From 534af1082329392bc29f6badf815e69ae2ae0f4c Mon Sep 17 00:00:00 2001 From: Jason Wessel Date: Thu, 5 Aug 2010 09:22:20 -0500 Subject: kgdb,kdb: individual register set and and get API The kdb shell specification includes the ability to get and set architecture specific registers by name. For the time being individual register get and set will be implemented on a per architecture basis. If an architecture defines DBG_MAX_REG_NUM > 0 then kdb and the gdbstub will use the capability for individually getting and setting architecture specific registers. Signed-off-by: Jason Wessel --- include/linux/kgdb.h | 13 +++++++++++++ 1 file changed, 13 insertions(+) (limited to 'include') diff --git a/include/linux/kgdb.h b/include/linux/kgdb.h index 9340f34d1bb5..d5eb882e01f3 100644 --- a/include/linux/kgdb.h +++ b/include/linux/kgdb.h @@ -90,6 +90,19 @@ struct kgdb_bkpt { enum kgdb_bpstate state; }; +struct dbg_reg_def_t { + char *name; + int size; + int offset; +}; + +#ifndef DBG_MAX_REG_NUM +#define DBG_MAX_REG_NUM 0 +#else +extern struct dbg_reg_def_t dbg_reg_def[]; +extern char *dbg_get_reg(int regno, void *mem, struct pt_regs *regs); +extern int dbg_set_reg(int regno, void *mem, struct pt_regs *regs); +#endif #ifndef KGDB_MAX_BREAKPOINTS # define KGDB_MAX_BREAKPOINTS 1000 #endif -- cgit v1.2.3 From 55751145dc1e08e16df418cdd101661f5c6ac991 Mon Sep 17 00:00:00 2001 From: Jason Wessel Date: Thu, 5 Aug 2010 09:22:21 -0500 Subject: gdbstub: Implement gdbserial 'p' and 'P' packets The gdbserial 'p' and 'P' packets allow gdb to individually get and set registers instead of querying for all the available registers. Signed-off-by: Jason Wessel --- include/linux/kgdb.h | 2 +- kernel/debug/gdbstub.c | 97 +++++++++++++++++++++++++++++++++++++++----------- 2 files changed, 78 insertions(+), 21 deletions(-) (limited to 'include') diff --git a/include/linux/kgdb.h b/include/linux/kgdb.h index d5eb882e01f3..cc96f0f23e04 100644 --- a/include/linux/kgdb.h +++ b/include/linux/kgdb.h @@ -294,7 +294,7 @@ extern void kgdb_unregister_io_module(struct kgdb_io *local_kgdb_io_ops); extern struct kgdb_io *dbg_io_ops; extern int kgdb_hex2long(char **ptr, unsigned long *long_val); -extern int kgdb_mem2hex(char *mem, char *buf, int count); +extern char *kgdb_mem2hex(char *mem, char *buf, int count); extern int kgdb_hex2mem(char *buf, char *mem, int count); extern int kgdb_isremovedbreak(unsigned long addr); diff --git a/kernel/debug/gdbstub.c b/kernel/debug/gdbstub.c index 006bad8905d3..4ef9dddf4588 100644 --- a/kernel/debug/gdbstub.c +++ b/kernel/debug/gdbstub.c @@ -225,7 +225,7 @@ void gdbstub_msg_write(const char *s, int len) * buf. Return a pointer to the last char put in buf (null). May * return an error. */ -int kgdb_mem2hex(char *mem, char *buf, int count) +char *kgdb_mem2hex(char *mem, char *buf, int count) { char *tmp; int err; @@ -237,17 +237,16 @@ int kgdb_mem2hex(char *mem, char *buf, int count) tmp = buf + count; err = probe_kernel_read(tmp, mem, count); - if (!err) { - while (count > 0) { - buf = pack_hex_byte(buf, *tmp); - tmp++; - count--; - } - - *buf = 0; + if (err) + return NULL; + while (count > 0) { + buf = pack_hex_byte(buf, *tmp); + tmp++; + count--; } + *buf = 0; - return err; + return buf; } /* @@ -481,8 +480,7 @@ static void gdb_cmd_status(struct kgdb_state *ks) pack_hex_byte(&remcom_out_buffer[1], ks->signo); } -/* Handle the 'g' get registers request */ -static void gdb_cmd_getregs(struct kgdb_state *ks) +static void