linux/include/asm-sparc64
David S. Miller 28e6103665 sparc: Fix debugger syscall restart interactions.
So, forever, we've had this ptrace_signal_deliver implementation
which tries to handle all of the nasties that can occur when the
debugger looks at a process about to take a signal.  It's meant
to address all of these issues inside of the kernel so that the
debugger need not be mindful of such things.

Problem is, this doesn't work.

The idea was that we should do the syscall restart business first, so
that the debugger captures that state.  Otherwise, if the debugger for
example saves the child's state, makes the child execute something
else, then restores the saved state, we won't handle the syscall
restart properly because we lose the "we're in a syscall" state.

The code here worked for most cases, but if the debugger actually
passes the signal through to the child unaltered, it's possible that
we would do a syscall restart when we shouldn't have.

In particular this breaks the case of debugging a process under a gdb
which is being debugged by yet another gdb.  gdb uses sigsuspend
to wait for SIGCHLD of the inferior, but if gdb itself is being
debugged by a top-level gdb we get a ptrace_stop().  The top-level gdb
does a PTRACE_CONT with SIGCHLD to let the inferior gdb see the
signal.  But ptrace_signal_deliver() assumed the debugger would cancel
out the signal and therefore did a syscall restart, because the return
error was ERESTARTNOHAND.

Fix this by simply making ptrace_signal_deliver() a nop, and providing
a way for the debugger to control system call restarting properly:

1) Report a "in syscall" software bit in regs->{tstate,psr}.
   It is set early on in trap entry to a system call and is fully
   visible to the debugger via ptrace() and regsets.

2) Test this bit right before doing a syscall restart.  We have
   to do a final recheck right after get_signal_to_deliver() in
   case the debugger cleared the bit during ptrace_stop().

3) Clear the bit in trap return so we don't accidently try to set
   that bit in the real register.

As a result we also get a ptrace_{is,clear}_syscall() for sparc32 just
like sparc64 has.

M68K has this same exact bug, and is now the only other user of the
ptrace_signal_deliver hook.  It needs to be fixed in the same exact
way as sparc.

