X-Git-Url: http://git.efficios.com/?a=blobdiff_plain;f=gdb%2Famd64-linux-nat.c;h=f98d992070a340d0c37d249f0a8c10a3c5d71aa9;hb=8948cc6971fb82feffc49e2d21747111466ad642;hp=d8e424a303d46a5bb3df035612482fb1a802e1f5;hpb=2acf3cd06577b80adb96df754f910da8b754c7dc;p=deliverable%2Fbinutils-gdb.git diff --git a/gdb/amd64-linux-nat.c b/gdb/amd64-linux-nat.c index d8e424a303..f98d992070 100644 --- a/gdb/amd64-linux-nat.c +++ b/gdb/amd64-linux-nat.c @@ -1,6 +1,6 @@ /* Native-dependent code for GNU/Linux x86-64. - Copyright (C) 2001-2014 Free Software Foundation, Inc. + Copyright (C) 2001-2020 Free Software Foundation, Inc. Contributed by Jiri Smid, SuSE Labs. This file is part of GDB. @@ -20,62 +20,42 @@ #include "defs.h" #include "inferior.h" -#include "gdbcore.h" #include "regcache.h" -#include "regset.h" -#include "linux-nat.h" -#include "amd64-linux-tdep.h" -#include "nat/linux-btrace.h" -#include "btrace.h" - -#include "gdb_assert.h" -#include #include "elf/common.h" #include -#include -#include -#include -#include -#include +#include "nat/gdb_ptrace.h" #include -/* FIXME ezannoni-2003-07-09: we need to be included after - because the latter redefines FS and GS for no apparent - reason, and those definitions don't match the ones that libpthread_db - uses, which come from . */ -/* ezannoni-2003-07-09: I think this is fixed. The extraneous defs have - been removed from ptrace.h in the kernel. However, better safe than - sorry. */ -#include #include -#include "gdb_proc_service.h" - -/* Prototypes for supply_gregset etc. */ #include "gregset.h" +#include "gdb_proc_service.h" +#include "amd64-nat.h" #include "amd64-tdep.h" +#include "amd64-linux-tdep.h" #include "i386-linux-tdep.h" -#include "amd64-nat.h" -#include "i386-nat.h" -#include "i386-xstate.h" +#include "gdbsupport/x86-xstate.h" -#ifndef PTRACE_GETREGSET -#define PTRACE_GETREGSET 0x4204 -#endif +#include "x86-linux-nat.h" +#include "nat/linux-ptrace.h" +#include "nat/amd64-linux-siginfo.h" -#ifndef PTRACE_SETREGSET -#define PTRACE_SETREGSET 0x4205 +/* This definition comes from prctl.h. Kernels older than 2.5.64 + do not have it. */ +#ifndef PTRACE_ARCH_PRCTL +#define PTRACE_ARCH_PRCTL 30 #endif -/* Per-thread arch-specific data we want to keep. */ - -struct arch_lwp_info +struct amd64_linux_nat_target final : public x86_linux_nat_target { - /* Non-zero if our copy differs from what's recorded in the thread. */ - int debug_registers_changed; + /* Add our register access methods. */ + void fetch_registers (struct regcache *, int) override; + void store_registers (struct regcache *, int) override; + + bool low_siginfo_fixup (siginfo_t *ptrace, gdb_byte *inf, int direction) + override; }; -/* Does the current host support PTRACE_GETREGSET? */ -static int have_ptrace_getregset = -1; +static amd64_linux_nat_target the_amd64_linux_nat_target; /* Mapping between the general-purpose registers in GNU/Linux x86-64 `struct user' format and GDB's register cache layout for GNU/Linux @@ -104,6 +84,7 @@ static int amd64_linux_gregset32_reg_offset[] = -1, -1, /* MPX registers BNDCFGU, BNDSTATUS. */ -1, -1, -1, -1, -1, -1, -1, -1, /* k0 ... k7 (AVX512) */ -1, -1, -1, -1, -1, -1, -1, -1, /* zmm0 ... zmm7 (AVX512) */ + -1, /* PKEYS register PKRU */ ORIG_RAX * 8 /* "orig_eax" */ }; @@ -111,6 +92,71 @@ static int amd64_linux_gregset32_reg_offset[] = /* Transfering the general-purpose registers between GDB, inferiors and core files. */ +/* See amd64_collect_native_gregset. This linux specific version handles + issues with negative EAX values not being restored correctly upon syscall + return when debugging 32-bit targets. It has no effect on 64-bit + targets. */ + +static void +amd64_linux_collect_native_gregset (const struct regcache *regcache, + void *gregs, int regnum) +{ + amd64_collect_native_gregset (regcache, gregs, regnum); + + struct gdbarch *gdbarch = regcache->arch (); + if (gdbarch_bfd_arch_info (gdbarch)->bits_per_word == 32) + { + /* Sign extend EAX value to avoid potential syscall restart + problems. + + On Linux, when a syscall is interrupted by a signal, the + (kernel function implementing the) syscall may return + -ERESTARTSYS when a signal occurs. Doing so indicates that + the syscall is restartable. Then, depending on settings + associated with the signal handler, and after the signal + handler is called, the kernel can then either return -EINTR + or it can cause the syscall to be restarted. We are + concerned with the latter