gdb_get_regs_helper(struct kgdb_state *ks) { struct task_struct *thread; void *local_debuggerinfo; @@ -523,6 +521,12 @@ static void gdb_cmd_getregs(struct kgdb_state *ks) */ sleeping_thread_to_gdb_regs(gdb_regs, thread); } +} + +/* Handle the 'g' get registers request */ +static void gdb_cmd_getregs(struct kgdb_state *ks) +{ + gdb_get_regs_helper(ks); kgdb_mem2hex((char *)gdb_regs, remcom_out_buffer, NUMREGBYTES); } @@ -545,13 +549,13 @@ static void gdb_cmd_memread(struct kgdb_state *ks) char *ptr = &remcom_in_buffer[1]; unsigned long length; unsigned long addr; - int err; + char *err; if (kgdb_hex2long(&ptr, &addr) > 0 && *ptr++ == ',' && kgdb_hex2long(&ptr, &length) > 0) { err = kgdb_mem2hex((char *)addr, remcom_out_buffer, length); - if (err) - error_packet(remcom_out_buffer, err); + if (!err) + error_packet(remcom_out_buffer, -EINVAL); } else { error_packet(remcom_out_buffer, -EINVAL); } @@ -568,6 +572,52 @@ static void gdb_cmd_memwrite(struct kgdb_state *ks) strcpy(remcom_out_buffer, "OK"); } +#if DBG_MAX_REG_NUM > 0 +static char *gdb_hex_reg_helper(int regnum, char *out) +{ + int i; + int offset = 0; + + for (i = 0; i < regnum; i++) + offset += dbg_reg_def[i].size; + return kgdb_mem2hex((char *)gdb_regs + offset, out, + dbg_reg_def[i].size); +} + +/* Handle the 'p' individual regster get */ +static void gdb_cmd_reg_get(struct kgdb_state *ks) +{ + unsigned long regnum; + char *ptr = &remcom_in_buffer[1]; + + kgdb_hex2long(&ptr, ®num); + if (regnum >= DBG_MAX_REG_NUM) { + error_packet(remcom_out_buffer, -EINVAL); + return; + } + gdb_get_regs_helper(ks); + gdb_hex_reg_helper(regnum, remcom_out_buffer); +} + +/* Handle the 'P' individual regster set */ +static void gdb_cmd_reg_set(struct kgdb_state *ks) +{ + unsigned long regnum; + char *ptr = &remcom_in_buffer[1]; + + kgdb_hex2long(&ptr, ®num); + if (*ptr++ != '=' || + !(!kgdb_usethread || kgdb_usethread == current) || + !dbg_get_reg(regnum, gdb_regs, ks->linux_regs)) { + error_packet(remcom_out_buffer, -EINVAL); + return; + } + kgdb_hex2mem(ptr, (char *)gdb_regs, dbg_reg_def[regnum].size); + dbg_set_reg(regnum, gdb_regs, ks->linux_regs); + strcpy(remcom_out_buffer, "OK"); +} +#endif /* DBG_MAX_REG_NUM > 0 */ + /* Handle the 'X' memory binary write bytes */ static void gdb_cmd_binwrite(struct kgdb_state *ks) { @@ -874,8 +924,11 @@ int gdb_serial_stub(struct kgdb_state *ks) int error = 0; int tmp; - /* Clear the out buffer. */ + /* Initialize comm buffer and globals. */ memset(remcom_out_buffer, 0, sizeof(remcom_out_buffer)); + kgdb_usethread = kgdb_info[ks->cpu].task; + ks->kgdb_usethreadid = shadow_pid(kgdb_info[ks->cpu].task->pid); + ks->pass_exception = 0; if (kgdb_connected) { unsigned char thref[BUF_THREAD_ID_SIZE]; @@ -892,10 +945,6 @@ int gdb_serial_stub(struct kgdb_state *ks) put_packet(remcom_out_buffer); } - kgdb_usethread = kgdb_info[ks->cpu].task; - ks->kgdb_usethreadid = shadow_pid(kgdb_info[ks->cpu].task->pid); - ks->pass_exception = 0; - while (1) { error = 0; @@ -920,6 +969,14 @@ int gdb_serial_stub(struct kgdb_state *ks) case 'M': /* MAA..AA,LLLL: Write LLLL bytes at address AA..AA */ gdb_cmd_memwrite(ks); break; +#if DBG_MAX_REG_NUM > 0 + case 'p': /* pXX Return gdb register XX (in hex) */ + gdb_cmd_reg_get(ks); + break; + case 'P': /* PXX=aaaa Set gdb register XX to aaaa (in hex) */ + gdb_cmd_reg_set(ks); + break; +#endif /* DBG_MAX_REG_NUM > 0 */ case 'X': /* XAA..AA,LLLL: Write LLLL bytes at address AA..AA */ gdb_cmd_binwrite(ks); break; -- cgit v1.2.3