Signed-off-by: David S. Miller <davem@davemloft.net>
2008-05-11 02:07:19 -07:00
..
agp.h x86: remove flush_agp_mappings() 2008-01-30 13:34:07 +01:00
apb.h
asi.h [SPARC64]: Sun4v specific ASI defines. 2006-03-20 01:11:43 -08:00
atomic.h [SPARC64]: __inline__ --> inline 2007-10-27 00:13:04 -07:00
auxio.h
auxvec.h [SPARC]: Merge include/asm-sparc{,64}/auxvec.h 2008-02-09 04:00:03 -08:00
backoff.h [SPARC64]: Fix atomic backoff limit. 2008-03-19 01:04:48 -07:00
bbc.h
bitops.h generic: implement __fls on all 64-bit archs 2008-04-26 19:21:16 +02:00
bpp.h [SPARC]: Merge asm-sparc{,64}/bpp.h 2008-02-09 04:00:12 -08:00
bug.h [SPARC]: Merge asm-sparc{,64}/bug.h 2008-02-09 04:00:32 -08:00
bugs.h [SPARC]: Merge asm-sparc{,64}/bugs.h 2008-02-09 04:00:37 -08:00
byteorder.h [SPARC]: Merge asm-sparc{,64}/byteorder.h 2008-02-09 04:17:28 -08:00
cache.h [SPARC]: Merge asm-sparc{,64}/cache.h 2008-02-09 04:17:37 -08:00
cacheflush.h [PATCH] Optimize D-cache alias handling on fork 2006-12-13 09:27:08 -08:00
chafsr.h
checksum.h [NET]: SPARC64 checksum annotations and cleanups. 2006-12-02 21:23:23 -08:00
chmctrl.h
cmt.h
compat_signal.h Remove all inclusions of <linux/config.h> 2006-10-04 03:38:54 -04:00
compat.h asm-*/compat.h: fix typo in comment 2008-02-03 16:32:51 +02:00
cpudata.h [SPARC64]: Fix sparse warnings in arch/sparc64/kernel/{cpu,setup}.c 2008-03-25 21:51:40 -07:00
cputime.h [SPARC]: Merge asm-sparc{,64}/cputime.h 2008-02-09 04:17:47 -08:00
current.h [SPARC]: Merge asm-sparc{,64}/current.h 2008-02-09 04:17:54 -08:00
dcr.h
dcu.h [SPARC64]: Fix sparse errors in arch/sparc64/kernel/traps.c 2008-03-26 00:19:43 -07:00
delay.h [SPARC64]: More sensible udelay implementation. 2007-07-16 04:05:02 -07:00
device.h [SPARC]: Merge asm-sparc{,64}/device.h 2008-02-09 04:18:02 -08:00
display7seg.h
div64.h [SPARC]: Merge asm-sparc{,64}/div64.h 2008-02-09 04:18:08 -08:00
dma-mapping.h [SPARC64]: Fix OOPS in dma_sync_*_for_device() 2007-12-20 01:29:45 -08:00
dma.h [SPARC64]: Fix floppy build failure. 2007-03-05 13:22:28 -08:00
ebus.h [SPARC64] ebus: Convert to use pci_device_to_OF_node(). 2007-04-26 01:55:04 -07:00
elf.h [SPARC64]: Make use of the new fs/compat_binfmt_elf.c 2008-02-08 00:08:10 -08:00
emergency-restart.h [SPARC]: Merge asm-sparc{,64}/emergency-restart.h 2008-02-09 04:18:14 -08:00
envctrl.h
errno.h [SPARC]: Merge asm-sparc{,64}/errno.h 2008-02-09 04:18:23 -08:00
estate.h
fb.h [SPARC]: Merge asm-sparc{,64}/fb.h 2008-02-09 04:18:29 -08:00
fbio.h [SPARC]: Mark SBUS framebuffer ioctls as IGNORE in compat_ioctl.c 2007-07-30 00:27:36 -07:00
fcntl.h [SPARC]: Fix O_CLOEXEC values. 2007-08-03 14:24:17 -07:00
fhc.h [SPARC64]: Convert central bus layer to in-kernel PROM device tree. 2006-06-23 23:15:32 -07:00
floppy.h sparc64: Kill unused local ISA bus layer. 2008-04-26 21:41:23 -07:00
fpumacro.h [SPARC64]: __inline__ --> inline 2007-10-27 00:13:04 -07:00
futex.h asm-*/futex.h should include linux/uaccess.h 2008-04-30 08:29:52 -07:00
hardirq.h [SPARC64]: Move over to GENERIC_HARDIRQS. 2006-06-20 01:23:32 -07:00
head.h [SPARC64]: Add GET_GL_GLOBAL() macro for SUN4V. 2006-03-20 01:13:18 -08:00
hugetlb.h hugetlbfs: common code update for s390 2008-04-28 08:58:25 -07:00
hvtramp.h [SPARC64]: Remove most limitations to kernel image size. 2008-03-21 17:01:38 -07:00
hw_irq.h [SPARC64]: Minor irq handling cleanups. 2006-12-17 14:06:56 -08:00
hypervisor.h [SPARC64]: Fix two kernel linear mapping setup bugs. 2007-12-13 06:13:38 -08:00
ide.h ide: remove ide_default_io_ctl() macro 2008-04-18 00:46:34 +02:00
idprom.h [SPARC]: Clean up idprom header files. 2006-03-20 01:12:08 -08:00
intr_queue.h [SPARC64]: Sun4v interrupt queue register definitions. 2006-03-20 01:11:44 -08:00