case here. + + On (32-bit) i386, the status (-ERESTARTSYS) is placed in the + EAX register. When debugging a 32-bit process from a 64-bit + (amd64) GDB, the debugger fetches 64-bit registers even + though the process being debugged is only 32-bit. The + register cache is only 32 bits wide though; GDB discards the + high 32 bits when placing 64-bit values in the 32-bit + regcache. Normally, this is not a problem since the 32-bit + process should only care about the lower 32-bit portions of + these registers. That said, it can happen that the 64-bit + value being restored will be different from the 64-bit value + that was originally retrieved from the kernel. The one place + (that we know of) where it does matter is in the kernel's + syscall restart code. The kernel's code for restarting a + syscall after a signal expects to see a negative value + (specifically -ERESTARTSYS) in the 64-bit RAX register in + order to correctly cause a syscall to be restarted. + + The call to amd64_collect_native_gregset, above, is setting + the high 32 bits of RAX (and other registers too) to 0. For + syscall restart, we need to sign extend EAX so that RAX will + appear as a negative value when EAX is set to -ERESTARTSYS. + This in turn will cause the signal handling code in the + kernel to recognize -ERESTARTSYS which will in turn cause the + syscall to be restarted. + + The test case gdb.base/interrupt.exp tests for this problem. + Without this sign extension code in place, it'll show + a number of failures when testing against unix/-m32. */ + + if (regnum == -1 || regnum == I386_EAX_REGNUM) + { + void *ptr = ((gdb_byte *) gregs + + amd64_linux_gregset32_reg_offset[I386_EAX_REGNUM]); + + *(int64_t *) ptr = *(int32_t *) ptr; + } + } +} + /* Fill GDB's register cache with the general-purpose register values in *GREGSETP. */ @@ -128,7 +174,7 @@ void fill_gregset (const struct regcache *regcache, elf_gregset_t *gregsetp, int regnum) { - amd64_collect_native_gregset (regcache, gregsetp, regnum); + amd64_linux_collect_native_gregset (regcache, gregsetp, regnum); } /* Transfering floating-point registers between GDB, inferiors and cores. */ @@ -160,17 +206,16 @@ fill_fpregset (const struct regcache *regcache, this for all registers (including the floating point and SSE registers). */ -static void -amd64_linux_fetch_inferior_registers (struct target_ops *ops, - struct regcache *regcache, int regnum) +void +amd64_linux_nat_target::fetch_registers (struct regcache *regcache, int regnum) { - struct gdbarch *gdbarch = get_regcache_arch (regcache); + struct gdbarch *gdbarch = regcache->arch (); int tid; /* GNU/Linux LWP ID's are process ID's. */ - tid = ptid_get_lwp (inferior_ptid); + tid = regcache->ptid ().lwp (); if (tid == 0) - tid = ptid_get_pid (inferior_ptid); /* Not a threaded program. */ + tid = regcache->ptid ().pid (); /* Not a threaded program. */ if (regnum == -1 || amd64_native_gregset_supplies_p (gdbarch, regnum)) { @@ -188,11 +233,17 @@ amd64_linux_fetch_inferior_registers (struct target_ops *ops, { elf_fpregset_t fpregs; - if (have_ptrace_getregset) + if (have_ptrace_getregset == TRIBOOL_TRUE) { - char xstateregs[I386_XSTATE_MAX_SIZE]; + char xstateregs[X86_XSTATE_MAX_SIZE]; struct iovec iov; + /* Pre-4.14 kernels have a bug (fixed by commit 0852b374173b + "x86/fpu: Add FPU state copying quirk to handle XRSTOR failure on + Intel Skylake CPUs") that sometimes causes the mxcsr location in + xstateregs not to be copied by PTRACE_GETREGSET. Make sure that + the location is at least initialized with a defined value. */ + memset (xstateregs, 0, sizeof (xstateregs)); iov.iov_base = xstateregs; iov.iov_len = sizeof (xstateregs); if (ptrace (PTRACE_GETREGSET, tid, @@ -208,6 +259,30 @@ amd64_linux_fetch_inferior_registers (struct target_ops *ops, amd64_supply_fxsave (regcache, -1, &fpregs); } +#ifndef HAVE_STRUCT_USER_REGS_STRUCT_FS_BASE + { + /* PTRACE_ARCH_PRCTL is obsolete since 2.6.25, where the + fs_base and gs_base fields of user_regs_struct can be + used directly. */ + unsigned long base; + + if (regnum == -1 || regnum == AMD64_FSBASE_REGNUM) + { + if (ptrace (PTRACE_ARCH_PRCTL, tid, &base, ARCH_GET_FS) < 0) + perror_with_name (_("Couldn't get segment register fs_base")); + + regcache->raw_supply (AMD64_FSBASE_REGNUM, &base); + } + + if (regnum == -1 || regnum == AMD64_GSBASE_REGNUM) + { + if (ptrace (PTRACE_ARCH_PRCTL, tid, &base, ARCH_GET_GS) < 0) + perror_with_name (_("Couldn't get