[PATCH RFC v2 4/8] signal: Introduce TRAP_PERF si_code and si_perf to siginfo
From: Marco Elver <elver@google.com>
Date: 2021-03-10 10:42:58
Also in:
linux-fsdevel, linux-kselftest, lkml
Subsystem:
filesystems (vfs and infrastructure), generic include/asm header files, m68k architecture, the rest, x86 architecture (32-bit and 64-bit) · Maintainers:
Alexander Viro, Christian Brauner, Arnd Bergmann, Geert Uytterhoeven, Linus Torvalds, Thomas Gleixner, Ingo Molnar, Borislav Petkov, Dave Hansen
Introduces the TRAP_PERF si_code, and associated siginfo_t field si_perf. These will be used by the perf event subsystem to send signals (if requested) to the task where an event occurred. Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> # m68k Acked-by: Arnd Bergmann <arnd@arndb.de> # asm-generic Signed-off-by: Marco Elver <elver@google.com> --- arch/m68k/kernel/signal.c | 3 +++ arch/x86/kernel/signal_compat.c | 5 ++++- fs/signalfd.c | 4 ++++ include/linux/compat.h | 2 ++ include/linux/signal.h | 1 + include/uapi/asm-generic/siginfo.h | 6 +++++- include/uapi/linux/signalfd.h | 4 +++- kernel/signal.c | 11 +++++++++++ 8 files changed, 33 insertions(+), 3 deletions(-)
diff --git a/arch/m68k/kernel/signal.c b/arch/m68k/kernel/signal.c
index 349570f16a78..a4b7ee1df211 100644
--- a/arch/m68k/kernel/signal.c
+++ b/arch/m68k/kernel/signal.c@@ -622,6 +622,9 @@ static inline void siginfo_build_tests(void) /* _sigfault._addr_pkey */ BUILD_BUG_ON(offsetof(siginfo_t, si_pkey) != 0x12); + /* _sigfault._perf */ + BUILD_BUG_ON(offsetof(siginfo_t, si_perf) != 0x10); + /* _sigpoll */ BUILD_BUG_ON(offsetof(siginfo_t, si_band) != 0x0c); BUILD_BUG_ON(offsetof(siginfo_t, si_fd) != 0x10);
diff --git a/arch/x86/kernel/signal_compat.c b/arch/x86/kernel/signal_compat.c
index a5330ff498f0..0e5d0a7e203b 100644
--- a/arch/x86/kernel/signal_compat.c
+++ b/arch/x86/kernel/signal_compat.c@@ -29,7 +29,7 @@ static inline void signal_compat_build_tests(void) BUILD_BUG_ON(NSIGFPE != 15); BUILD_BUG_ON(NSIGSEGV != 9); BUILD_BUG_ON(NSIGBUS != 5); - BUILD_BUG_ON(NSIGTRAP != 5); + BUILD_BUG_ON(NSIGTRAP != 6); BUILD_BUG_ON(NSIGCHLD != 6); BUILD_BUG_ON(NSIGSYS != 2);
@@ -138,6 +138,9 @@ static inline void signal_compat_build_tests(void) BUILD_BUG_ON(offsetof(siginfo_t, si_pkey) != 0x20); BUILD_BUG_ON(offsetof(compat_siginfo_t, si_pkey) != 0x14); + BUILD_BUG_ON(offsetof(siginfo_t, si_perf) != 0x18); + BUILD_BUG_ON(offsetof(compat_siginfo_t, si_perf) != 0x10); + CHECK_CSI_OFFSET(_sigpoll); CHECK_CSI_SIZE (_sigpoll, 2*sizeof(int)); CHECK_SI_SIZE (_sigpoll, 4*sizeof(int));
diff --git a/fs/signalfd.c b/fs/signalfd.c
index 456046e15873..040a1142915f 100644
--- a/fs/signalfd.c
+++ b/fs/signalfd.c@@ -134,6 +134,10 @@ static int signalfd_copyinfo(struct signalfd_siginfo __user *uinfo, #endif new.ssi_addr_lsb = (short) kinfo->si_addr_lsb; break; + case SIL_PERF_EVENT: + new.ssi_addr = (long) kinfo->si_addr; + new.ssi_perf = kinfo->si_perf; + break; case SIL_CHLD: new.ssi_pid = kinfo->si_pid; new.ssi_uid = kinfo->si_uid;
diff --git a/include/linux/compat.h b/include/linux/compat.h
index 6e65be753603..c8821d966812 100644
--- a/include/linux/compat.h
+++ b/include/linux/compat.h@@ -236,6 +236,8 @@ typedef struct compat_siginfo { char _dummy_pkey[__COMPAT_ADDR_BND_PKEY_PAD]; u32 _pkey; } _addr_pkey; + /* used when si_code=TRAP_PERF */ + compat_u64 _perf; }; } _sigfault;