io.h [SPARC64]: Add SG merging support back into IOMMU code. 2008-02-09 03:15:36 -08:00
ioctl.h
ioctls.h [SPARC]: Remove SunOS and Solaris binary support. 2008-04-21 15:10:15 -07:00
iommu.h [SPARC64]: NUMA device infrastructure. 2008-04-23 23:32:16 -07:00
ipcbuf.h
irq_regs.h [PATCH] sparc64 pt_regs fixes 2006-10-08 12:32:35 -07:00
irq.h [SPARC64]: Fix sparse warnings in arch/sparc64/kernel/irq.c 2008-03-26 00:37:51 -07:00
irqflags.h [SPARC64]: Add irqtrace/stacktrace/lockdep support. 2006-12-10 02:39:09 -08:00
Kbuild [SPARC]: Remove SunOS and Solaris binary support. 2008-04-21 15:10:15 -07:00
kdebug.h x86: optimize page faults like all other achitectures and kill notifier cruft 2007-10-16 09:42:50 -07:00
kgdb.h sparc: Add kgdb support. 2008-04-29 02:38:50 -07:00
kmap_types.h
kprobes.h Kprobes: indicate kretprobe support in Kconfig 2008-03-04 16:35:11 -08:00
kvm.h kvm: provide kvm.h for all architecture: fixes headers_install 2008-04-02 15:28:18 -07:00
ldc.h [SPARC64]: Fix build regressions added by dr-cpu changes. 2007-07-16 04:04:49 -07:00
linkage.h
lmb.h [LIB]: Make PowerPC LMB code generic so sparc64 can use it too. 2008-02-13 16:56:49 -08:00
local.h local_t: sparc64 cleanup 2007-05-08 11:15:20 -07:00
lsu.h consolidate asm/const.h to linux/const.h 2007-05-08 11:15:13 -07:00
mc146818rtc.h Don't include linux/config.h from anywhere else in include/ 2006-04-26 12:56:16 +01:00
mdesc.h [SPARC64]: Add basic infrastructure for MD add/remove notification. 2007-07-18 01:19:51 -07:00
mman.h [SPARC]: Remove SunOS and Solaris binary support. 2008-04-21 15:10:15 -07:00
mmu_context.h [SPARC64]: dr-cpu unconfigure support. 2007-07-16 04:05:32 -07:00
mmu.h consolidate asm/const.h to linux/const.h 2007-05-08 11:15:13 -07:00
mmzone.h [SPARC64]: Add NUMA support. 2008-04-23 23:32:17 -07:00
module.h
mostek.h [SPARC64]: __inline__ --> inline 2007-10-27 00:13:04 -07:00
msgbuf.h
mutex.h [PATCH] mutex subsystem, add default include/asm-*/mutex.h files 2006-01-09 15:59:19 -08:00
namei.h [SPARC]: Remove SunOS and Solaris binary support. 2008-04-21 15:10:15 -07:00
ns87303.h [SPARC64]: __inline__ --> inline 2007-10-27 00:13:04 -07:00
of_device.h [SPARC]: Merge include/asm-sparc{,64}/of_device.h 2008-02-09 03:58:32 -08:00
of_platform.h [SPARC]: Remove of_platform_device_create 2008-02-09 03:49:58 -08:00
openprom.h [SPARC64]: Bump PROMINTR_MAX to 32. 2007-05-10 00:55:59 -07:00
openpromio.h
oplib.h [SPARC64]: Fix lockdep, particularly on SMP. 2007-09-16 11:51:15 -07:00
page.h hugetlbfs: architecture header cleanup 2008-04-28 08:58:25 -07:00
param.h Don't include linux/config.h from anywhere else in include/ 2006-04-26 12:56:16 +01:00
parport.h [SPARC64]: __inline__ --> inline 2007-10-27 00:13:04 -07:00
pci.h [SPARC64]: Implement pci_resource_to_user() 2007-12-26 19:33:46 -08:00
percpu.h SPARC64: use generic percpu 2008-01-30 23:27:58 +01:00
perfctr.h
pgalloc.h CONFIG_HIGHPTE vs. sub-page page tables. 2008-02-08 09:22:42 -08:00
pgtable.h mm: introduce pte_special pte bit 2008-04-28 08:58:23 -07:00
pil.h sparc64: Kill PIL_RESERVED, unused. 2008-04-28 04:03:06 -07:00
poll.h Consolidate asm/poll.h 2007-05-11 08:29:34 -07:00
posix_types.h asm-*/posix_types.h: scrub __GLIBC__ 2008-02-08 09:22:34 -08:00
processor.h [SPARC64]: Define TASK_SIZE_OF() 2008-03-26 17:32:33 -07:00
prom.h [SPARC]: Merge include/asm-sparc{,64}/prom.h 2008-02-09 03:56:20 -08:00
psrcompat.h sparc: Fix debugger syscall restart interactions. 2008-05-11 02:07:19 -07:00
pstate.h sparc: Fix debugger syscall restart interactions. 2008-05-11 02:07:19 -07:00
ptrace.h sparc: Fix debugger syscall restart interactions. 2008-05-11 02:07:19 -07:00
reboot.h [SPARC64]: Fix sparse warnings wrt. machine_alt_power_off(). 2008-02-19 20:39:18 -08:00