segment register gs_base")); + + regcache->raw_supply (AMD64_GSBASE_REGNUM, &base); + } + } +#endif } } @@ -215,17 +290,16 @@ amd64_linux_fetch_inferior_registers (struct target_ops *ops, -1, do this for all registers (including the floating-point and SSE registers). */ -static void -amd64_linux_store_inferior_registers (struct target_ops *ops, - struct regcache *regcache, int regnum) +void +amd64_linux_nat_target::store_registers (struct regcache *regcache, int regnum) { - struct gdbarch *gdbarch = get_regcache_arch (regcache); + struct gdbarch *gdbarch = regcache->arch (); int tid; /* GNU/Linux LWP ID's are process ID's. */ - tid = ptid_get_lwp (inferior_ptid); + tid = regcache->ptid ().lwp (); if (tid == 0) - tid = ptid_get_pid (inferior_ptid); /* Not a threaded program. */ + tid = regcache->ptid ().pid (); /* Not a threaded program. */ if (regnum == -1 || amd64_native_gregset_supplies_p (gdbarch, regnum)) { @@ -234,7 +308,7 @@ amd64_linux_store_inferior_registers (struct target_ops *ops, if (ptrace (PTRACE_GETREGS, tid, 0, (long) ®s) < 0) perror_with_name (_("Couldn't get registers")); - amd64_collect_native_gregset (regcache, ®s, regnum); + amd64_linux_collect_native_gregset (regcache, ®s, regnum); if (ptrace (PTRACE_SETREGS, tid, 0, (long) ®s) < 0) perror_with_name (_("Couldn't write registers")); @@ -247,9 +321,9 @@ amd64_linux_store_inferior_registers (struct target_ops *ops, { elf_fpregset_t fpregs; - if (have_ptrace_getregset) + if (have_ptrace_getregset == TRIBOOL_TRUE) { - char xstateregs[I386_XSTATE_MAX_SIZE]; + char xstateregs[X86_XSTATE_MAX_SIZE]; struct iovec iov; iov.iov_base = xstateregs; @@ -274,259 +348,59 @@ amd64_linux_store_inferior_registers (struct target_ops *ops, if (ptrace (PTRACE_SETFPREGS, tid, 0, (long) &fpregs) < 0) perror_with_name (_("Couldn't write floating point status")); } - } -} - -/* Support for debug registers. */ -static unsigned long -x86_linux_dr_get (ptid_t ptid, int regnum) -{ - int tid; - unsigned long value; +#ifndef HAVE_STRUCT_USER_REGS_STRUCT_FS_BASE + { + /* PTRACE_ARCH_PRCTL is obsolete since 2.6.25, where the + fs_base and gs_base fields of user_regs_struct can be + used directly. */ + void *base; - tid = ptid_get_lwp (ptid); - if (tid == 0) - tid = ptid_get_pid (ptid); - - errno = 0; - value = ptrace (PTRACE_PEEKUSER, tid, - offsetof (struct user, u_debugreg[regnum]), 0); - if (errno != 0) - perror_with_name (_("Couldn't read debug register")); - - return value; -} - -/* Set debug register REGNUM to VALUE in only the one LWP of PTID. */ - -static void -x86_linux_dr_set (ptid_t ptid, int regnum, unsigned long value) -{ - int tid; - - tid = ptid_get_lwp (ptid); - if (tid == 0) - tid = ptid_get_pid (ptid); - - errno = 0; - ptrace (PTRACE_POKEUSER, tid, - offsetof (struct user, u_debugreg[regnum]), value); - if (errno != 0) - perror_with_name (_("Couldn't write debug register")); -} - -/* Return the inferior's debug register REGNUM. */ - -static CORE_ADDR -x86_linux_dr_get_addr (int regnum) -{ - /* DR6 and DR7 are retrieved with some other way. */ - gdb_assert (DR_FIRSTADDR <= regnum && regnum <= DR_LASTADDR); - - return x86_linux_dr_get (inferior_ptid, regnum); -} - -/* Return the inferior's DR7 debug control register. */ - -static unsigned long -x86_linux_dr_get_control (void) -{ - return x86_linux_dr_get (inferior_ptid, DR_CONTROL); -} - -/* Get DR_STATUS from only the one LWP of INFERIOR_PTID. */ - -static unsigned long -x86_linux_dr_get_status (void) -{ - return x86_linux_dr_get (inferior_ptid, DR_STATUS); -} - -/* Callback for iterate_over_lwps. Update the debug registers of - LWP. */ - -static int -update_debug_registers_callback (struct lwp_info *lwp, void *arg) -{ - if (lwp->arch_private == NULL) - lwp->arch_private = XCNEW (struct arch_lwp_info); - - /* The actual update is done later just before resuming the lwp, we - just mark that the registers need updating. */ - lwp->arch_private->debug_registers_changed = 1; - - /* If the lwp isn't stopped, force it to momentarily pause, so we - can update its debug registers. */ - if (!lwp->stopped) - linux_stop_lwp (lwp); - - /* Continue the iteration. */ - return 0; -} - -/* Set DR_CONTROL to CONTROL in all LWPs of the current inferior. */ - -static void -x86_linux_dr_set_control (unsigned long control) -{ - ptid_t pid_ptid = pid_to_ptid (ptid_get_pid (inferior_ptid)); - - iterate_over_lwps (pid_ptid, update_debug_registers_callback, NULL); -} - -/* Set address