mirrors/binutils-gdb
1
0
Fork 0
mirror of https://sourceware.org/git/binutils-gdb.git synced 2024-11-24 10:35:12 +08:00
Code Issues Actions Packages Projects Releases Wiki Activity

FreeBSD x86: Remove fallback for detecting signal trampolines by address.

Browse Source 
A few FreeBSD releases did not include the page holding the signal
code in core dumps.  As a workaround, a sysctl was used to fetch the
default location of the signal code instead.  The youngest affected
FreeBSD release is 10.1 released in November 2014 and EOLed in
December 2016.  The fallback only works for native processes and would
require a separate unwinder once the FreeBSD arches are converted to
use tramp_frame for signal frames.
This commit is contained in:
John Baldwin 2022-01-28 11:14:37 -08:00
parent bf84b776bd
commit 5046f3c8c0
6 changed files with 0 additions and 72 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

28
gdb/amd64-fbsd-nat.c
View File

@ -278,32 +278,4 @@ Please report this to <bug-gdb@gnu.org>."),
}
SC_RBP_OFFSET = offset;
#ifdef KERN_PROC_SIGTRAMP
/* Normally signal frames are detected via amd64fbsd_sigtramp_p.
However, FreeBSD 9.2 through 10.1 do not include the page holding
the signal code in core dumps. These releases do provide a
kern.proc.sigtramp.<pid> sysctl that returns the location of the
signal trampoline for a running process. We fetch the location
of the current (gdb) process and use this to identify signal
frames in core dumps from these releases. Note that this only
works for core dumps of 64-bit (FreeBSD/amd64) processes and does
not handle core dumps of 32-bit (FreeBSD/i386) processes. */
{
int mib[4];
struct kinfo_sigtramp kst;
size_t len;
mib[0] = CTL_KERN;
mib[1] = KERN_PROC;
mib[2] = KERN_PROC_SIGTRAMP;
mib[3] = getpid ();
len = sizeof (kst);
if (sysctl (mib, 4, &kst, &len, NULL, 0) == 0)
{
amd64fbsd_sigtramp_start_addr = (uintptr_t) kst.ksigtramp_start;
amd64fbsd_sigtramp_end_addr = (uintptr_t) kst.ksigtramp_end;
}
}
#endif
}

6
gdb/amd64-fbsd-tdep.c
View File

@ -117,10 +117,6 @@ static int amd64fbsd_r_reg_offset[] =
-1 /* %gs */
};
/* Location of the signal trampoline. */
CORE_ADDR amd64fbsd_sigtramp_start_addr;
CORE_ADDR amd64fbsd_sigtramp_end_addr;
/* From <machine/signal.h>. */
int amd64fbsd_sc_reg_offset[] =
{
@ -245,8 +241,6 @@ amd64fbsd_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
amd64_target_description (X86_XSTATE_SSE_MASK, true));
tdep->sigtramp_p = amd64fbsd_sigtramp_p;
tdep->sigtramp_start = amd64fbsd_sigtramp_start_addr;
tdep->sigtramp_end = amd64fbsd_sigtramp_end_addr;
tdep->sigcontext_addr = amd64fbsd_sigcontext_addr;
tdep->sc_reg_offset = amd64fbsd_sc_reg_offset;
tdep->sc_num_regs = ARRAY_SIZE (amd64fbsd_sc_reg_offset);

2
gdb/amd64-tdep.h
View File

@ -145,8 +145,6 @@ extern int amd64nbsd_r_reg_offset[];
extern int amd64obsd_r_reg_offset[];
/* Variables exported from amd64-fbsd-tdep.c. */
extern CORE_ADDR amd64fbsd_sigtramp_start_addr;
extern CORE_ADDR amd64fbsd_sigtramp_end_addr;
extern int amd64fbsd_sc_reg_offset[];
#endif /* amd64-tdep.h */

26
gdb/i386-fbsd-nat.c
View File

@ -182,30 +182,4 @@ _initialize_i386fbsd_nat ()
/* Support debugging kernel virtual memory images. */
bsd_kvm_add_target (i386fbsd_supply_pcb);
#ifdef KERN_PROC_SIGTRAMP
/* Normally signal frames are detected via i386fbsd_sigtramp_p.
However, FreeBSD 9.2 through 10.1 do not include the page holding
the signal code in core dumps. These releases do provide a
kern.proc.sigtramp.<pid> sysctl that returns the location of the
signal trampoline for a running process. We fetch the location
of the current (gdb) process and use this to identify signal
frames in core dumps from these releases. */
{
int mib[4];
struct kinfo_sigtramp kst;
size_t len;
mib[0] = CTL_KERN;
mib[1] = KERN_PROC;
mib[2] = KERN_PROC_SIGTRAMP;
mib[3] = getpid ();
len = sizeof (kst);
if (sysctl (mib, 4, &kst, &len, NULL, 0) == 0)
{
i386fbsd_sigtramp_start_addr = (uintptr_t) kst.ksigtramp_start;
i386fbsd_sigtramp_end_addr = (uintptr_t) kst.ksigtramp_end;
}
}
#endif
}

8
gdb/i386-fbsd-tdep.c
View File

@ -122,10 +122,6 @@ static int i386fbsd_r_reg_offset[] =
2 * 4, 1 * 4, 0 * 4, 18 * 4 /* %ds, %es, %fs, %gs */
};
/* Sigtramp routine location. */
CORE_ADDR i386fbsd_sigtramp_start_addr;
CORE_ADDR i386fbsd_sigtramp_end_addr;
/* From <machine/signal.h>. */
int i386fbsd_sc_reg_offset[] =
{
@ -292,10 +288,6 @@ i386fbsd_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
tdep->sigtramp_p = i386fbsd_sigtramp_p;
/* FreeBSD uses a different memory layout. */
tdep->sigtramp_start = i386fbsd_sigtramp_start_addr;
tdep->sigtramp_end = i386fbsd_sigtramp_end_addr;
/* FreeBSD has a more complete `struct sigcontext'. */
tdep->sc_reg_offset = i386fbsd_sc_reg_offset;
tdep->sc_num_regs = ARRAY_SIZE (i386fbsd_sc_reg_offset);

2
gdb/i386-tdep.h
View File

@ -472,8 +472,6 @@ extern int i386_mpx_enabled (void);
/* Functions and variables exported from i386-bsd-tdep.c. */
extern void i386bsd_init_abi (struct gdbarch_info, struct gdbarch *);
extern CORE_ADDR i386fbsd_sigtramp_start_addr;
extern CORE_ADDR i386fbsd_sigtramp_end_addr;
extern CORE_ADDR i386obsd_sigtramp_start_addr;
extern CORE_ADDR i386obsd_sigtramp_end_addr;
extern int i386fbsd_sc_reg_offset[];