reg.h
resource.h
rtc.h
rwsem-const.h
rwsem.h [SPARC64]: Add irqtrace/stacktrace/lockdep support. 2006-12-10 02:39:09 -08:00
sbus.h [SPARC64]: __inline__ --> inline 2007-10-27 00:13:04 -07:00
scatterlist.h Add CONFIG_DEBUG_SG sg validation 2007-10-22 21:20:03 +02:00
scratchpad.h [SPARC64]: Sun4v scratchpad register layout. 2006-03-20 01:11:44 -08:00
seccomp.h
sections.h
semaphore.h Generic semaphore implementation 2008-04-17 10:42:34 -04:00
sembuf.h
setup.h [SPARC64]: Increase command line size to 2048 like other arches. 2007-02-12 15:15:47 -08:00
sfafsr.h consolidate asm/const.h to linux/const.h 2007-05-08 11:15:13 -07:00
sfp-machine.h [MATH-EMU]: Fix underflow exception reporting. 2007-08-16 22:59:49 -07:00
shmbuf.h
shmparam.h unexport asm/shmparam.h 2007-10-17 08:42:47 -07:00
sigcontext.h
siginfo.h Don't include linux/config.h from anywhere else in include/ 2006-04-26 12:56:16 +01:00
signal.h sparc: Fix debugger syscall restart interactions. 2008-05-11 02:07:19 -07:00
smp.h remove asm/bitops.h includes 2007-10-19 11:53:41 -07:00
socket.h [SPARC]: Remove SunOS and Solaris binary support. 2008-04-21 15:10:15 -07:00
sockios.h [NET]: Introduce SIOCGSTAMPNS ioctl to get timestamps with nanosec resolution 2007-04-25 22:24:04 -07:00
sparsemem.h [SPARC64]: Decrease SECTION_SIZE_BITS to 30. 2008-04-23 23:32:13 -07:00
spinlock_types.h
spinlock.h [PATCH] Directed yield: cpu_relax variants for spinlocks and rw-locks 2006-10-01 00:39:21 -07:00
spitfire.h [SPARC64]: Remove most limitations to kernel image size. 2008-03-21 17:01:38 -07:00
sstate.h [SPARC64]: Report proper system soft state to the hypervisor. 2007-05-29 02:49:29 -07:00
stacktrace.h [SPARC64]: Make save_stack_trace() more efficient. 2008-03-24 20:06:24 -07:00
starfire.h [SPARC64]: Kill starfire_cookie from SBUS/PCI. 2006-06-29 16:37:08 -07:00
stat.h
statfs.h
string.h
sunbpp.h
syscalls.h [SPARC64]: More sparse warning fixes in process.c 2008-02-19 21:25:50 -08:00
system.h sparc: Add kgdb support. 2008-04-29 02:38:50 -07:00
termbits.h [SPARC]: Support for new termios. 2007-10-17 19:38:10 -07:00
termios.h [SPARC]: Remove SunOS and Solaris binary support. 2008-04-21 15:10:15 -07:00
thread_info.h sparc: Remove old style signal frame support. 2008-04-27 02:26:36 -07:00
timer.h [SPARC64]: Fix sparse warnings in arch/sparc64/kernel/time.c 2008-03-26 01:11:55 -07:00
timex.h read_current_timer() cleanups 2008-02-06 10:41:02 -08:00
tlb.h add mm argument to pte/pmd/pud/pgd_free 2008-02-05 09:44:18 -08:00
tlbflush.h remove unused flush_tlb_pgtables 2007-10-19 11:53:34 -07:00
topology.h [SPARC64]: Add NUMA support. 2008-04-23 23:32:17 -07:00
tsb.h [SPARC64]: Fix two bugs wrt. kernel 4MB TSB. 2007-05-29 02:51:38 -07:00
ttable.h sparc: Fix debugger syscall restart interactions. 2008-05-11 02:07:19 -07:00
types.h sparc64: types: use <asm-generic/int-*.h> for the sparc64 architecture 2008-05-02 16:18:41 -07:00
uaccess.h aout: remove unnecessary inclusions of {asm, linux}/a.out.h 2008-02-08 09:22:30 -08:00
uctx.h
unaligned.h kernel: Move arches to use common unaligned access 2008-04-29 08:06:27 -07:00
unistd.h [SPARC]: Remove SunOS and Solaris binary support. 2008-04-21 15:10:15 -07:00
upa.h [SPARC64]: __inline__ --> inline 2007-10-27 00:13:04 -07:00
user.h [SPARC]: Remove SunOS and Solaris binary support. 2008-04-21 15:10:15 -07:00
utrap.h
vga.h [PATCH] vgacon: make VGA_MAP_MEM take size, remove extra use 2006-06-22 15:05:58 -07:00
vio.h [SPARC64]: Use "is_power_of_2" macro for simplicity. 2007-11-07 02:24:33 -08:00
visasm.h [SPARC64]: __inline__ --> inline 2007-10-27 00:13:04 -07:00
watchdog.h
xor.h [SPARC64]: Do not assume sun4v chips have load-twin/store-init support. 2007-08-08 17:33:45 -07:00