/byteorder.h> >> + >> +/* >> + * This struct is more or less a vastly simplified version of the >> DWARF Call >> + * Frame Information standard. It contains only the necessary parts >> of DWARF >> + * CFI, simplified for ease of access by the in-kernel unwinder. It >> tells the >> + * unwinder how to find the previous SP and BP (and sometimes entry >> regs) on >> + * the stack for a given code address. Each instance of the struct >> corresponds >> + * to one or more code locations. >> + */ >> +struct orc_entry { >> + s16 sp_offset; >> + s16 fp_offset; >> +#if defined(__LITTLE_ENDIAN_BITFIELD) >> + unsigned sp_reg:4; >> + unsigned fp_reg:4; >> + unsigned type:3; >> + unsigned end:1; >> +#elif defined(__BIG_ENDIAN_BITFIELD) >> + unsigned fp_reg:4; >> + unsigned sp_reg:4; >> + unsigned unused:4; >> + unsigned end:1; >> + unsigned type:3; >> +# > > nit: > I believe you also need to update fp_reg/bp_offset -> fp_reg/fp_offset > in orc_dump() in orc_dump.c > OK. Will do. Madhavan > - Suraj > >> + >> +#endif /* __ASSEMBLY__ */ >> + >> +#endif /* _ORC_ENTRY_H */ >> diff --git a/tools/objtool/orc_gen.c b/tools/objtool/orc_gen.c >> index dd3c64af9db2..68c317daadbf 100644 >> --- a/tools/objtool/orc_gen.c >> +++ b/tools/objtool/orc_gen.c >> @@ -98,7 +98,7 @@ static int write_orc_entry(struct elf *elf, struct >> section *orc_sec, >> orc = (struct orc_entry *)orc_sec->data->d_buf + idx; >> memcpy(orc, o, sizeof(*orc)); >> orc->sp_offset = bswap_if_needed(orc->sp_offset); >> - orc->bp_offset = bswap_if_needed(orc->bp_offset); >> + orc->fp_offset = bswap_if_needed(orc->fp_offset); >> >> /* populate reloc for ip */ >> if (elf_add_reloc_to_insn(elf, ip_sec, idx * sizeof(int), >> R_X86_64_PC32, >> @@ -149,7 +149,7 @@ int orc_create(struct objtool_file *file) >> >> struct orc_entry null = { >> .sp_reg = ORC_REG_UNDEFINED, >> - .bp_reg = ORC_REG_UNDEFINED, >> + .fp_reg = ORC_REG_UNDEFINED, >> .type = UNWIND_HINT_TYPE_CALL, >> }; >> >> diff --git a/tools/objtool/sync-check.sh b/tools/objtool/sync- >> check.sh >> index ee49b4e9e72c..ef1acb064605 100755 >> --- a/tools/objtool/sync-check.sh >> +++ b/tools/objtool/sync-check.sh >> @@ -18,6 +18,7 @@ arch/x86/include/asm/unwind_hints.h >> arch/x86/lib/x86-opcode-map.txt >> arch/x86/tools/gen-insn-attr-x86.awk >> include/linux/static_call_types.h >> +include/linux/orc_entry.h >> " >> >> SYNC_CHECK_FILES='
diff --git a/arch/x86/include/asm/orc_types.h b/arch/x86/include/asm/orc_types.h index 5a2baf28a1dc..851c9fb9f695 100644 --- a/arch/x86/include/asm/orc_types.h +++ b/arch/x86/include/asm/orc_types.h @@ -8,6 +8,13 @@ #include <linux/types.h> #include <linux/compiler.h> +#include <linux/orc_entry.h> + +/* + * For x86, use the appripriate name for the frame pointer in orc_entry. + */ +#define bp_offset fp_offset +#define bp_reg fp_reg /* * The ORC_REG_* registers are base registers which are used to find other @@ -39,34 +46,4 @@ #define ORC_REG_SP_INDIRECT 9 #define ORC_REG_MAX 15 -#ifndef __ASSEMBLY__ -#include <asm/byteorder.h> - -/* - * This struct is more or less a vastly simplified version of the DWARF Call - * Frame Information standard. It contains only the necessary parts of DWARF - * CFI, simplified for ease of access by the in-kernel unwinder. It tells the - * unwinder how to find the previous SP and BP (and sometimes entry regs) on - * the stack for a given code address. Each instance of the struct corresponds - * to one or more code locations. - */ -struct orc_entry { - s16 sp_offset; - s16 bp_offset; -#if defined(__LITTLE_ENDIAN_BITFIELD) - unsigned sp_reg:4; - unsigned bp_reg:4; - unsigned type:2; - unsigned end:1; -#elif defined(__BIG_ENDIAN_BITFIELD) - unsigned bp_reg:4; - unsigned sp_reg:4; - unsigned unused:5; - unsigned end:1; - unsigned type:2; -#endif -} __packed; - -#endif /* __ASSEMBLY__ */ - #endif /* _ORC_TYPES_H */ diff --git a/include/linux/orc_entry.h b/include/linux/orc_entry.h new file mode 100644 index 000000000000..3d49e3b9dabe --- /dev/null +++ b/include/linux/orc_entry.h @@ -0,0 +1,39 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +/* + * Copyright (C) 2017 Josh Poimboeuf <jpoimboe@redhat.com> + */ + +#ifndef _ORC_ENTRY_H +#define _ORC_ENTRY_H + +#ifndef __ASSEMBLY__ +#include <asm/byteorder.h> + +/* + * This struct is more or less a vastly simplified version of the DWARF Call + * Frame Information standard. It contains only the necessary parts of DWARF + * CFI, simplified for ease of access by the in-kernel unwinder. It tells the + * unwinder how