REGNUM (zero based) to ADDR in all LWPs of the current - inferior. */ - -static void -x86_linux_dr_set_addr (int regnum, CORE_ADDR addr) -{ - ptid_t pid_ptid = pid_to_ptid (ptid_get_pid (inferior_ptid)); - - gdb_assert (regnum >= 0 && regnum <= DR_LASTADDR - DR_FIRSTADDR); - - iterate_over_lwps (pid_ptid, update_debug_registers_callback, NULL); -} - -/* Called when resuming a thread. - If the debug regs have changed, update the thread's copies. */ - -static void -x86_linux_prepare_to_resume (struct lwp_info *lwp) -{ - int clear_status = 0; - - /* NULL means this is the main thread still going through the shell, - or, no watchpoint has been set yet. In that case, there's - nothing to do. */ - if (lwp->arch_private == NULL) - return; - - if (lwp->arch_private->debug_registers_changed) - { - struct i386_debug_reg_state *state - = i386_debug_reg_state (ptid_get_pid (lwp->ptid)); - int i; - - /* On Linux kernel before 2.6.33 commit - 72f674d203cd230426437cdcf7dd6f681dad8b0d - if you enable a breakpoint by the DR_CONTROL bits you need to have - already written the corresponding DR_FIRSTADDR...DR_LASTADDR registers. - - Ensure DR_CONTROL gets written as the very last register here. */ - - /* Clear DR_CONTROL first. In some cases, setting DR0-3 to a - value that doesn't match what is enabled in DR_CONTROL - results in EINVAL. */ - x86_linux_dr_set (lwp->ptid, DR_CONTROL, 0); - - for (i = DR_FIRSTADDR; i <= DR_LASTADDR; i++) - if (state->dr_ref_count[i] > 0) + if (regnum == -1 || regnum == AMD64_FSBASE_REGNUM) { - x86_linux_dr_set (lwp->ptid, i, state->dr_mirror[i]); + regcache->raw_collect (AMD64_FSBASE_REGNUM, &base); - /* If we're setting a watchpoint, any change the inferior - had done itself to the debug registers needs to be - discarded, otherwise, i386_stopped_data_address can get - confused. */ - clear_status = 1; + if (ptrace (PTRACE_ARCH_PRCTL, tid, base, ARCH_SET_FS) < 0) + perror_with_name (_("Couldn't write segment register fs_base")); } + if (regnum == -1 || regnum == AMD64_GSBASE_REGNUM) + { - /* If DR_CONTROL is supposed to be zero, we've already set it - above. */ - if (state->dr_control_mirror != 0) - x86_linux_dr_set (lwp->ptid, DR_CONTROL, state->dr_control_mirror); - - lwp->arch_private->debug_registers_changed = 0; + regcache->raw_collect (AMD64_GSBASE_REGNUM, &base); + if (ptrace (PTRACE_ARCH_PRCTL, tid, base, ARCH_SET_GS) < 0) + perror_with_name (_("Couldn't write segment register gs_base")); + } + } +#endif } - - if (clear_status || lwp->stopped_by_watchpoint) - x86_linux_dr_set (lwp->ptid, DR_STATUS, 0); -} - -static void -x86_linux_new_thread (struct lwp_info *lp) -{ - struct arch_lwp_info *info = XCNEW (struct arch_lwp_info); - - info->debug_registers_changed = 1; - - lp->arch_private = info; } - -/* linux_nat_new_fork hook. */ - -static void -x86_linux_new_fork (struct lwp_info *parent, pid_t child_pid) -{ - pid_t parent_pid; - struct i386_debug_reg_state *parent_state; - struct i386_debug_reg_state *child_state; - - /* NULL means no watchpoint has ever been set in the parent. In - that case, there's nothing to do. */ - if (parent->arch_private == NULL) - return; - - /* Linux kernel before 2.6.33 commit - 72f674d203cd230426437cdcf7dd6f681dad8b0d - will inherit hardware debug registers from parent - on fork/vfork/clone. Newer Linux kernels create such tasks with - zeroed debug registers. - - GDB core assumes the child inherits the watchpoints/hw - breakpoints of the parent, and will remove them all from the - forked off process. Copy the debug registers mirrors into the - new process so that all breakpoints and watchpoints can be - removed together. The debug registers mirror will become zeroed - in the end before detaching the forked off process, thus making - this compatible with older Linux kernels too. */ - - parent_pid = ptid_get_pid (parent->ptid); - parent_state = i386_debug_reg_state (parent_pid); - child_state = i386_debug_reg_state (child_pid); - *child_state = *parent_state; -} - /* This function is called by libthread_db as part of its handling of a request for a thread's local storage address. */ ps_err_e -ps_get_thread_area (const struct ps_prochandle *ph, +ps_get_thread_area (struct ps_prochandle *ph, lwpid_t lwpid, int idx, void **base) { if (gdbarch_bfd_arch_info (target_gdbarch ())->bits_per_word == 32) { - /* The full structure is found in . The second - integer is the LDT's base_address and that is used to locate - the thread's local