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author | Grant Likely <grant.likely@secretlab.ca> | 2010-05-22 08:36:56 +0200 |
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committer | Grant Likely <grant.likely@secretlab.ca> | 2010-05-22 08:36:56 +0200 |
commit | cf9b59e9d3e008591d1f54830f570982bb307a0d (patch) | |
tree | 113478ce8fd8c832ba726ffdf59b82cb46356476 /kernel/signal.c | |
parent | of: change of_match_device to work with struct device (diff) | |
parent | fbmem: avoid printk format warning with 32-bit resources (diff) | |
download | linux-cf9b59e9d3e008591d1f54830f570982bb307a0d.tar.xz linux-cf9b59e9d3e008591d1f54830f570982bb307a0d.zip |
Merge remote branch 'origin' into secretlab/next-devicetree
Merging in current state of Linus' tree to deal with merge conflicts and
build failures in vio.c after merge.
Conflicts:
drivers/i2c/busses/i2c-cpm.c
drivers/i2c/busses/i2c-mpc.c
drivers/net/gianfar.c
Also fixed up one line in arch/powerpc/kernel/vio.c to use the
correct node pointer.
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Diffstat (limited to 'kernel/signal.c')
-rw-r--r-- | kernel/signal.c | 40 |
1 files changed, 40 insertions, 0 deletions
diff --git a/kernel/signal.c b/kernel/signal.c index dbd7fe073c55..825a3f24ad76 100644 --- a/kernel/signal.c +++ b/kernel/signal.c @@ -2735,3 +2735,43 @@ void __init signals_init(void) { sigqueue_cachep = KMEM_CACHE(sigqueue, SLAB_PANIC); } + +#ifdef CONFIG_KGDB_KDB +#include <linux/kdb.h> +/* + * kdb_send_sig_info - Allows kdb to send signals without exposing + * signal internals. This function checks if the required locks are + * available before calling the main signal code, to avoid kdb + * deadlocks. + */ +void +kdb_send_sig_info(struct task_struct *t, struct siginfo *info) +{ + static struct task_struct *kdb_prev_t; + int sig, new_t; + if (!spin_trylock(&t->sighand->siglock)) { + kdb_printf("Can't do kill command now.\n" + "The sigmask lock is held somewhere else in " + "kernel, try again later\n"); + return; + } + spin_unlock(&t->sighand->siglock); + new_t = kdb_prev_t != t; + kdb_prev_t = t; + if (t->state != TASK_RUNNING && new_t) { + kdb_printf("Process is not RUNNING, sending a signal from " + "kdb risks deadlock\n" + "on the run queue locks. " + "The signal has _not_ been sent.\n" + "Reissue the kill command if you want to risk " + "the deadlock.\n"); + return; + } + sig = info->si_signo; + if (send_sig_info(sig, info, t)) + kdb_printf("Fail to deliver Signal %d to process %d.\n", + sig, t->pid); + else + kdb_printf("Signal %d is sent to process %d.\n", sig, t->pid); +} +#endif /* CONFIG_KGDB_KDB */ |