to find the previous SP and BP (and sometimes entry regs) on + * the stack for a given code address. Each instance of the struct corresponds + * to one or more code locations. + */ +struct orc_entry { + s16 sp_offset; + s16 fp_offset; +#if defined(__LITTLE_ENDIAN_BITFIELD) + unsigned sp_reg:4; + unsigned fp_reg:4; + unsigned type:3; + unsigned end:1; +#elif defined(__BIG_ENDIAN_BITFIELD) + unsigned fp_reg:4; + unsigned sp_reg:4; + unsigned unused:4; + unsigned end:1; + unsigned type:3; +#endif +} __packed; + +#endif /* __ASSEMBLY__ */ + +#endif /* _ORC_ENTRY_H */ diff --git a/tools/arch/x86/include/asm/orc_types.h b/tools/arch/x86/include/asm/orc_types.h index 5a2baf28a1dc..851c9fb9f695 100644 --- a/tools/arch/x86/include/asm/orc_types.h +++ b/tools/arch/x86/include/asm/orc_types.h @@ -8,6 +8,13 @@ #include <linux/types.h> #include <linux/compiler.h> +#include <linux/orc_entry.h> + +/* + * For x86, use the appripriate name for the frame pointer in orc_entry. + */ +#define bp_offset fp_offset +#define bp_reg fp_reg /* * The ORC_REG_* registers are base registers which are used to find other @@ -39,34 +46,4 @@ #define ORC_REG_SP_INDIRECT 9 #define ORC_REG_MAX 15 -#ifndef __ASSEMBLY__ -#include <asm/byteorder.h> - -/* - * This struct is more or less a vastly simplified version of the DWARF Call - * Frame Information standard. It contains only the necessary parts of DWARF - * CFI, simplified for ease of access by the in-kernel unwinder. It tells the - * unwinder how to find the previous SP and BP (and sometimes entry regs) on - * the stack for a given code address. Each instance of the struct corresponds - * to one or more code locations. - */ -struct orc_entry { - s16 sp_offset; - s16 bp_offset; -#if defined(__LITTLE_ENDIAN_BITFIELD) - unsigned sp_reg:4; - unsigned bp_reg:4; - unsigned type:2; - unsigned end:1; -#elif defined(__BIG_ENDIAN_BITFIELD) - unsigned bp_reg:4; - unsigned sp_reg:4; - unsigned unused:5; - unsigned end:1; - unsigned type:2; -#endif -} __packed; - -#endif /* __ASSEMBLY__ */ - #endif /* _ORC_TYPES_H */ diff --git a/tools/include/linux/orc_entry.h b/tools/include/linux/orc_entry.h new file mode 100644 index 000000000000..3d49e3b9dabe --- /dev/null +++ b/tools/include/linux/orc_entry.h @@ -0,0 +1,39 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +/* + * Copyright (C) 2017 Josh Poimboeuf <jpoimboe@redhat.com> + */ + +#ifndef _ORC_ENTRY_H +#define _ORC_ENTRY_H + +#ifndef __ASSEMBLY__ +#include <asm/byteorder.h> + +/* + * This struct is more or less a vastly simplified version of the DWARF Call + * Frame Information standard. It contains only the necessary parts of DWARF + * CFI, simplified for ease of access by the in-kernel unwinder. It tells the + * unwinder how to find the previous SP and BP (and sometimes entry regs) on + * the stack for a given code address. Each instance of the struct corresponds + * to one or more code locations. + */ +struct orc_entry { + s16 sp_offset; + s16 fp_offset; +#if defined(__LITTLE_ENDIAN_BITFIELD) + unsigned sp_reg:4; + unsigned fp_reg:4; + unsigned type:3; + unsigned end:1; +#elif defined(__BIG_ENDIAN_BITFIELD) + unsigned fp_reg:4; + unsigned sp_reg:4; + unsigned unused:4; + unsigned end:1; + unsigned type:3; +#endif +} __packed; + +#endif /* __ASSEMBLY__ */ + +#endif /* _ORC_ENTRY_H */ diff --git a/tools/objtool/orc_gen.c b/tools/objtool/orc_gen.c index dd3c64af9db2..68c317daadbf 100644 --- a/tools/objtool/orc_gen.c +++ b/tools/objtool/orc_gen.c @@ -98,7 +98,7 @@ static int write_orc_entry(struct elf *elf, struct section *orc_sec, orc = (struct orc_entry *)orc_sec->data->d_buf + idx; memcpy(orc, o, sizeof(*orc)); orc->sp_offset = bswap_if_needed(orc->sp_offset); - orc->bp_offset = bswap_if_needed(orc->bp_offset); + orc->fp_offset = bswap_if_needed(orc->fp_offset); /* populate reloc for ip */ if (elf_add_reloc_to_insn(elf, ip_sec, idx * sizeof(int), R_X86_64_PC32, @@ -149,7 +149,7 @@ int orc_create(struct objtool_file *file) struct orc_entry null = { .sp_reg = ORC_REG_UNDEFINED, - .bp_reg = ORC_REG_UNDEFINED, + .fp_reg = ORC_REG_UNDEFINED, .type = UNWIND_HINT_TYPE_CALL, }; diff --git a/tools/objtool/sync-check.sh b/tools/objtool/sync-check.sh index ee49b4e9e72c..ef1acb064605 100755 --- a/tools/objtool/sync-check.sh +++ b/tools/objtool/sync-check.sh @@ -18,6 +18,7 @@ arch/x86/include/asm/unwind_hints.h arch/x86/lib/x86-opcode-map.txt arch/x86/tools/gen-insn-attr-x86.awk include/linux/static_call_types.h +include/linux/orc_entry.h " SYNC_CHECK_FILES='