storage. See i386-linux-nat.c more - info. */ - unsigned int desc[4]; - - /* This code assumes that "int" is 32 bits and that - GET_THREAD_AREA returns no more than 4 int values. */ - gdb_assert (sizeof (int) == 4); -#ifndef PTRACE_GET_THREAD_AREA -#define PTRACE_GET_THREAD_AREA 25 -#endif - if (ptrace (PTRACE_GET_THREAD_AREA, - lwpid, (void *) (long) idx, (unsigned long) &desc) < 0) - return PS_ERR; - - /* Extend the value to 64 bits. Here it's assumed that a "long" - and a "void *" are the same. */ - (*base) = (void *) (long) desc[1]; - return PS_OK; + unsigned int base_addr; + ps_err_e result; + + result = x86_linux_get_thread_area (lwpid, (void *) (long) idx, + &base_addr); + if (result == PS_OK) + { + /* Extend the value to 64 bits. Here it's assumed that + a "long" and a "void *" are the same. */ + (*base) = (void *) (long) base_addr; + } + return result; } else { - /* This definition comes from prctl.h, but some kernels may not - have it. */ -#ifndef PTRACE_ARCH_PRCTL -#define PTRACE_ARCH_PRCTL 30 -#endif + /* FIXME: ezannoni-2003-07-09 see comment above about include file order. We could be getting bogus values for these two. */ gdb_assert (FS < ELF_NGREG); @@ -578,657 +452,35 @@ ps_get_thread_area (const struct ps_prochandle *ph, } -static void (*super_post_startup_inferior) (struct target_ops *self, - ptid_t ptid); - -static void -x86_linux_child_post_startup_inferior (struct target_ops *self, ptid_t ptid) -{ - i386_cleanup_dregs (); - super_post_startup_inferior (self, ptid); -} - - -/* When GDB is built as a 64-bit application on linux, the - PTRACE_GETSIGINFO data is always presented in 64-bit layout. Since - debugging a 32-bit inferior with a 64-bit GDB should look the same - as debugging it with a 32-bit GDB, we do the 32-bit <-> 64-bit - conversion in-place ourselves. */ - -/* These types below (compat_*) define a siginfo type that is layout - compatible with the siginfo type exported by the 32-bit userspace - support. */ - -typedef int compat_int_t; -typedef unsigned int compat_uptr_t; - -typedef int compat_time_t; -typedef int compat_timer_t; -typedef int compat_clock_t; - -struct compat_timeval -{ - compat_time_t tv_sec; - int tv_usec; -}; - -typedef union compat_sigval -{ - compat_int_t sival_int; - compat_uptr_t sival_ptr; -} compat_sigval_t; - -typedef struct compat_siginfo -{ - int si_signo; - int si_errno; - int si_code; - - union - { - int _pad[((128 / sizeof (int)) - 3)]; - - /* kill() */ - struct - { - unsigned int _pid; - unsigned int _uid; - } _kill; - - /* POSIX.1b timers */ - struct - { - compat_timer_t _tid; - int _overrun; - compat_sigval_t _sigval; - } _timer; - - /* POSIX.1b signals */ - struct - { - unsigned int _pid; - unsigned int _uid; - compat_sigval_t _sigval; - } _rt; - - /* SIGCHLD */ - struct - { - unsigned int _pid; - unsigned int _uid; - int _status; - compat_clock_t _utime; - compat_clock_t _stime; - } _sigchld; - - /* SIGILL, SIGFPE, SIGSEGV, SIGBUS */ - struct - { - unsigned int _addr; - } _sigfault; - - /* SIGPOLL */ - struct - { - int _band; - int _fd; - } _sigpoll; - } _sifields; -} compat_siginfo_t; - -/* For x32, clock_t in _sigchld is 64bit aligned at 4 bytes. */ -typedef struct compat_x32_clock -{ - int lower; - int upper; -} compat_x32_clock_t; - -typedef struct compat_x32_siginfo -{ - int si_signo; - int si_errno; - int si_code; - - union - { - int _pad[((128 / sizeof (int)) - 3)]; - - /* kill() */ - struct - { - unsigned int _pid; - unsigned int _uid; - } _kill; - - /* POSIX.1b timers */ - struct - { - compat_timer_t _tid; - int _overrun; - compat_sigval_t _sigval; - } _timer; - - /* POSIX.1b signals */ - struct - { - unsigned int _pid; - unsigned int _uid; - compat_sigval_t _sigval; - } _rt; - - /* SIGCHLD */ - struct - { - unsigned int _pid; - unsigned int _uid; - int _status; - compat_x32_clock_t _utime; - compat_x32_clock_t _stime; - } _sigchld; - - /* SIGILL, SIGFPE, SIGSEGV, SIGBUS */ - struct - { - unsigned int _addr; - } _sigfault; - - /* SIGPOLL */ - struct - { - int _band; - int _fd; - } _sigpoll; - } _sifields; -} compat_x32_siginfo_t; - -#define cpt_si_pid _sifields._kill._pid -#define cpt_si_uid _sifields._kill._uid -#define cpt_si_timerid _sifields._timer._tid -#define cpt_si_overrun _sifields._timer._overrun -#define cpt_si_status _sifields._sigchld._status -#define cpt_si_utime _sifields._sigchld._utime -#define cpt_si_stime _sifields._sigchld._stime -#define cpt_si_ptr _sifields._rt._sigval.sival_ptr -#define cpt_si_addr _sifields._sigfault._addr -#define cpt_si_band _sifields._sigpoll._band -#define cpt_si_fd _sifields._sigpoll._fd - -/* glibc at least up to 2.3.2 doesn't have si_timerid, si_overrun. - In their place is si_timer1,si_timer2. */ -#ifndef si_timerid -#define si_timerid si_timer1 -#endif -#ifndef si_overrun -#define si_overrun si_timer2 -#endif - -static void -compat_siginfo_from_siginfo (compat_siginfo_t *to, siginfo_t *from) -{ - memset (to, 0, sizeof (*to)); - - to->si_signo = from->si_signo; - to->si_errno = from->si_errno; - to->si_code = from->si_code; - - if (to->si_code == SI_TIMER) - { - to->cpt_si_timerid = from->si_timerid; - to->cpt_si_overrun = from->si_overrun; - to->cpt_si_ptr = (intptr_t) from->si_ptr; - } - else if (to->si_code == SI_USER) - { - to->cpt_si_pid = from->si_pid; - to->cpt_si_uid = from->si_uid; - } - else if (to->si_code < 0) - { - to->cpt_si_pid = from->si_pid; - to->cpt_si_uid = from->si_uid; - to->cpt_si_ptr = (intptr_t) from->si_ptr; - } - else - { - switch (to->si_signo) - { - case SIGCHLD: - to->cpt_si_pid = from->si_pid; - to->cpt_si_uid = from->si_uid; - to->cpt_si_status = from->si_status; - to->cpt_si_utime = from->si_utime; - to->cpt_si_stime = from->si_stime; - break; - case SIGILL: - case SIGFPE: - case SIGSEGV: - case SIGBUS: - to->cpt_si_addr = (intptr_t) from->si_addr; - break; - case SIGPOLL: - to->cpt_si_band = from->si_band; - to->cpt_si_fd = from->si_fd; - break; - default: - to->cpt_si_pid = from->si_pid; - to->cpt_si_uid = from->si_uid; - to->cpt_si_ptr = (intptr_t) from->si_ptr; - break; - } - } -} - -static void -siginfo_from_compat_siginfo (siginfo_t *to, compat_siginfo_t *from) -{ - memset (to, 0, sizeof (*to)); - - to->si_signo = from->si_signo; - to->si_errno = from->si_errno; - to->si_code = from->si_code; - - if (to->si_code == SI_TIMER) - { - to->si_timerid = from->cpt_si_timerid; - to->si_overrun = from->cpt_si_overrun; - to->si_ptr = (void *) (intptr_t) from->cpt_si_ptr; - } - else if (to->si_code == SI_USER) - { - to->si_pid = from->cpt_si_pid; - to->si_uid = from->cpt_si_uid; - } - if (to->si_code < 0) - { - to->si_pid = from->cpt_si_pid; - to->si_uid = from->cpt_si_uid; - to->si_ptr = (void *) (intptr_t) from->cpt_si_ptr; - } - else - { - switch (to->si_signo) - { - case SIGCHLD: - to->si_pid = from->cpt_si_pid; - to->si_uid = from->cpt_si_uid; - to->si_status = from->cpt_si_status; - to->si_utime = from->cpt_si_utime; - to->si_stime = from->cpt_si_stime; - break; - case SIGILL: - case SIGFPE: - case SIGSEGV: - case SIGBUS: - to->si_addr = (void *) (intptr_t) from->cpt_si_addr; - break; - case SIGPOLL: - to->si_band = from->cpt_si_band; - to->si_fd = from->cpt_si_fd; - break; - default: - to->si_pid = from->cpt_si_pid; - to->si_uid = from->cpt_si_uid; - to->si_ptr = (void* ) (intptr_t) from->cpt_si_ptr; - break; - } - } -} - -static void -compat_x32_siginfo_from_siginfo (compat_x32_siginfo_t *to, - siginfo_t *from) -{ - memset (to, 0, sizeof (*to)); - - to->si_signo = from->si_signo; - to->si_errno = from->si_errno; - to->si_code = from->si_code; - - if (to->si_code == SI_TIMER) - { - to->cpt_si_timerid = from->si_timerid; - to->cpt_si_overrun = from->si_overrun; - to->cpt_si_ptr = (intptr_t) from->si_ptr; - } - else if (to->si_code == SI_USER) - { - to->cpt_si_pid = from->si_pid; - to->cpt_si_uid = from->si_uid; - } - else if (to->si_code < 0) - { - to->cpt_si_pid = from->si_pid; - to->cpt_si_uid = from->si_uid; - to->cpt_si_ptr = (intptr_t) from->si_ptr; - } - else - { - switch (to->si_signo) - { - case SIGCHLD: - to->cpt_si_pid = from->si_pid; - to->cpt_si_uid = from->si_uid; - to->cpt_si_status = from->si_status; - memcpy (&to->cpt_si_utime, &from->si_utime, - sizeof (to->cpt_si_utime)); - memcpy (&to->cpt_si_stime, &from->si_stime, - sizeof (to->cpt_si_stime)); - break; - case SIGILL: - case SIGFPE: - case SIGSEGV: - case SIGBUS: - to->cpt_si_addr = (intptr_t) from->si_addr; - break; - case SIGPOLL: - to->cpt_si_band = from->si_band; - to->cpt_si_fd = from->si_fd; - break; - default: - to->cpt_si_pid = from->si_pid; - to->cpt_si_uid = from->si_uid; - to->cpt_si_ptr = (intptr_t) from->si_ptr; - break; - } - } -} - -static void -siginfo_from_compat_x32_siginfo (siginfo_t *to, - compat_x32_siginfo_t *from) -{ - memset (to, 0, sizeof (*to)); - - to->si_signo = from->si_signo; - to->si_errno = from->si_errno; - to->si_code = from->si_code; - - if (to->si_code == SI_TIMER) - { - to->si_timerid = from->cpt_si_timerid; - to->si_overrun = from->cpt_si_overrun; - to->si_ptr = (void *) (intptr_t) from->cpt_si_ptr; - } - else if (to->si_code == SI_USER) - { - to->si_pid = from->cpt_si_pid; - to->si_uid = from->cpt_si_uid; - } - if (to->si_code < 0) - { - to->si_pid = from->cpt_si_pid; - to->si_uid = from->cpt_si_uid; - to->si_ptr = (void *) (intptr_t) from->cpt_si_ptr; - } - else - { - switch (to->si_signo) - { - case SIGCHLD: - to->si_pid = from->cpt_si_pid; - to->si_uid = from->cpt_si_uid; - to->si_status = from->cpt_si_status; - memcpy (&to->si_utime, &from->cpt_si_utime, - sizeof (to->si_utime)); - memcpy (&to->si_stime, &from->cpt_si_stime, - sizeof (to->si_stime)); - break; - case SIGILL: - case SIGFPE: - case SIGSEGV: - case SIGBUS: - to->si_addr = (void *) (intptr_t) from->cpt_si_addr; - break; - case SIGPOLL: - to->si_band = from->cpt_si_band; - to->si_fd = from->cpt_si_fd; - break; - default: - to->si_pid = from->cpt_si_pid; - to->si_uid = from->cpt_si_uid; - to->si_ptr = (void* ) (intptr_t) from->cpt_si_ptr; - break; - } - } -} - -/* Convert a native/host siginfo object, into/from the siginfo in the +/* Convert a ptrace/host siginfo object, into/from the siginfo in the layout of the inferiors' architecture. Returns true if any conversion was done; false otherwise. If DIRECTION is 1, then copy - from INF to NATIVE. If DIRECTION is 0, copy from NATIVE to + from INF to PTRACE. If DIRECTION is 0, copy from PTRACE to INF. */ -static int -amd64_linux_siginfo_fixup (siginfo_t *native, gdb_byte *inf, int direction) +bool +amd64_linux_nat_target::low_siginfo_fixup (siginfo_t *ptrace, + gdb_byte *inf, + int direction) { struct gdbarch *gdbarch = get_frame_arch (get_current_frame ()); /* Is the inferior 32-bit? If so, then do fixup the siginfo object. */ if (gdbarch_bfd_arch_info (gdbarch)->bits_per_word == 32) - { - gdb_assert (sizeof (siginfo_t) == sizeof (compat_siginfo_t)); - - if (direction == 0) - compat_siginfo_from_siginfo ((struct compat_siginfo *) inf, native); - else - siginfo_from_compat_siginfo (native, (struct compat_siginfo *) inf); - - return 1; - } + return amd64_linux_siginfo_fixup_common (ptrace, inf, direction, + FIXUP_32); /* No fixup for native x32 GDB. */ else if (gdbarch_addr_bit (gdbarch) == 32 && sizeof (void *) == 8) - { - gdb_assert (sizeof (siginfo_t) == sizeof (compat_x32_siginfo_t)); - - if (direction == 0) - compat_x32_siginfo_from_siginfo ((struct compat_x32_siginfo *) inf, - native); - else - siginfo_from_compat_x32_siginfo (native, - (struct compat_x32_siginfo *) inf); - - return 1; - } - else - return 0; -} - -/* Get Linux/x86 target description from running target. - - Value of CS segment register: - 1. 64bit process: 0x33. - 2. 32bit process: 0x23. - - Value of DS segment register: - 1. LP64 process: 0x0. - 2. X32 process: 0x2b. - */ - -#define AMD64_LINUX_USER64_CS 0x33 -#define AMD64_LINUX_X32_DS 0x2b - -static const struct target_desc * -amd64_linux_read_description (struct target_ops *ops) -{ - unsigned long cs; - unsigned long ds; - int tid; - int is_64bit; - int is_x32; - static uint64_t xcr0; - - /* GNU/Linux LWP ID's are process ID's. */ - tid = ptid_get_lwp (inferior_ptid); - if (tid == 0) - tid = ptid_get_pid (inferior_ptid); /* Not a threaded program. */ - - /* Get CS register. */ - errno = 0; - cs = ptrace (PTRACE_PEEKUSER, tid, - offsetof (struct user_regs_struct, cs), 0); - if (errno != 0) - perror_with_name (_("Couldn't get CS register")); - - is_64bit = cs == AMD64_LINUX_USER64_CS; - - /* Get DS register. */ - errno = 0; - ds = ptrace (PTRACE_PEEKUSER, tid, - offsetof (struct user_regs_struct, ds), 0); - if (errno != 0) - perror_with_name (_("Couldn't get DS register")); - - is_x32 = ds == AMD64_LINUX_X32_DS; - - if (sizeof (void *) == 4 && is_64bit && !is_x32) - error (_("Can't debug 64-bit process with 32-bit GDB")); - - if (have_ptrace_getregset == -1) - { - uint64_t xstateregs[(I386_XSTATE_SSE_SIZE / sizeof (uint64_t))]; - struct iovec iov; - - iov.iov_base = xstateregs; - iov.iov_len = sizeof (xstateregs); - - /* Check if PTRACE_GETREGSET works. */ - if (ptrace (PTRACE_GETREGSET, tid, - (unsigned int) NT_X86_XSTATE, (long) &iov) < 0) - have_ptrace_getregset = 0; - else - { - have_ptrace_getregset = 1; - - /* Get XCR0 from XSAVE extended state. */ - xcr0 = xstateregs[(I386_LINUX_XSAVE_XCR0_OFFSET - / sizeof (uint64_t))]; - } - } - - /* Check the native XCR0 only if PTRACE_GETREGSET is