diff --git a/include/linux/signal.h b/include/linux/signal.h
index 205526c4003a..1e98548d7cf6 100644
--- a/include/linux/signal.h
+++ b/include/linux/signal.h@@ -43,6 +43,7 @@ enum siginfo_layout { SIL_FAULT_MCEERR, SIL_FAULT_BNDERR, SIL_FAULT_PKUERR, + SIL_PERF_EVENT, SIL_CHLD, SIL_RT, SIL_SYS,
diff --git a/include/uapi/asm-generic/siginfo.h b/include/uapi/asm-generic/siginfo.h
index d2597000407a..d0bb9125c853 100644
--- a/include/uapi/asm-generic/siginfo.h
+++ b/include/uapi/asm-generic/siginfo.h@@ -91,6 +91,8 @@ union __sifields { char _dummy_pkey[__ADDR_BND_PKEY_PAD]; __u32 _pkey; } _addr_pkey; + /* used when si_code=TRAP_PERF */ + __u64 _perf; }; } _sigfault;
@@ -155,6 +157,7 @@ typedef struct siginfo { #define si_lower _sifields._sigfault._addr_bnd._lower #define si_upper _sifields._sigfault._addr_bnd._upper #define si_pkey _sifields._sigfault._addr_pkey._pkey +#define si_perf _sifields._sigfault._perf #define si_band _sifields._sigpoll._band #define si_fd _sifields._sigpoll._fd #define si_call_addr _sifields._sigsys._call_addr
@@ -253,7 +256,8 @@ typedef struct siginfo { #define TRAP_BRANCH 3 /* process taken branch trap */ #define TRAP_HWBKPT 4 /* hardware breakpoint/watchpoint */ #define TRAP_UNK 5 /* undiagnosed trap */ -#define NSIGTRAP 5 +#define TRAP_PERF 6 /* perf event with sigtrap=1 */ +#define NSIGTRAP 6 /* * There is an additional set of SIGTRAP si_codes used by ptrace
diff --git a/include/uapi/linux/signalfd.h b/include/uapi/linux/signalfd.h
index 83429a05b698..7e333042c7e3 100644
--- a/include/uapi/linux/signalfd.h
+++ b/include/uapi/linux/signalfd.h@@ -39,6 +39,8 @@ struct signalfd_siginfo { __s32 ssi_syscall; __u64 ssi_call_addr; __u32 ssi_arch; + __u32 __pad3; + __u64 ssi_perf; /* * Pad strcture to 128 bytes. Remember to update the
@@ -49,7 +51,7 @@ struct signalfd_siginfo { * comes out of a read(2) and we really don't want to have * a compat on read(2). */ - __u8 __pad[28]; + __u8 __pad[16]; };
diff --git a/kernel/signal.c b/kernel/signal.c
index ba4d1ef39a9e..f68351825e5e 100644
--- a/kernel/signal.c
+++ b/kernel/signal.c@@ -1199,6 +1199,7 @@ static inline bool has_si_pid_and_uid(struct kernel_siginfo *info) case SIL_FAULT_MCEERR: case SIL_FAULT_BNDERR: case SIL_FAULT_PKUERR: + case SIL_PERF_EVENT: case SIL_SYS: ret = false; break;
@@ -2531,6 +2532,7 @@ static void hide_si_addr_tag_bits(struct ksignal *ksig) case SIL_FAULT_MCEERR: case SIL_FAULT_BNDERR: case SIL_FAULT_PKUERR: + case SIL_PERF_EVENT: ksig->info.si_addr = arch_untagged_si_addr( ksig->info.si_addr, ksig->sig, ksig->info.si_code); break;
@@ -3333,6 +3335,10 @@ void copy_siginfo_to_external32(struct compat_siginfo *to, #endif to->si_pkey = from->si_pkey; break; + case SIL_PERF_EVENT: + to->si_addr = ptr_to_compat(from->si_addr); + to->si_perf = from->si_perf; + break; case SIL_CHLD: to->si_pid = from->si_pid; to->si_uid = from->si_uid;
@@ -3413,6 +3419,10 @@ static int post_copy_siginfo_from_user32(kernel_siginfo_t *to, #endif to->si_pkey = from->si_pkey; break; + case SIL_PERF_EVENT: + to->si_addr = compat_ptr(from->si_addr); + to->si_perf = from->si_perf; + break; case SIL_CHLD: to->si_pid = from->si_pid; to->si_uid = from->si_uid;
@@ -4593,6 +4603,7 @@ static inline void siginfo_buildtime_checks(void) CHECK_OFFSET(si_lower); CHECK_OFFSET(si_upper); CHECK_OFFSET(si_pkey); + CHECK_OFFSET(si_perf); /* sigpoll */ CHECK_OFFSET(si_band);
--
2.30.1.766.gb4fecdf3b7-goog