available. */ - if (have_ptrace_getregset && (xcr0 & I386_XSTATE_ALL_MASK)) - { - switch (xcr0 & I386_XSTATE_ALL_MASK) - { - case I386_XSTATE_MPX_AVX512_MASK: - case I386_XSTATE_AVX512_MASK: - if (is_64bit) - { - if (is_x32) - return tdesc_x32_avx512_linux; - else - return tdesc_amd64_avx512_linux; - } - else - return tdesc_i386_avx512_linux; - case I386_XSTATE_MPX_MASK: - if (is_64bit) - { - if (is_x32) - return tdesc_x32_avx_linux; /* No MPX on x32 using AVX. */ - else - return tdesc_amd64_mpx_linux; - } - else - return tdesc_i386_mpx_linux; - case I386_XSTATE_AVX_MASK: - if (is_64bit) - { - if (is_x32) - return tdesc_x32_avx_linux; - else - return tdesc_amd64_avx_linux; - } - else - return tdesc_i386_avx_linux; - default: - if (is_64bit) - { - if (is_x32) - return tdesc_x32_linux; - else - return tdesc_amd64_linux; - } - else - return tdesc_i386_linux; - } - } + return amd64_linux_siginfo_fixup_common (ptrace, inf, direction, + FIXUP_X32); else - { - if (is_64bit) - { - if (is_x32) - return tdesc_x32_linux; - else - return tdesc_amd64_linux; - } - else - return tdesc_i386_linux; - } -} - -/* Enable branch tracing. */ - -static struct btrace_target_info * -x86_linux_enable_btrace (struct target_ops *self, ptid_t ptid) -{ - struct btrace_target_info *tinfo; - struct gdbarch *gdbarch; - - errno = 0; - tinfo = linux_enable_btrace (ptid); - - if (tinfo == NULL) - error (_("Could not enable branch tracing for %s: %s."), - target_pid_to_str (ptid), safe_strerror (errno)); - - /* Fill in the size of a pointer in bits. */ - gdbarch = target_thread_architecture (ptid); - tinfo->ptr_bits = gdbarch_ptr_bit (gdbarch); - - return tinfo; + return false; } -/* Disable branch tracing. */ - -static void -x86_linux_disable_btrace (struct target_ops *self, - struct btrace_target_info *tinfo) -{ - enum btrace_error errcode = linux_disable_btrace (tinfo); - - if (errcode != BTRACE_ERR_NONE) - error (_("Could not disable branch tracing.")); -} - -/* Teardown branch tracing. */ - -static void -x86_linux_teardown_btrace (struct target_ops *self, - struct btrace_target_info *tinfo) -{ - /* Ignore errors. */ - linux_disable_btrace (tinfo); -} - -static enum btrace_error -x86_linux_read_btrace (struct target_ops *self, - VEC (btrace_block_s) **data, - struct btrace_target_info *btinfo, - enum btrace_read_type type) -{ - return linux_read_btrace (data, btinfo, type); -} - -/* Provide a prototype to silence -Wmissing-prototypes. */ -void _initialize_amd64_linux_nat (void); - void _initialize_amd64_linux_nat (void) { - struct target_ops *t; - amd64_native_gregset32_reg_offset = amd64_linux_gregset32_reg_offset; amd64_native_gregset32_num_regs = I386_LINUX_NUM_REGS; amd64_native_gregset64_reg_offset = amd64_linux_gregset_reg_offset; @@ -1237,40 +489,8 @@ _initialize_amd64_linux_nat (void) gdb_assert (ARRAY_SIZE (amd64_linux_gregset32_reg_offset) == amd64_native_gregset32_num_regs); - /* Fill in the generic GNU/Linux methods. */ - t = linux_target (); - - i386_use_watchpoints (t); - - i386_dr_low.set_control = x86_linux_dr_set_control; - i386_dr_low.set_addr = x86_linux_dr_set_addr; - i386_dr_low.get_addr = x86_linux_dr_get_addr; - i386_dr_low.get_status = x86_linux_dr_get_status; - i386_dr_low.get_control = x86_linux_dr_get_control; - i386_set_debug_register_length (8); + linux_target = &the_amd64_linux_nat_target; - /* Override the GNU/Linux inferior startup hook. */ - super_post_startup_inferior = t->to_post_startup_inferior; - t->to_post_startup_inferior = x86_linux_child_post_startup_inferior; - - /* Add our register access methods. */ - t->to_fetch_registers = amd64_linux_fetch_inferior_registers; - t->to_store_registers = amd64_linux_store_inferior_registers; - - t->to_read_description = amd64_linux_read_description; - - /* Add btrace methods. */ - t->to_supports_btrace = linux_supports_btrace; - t->to_enable_btrace = x86_linux_enable_btrace; - t->to_disable_btrace = x86_linux_disable_btrace; - t->to_teardown_btrace = x86_linux_teardown_btrace; - t->to_read_btrace = x86_linux_read_btrace; - - /* Register the target. */ - linux_nat_add_target (t); - linux_nat_set_new_thread (t, x86_linux_new_thread); - linux_nat_set_new_fork (t, x86_linux_new_fork); - linux_nat_set_forget_process (t, i386_forget_process); - linux_nat_set_siginfo_fixup (t, amd64_linux_siginfo_fixup); - linux_nat_set_prepare_to_resume (t, x86_linux_prepare_to_resume); + /* Add the target. */ + add_inf_child_target (linux_target); }