Bug reported by Alexander Beregalov.
Before we dereference the stack frame or try to peek at the
pt_regs magic value, make sure the entire object is within
the kernel stack bounds.
Signed-off-by: David S. Miller <davem@davemloft.net>
All of the xcall delivery implementation is cpumask agnostic, so
we can pass around pointers to const cpumask_t objects everywhere.
The sad remaining case is the argument to arch_send_call_function_ipi().
Signed-off-by: David S. Miller <davem@davemloft.net>
It can eat up a lot of stack space when NR_CPUS is large.
We retain some of it's functionality by reporting at least one
of the cpu's which are seen in error state.
Signed-off-by: David S. Miller <davem@davemloft.net>
Then modify all of the xcall dispatch implementations get passed and
use this information.
Now all of the xcall dispatch implementations do not need to be mindful
of details such as "is current cpu in the list?" and "is cpu online?"
Signed-off-by: David S. Miller <davem@davemloft.net>
This just facilitates the next changeset where we'll be building
the cpu list and mondo block in this helper function.
Signed-off-by: David S. Miller <davem@davemloft.net>
Ideally this could be simplified further such that we could pass
the pointer down directly into the xcall_deliver() implementation.
But if we do that we need to do the "cpu_online(cpu)" and
"cpu != self" checks down in those functions.
Signed-off-by: David S. Miller <davem@davemloft.net>
For these cases the callers make sure:
1) The cpus indicated are online.
2) The current cpu is not in the list of indicated cpus.
Therefore we can pass a pointer to the mask directly.
One of the motivations in this transformation is to make use of
"&cpumask_of_cpu(cpu)" which evaluates to a pointer to constant
data in the kernel and thus takes up no stack space.
Hopefully someone in the future will change the interface of
arch_send_call_function_ipi() such that it passes a const cpumask_t
pointer so that this will optimize ever further.
Signed-off-by: David S. Miller <davem@davemloft.net>
Removed duplicated #include <linux/tracehook.h> in
arch/sparc64/kernel/signal.c.
Signed-off-by: Huang Weiyi <weiyi.huang@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
That's the userland thread register, so we should never try to change
it like this.
Based upon glibc bug nptl/6577 and suggestions by Jakub Jelinek.
Signed-off-by: David S. Miller <davem@davemloft.net>
The story is that what we used to do when we actually used
smp_report_regs() is that if you specifically only wanted to have the
current cpu's registers dumped you would call "__show_regs()"
otherwise you would call show_regs() which also invoked
smp_report_regs().
Now that we killed off smp_report_regs() there is no longer any
reason to have these two routines, just show_regs() is sufficient.
Also kill off a stray declaration of show_regs() in sparc64_ksym.c
Signed-off-by: David S. Miller <davem@davemloft.net>
All the call sites are #if 0'd out and we have a much more
useful global cpu dumping facility these days. smp_report_regs()
is way too verbose to be usable.
Signed-off-by: David S. Miller <davem@davemloft.net>
It just clutters everything up and even though I wrote that hack I
can't remember having used it in the last 5 years or so.
Signed-off-by: David S. Miller <davem@davemloft.net>
Record one more level of stack frame program counter.
Particularly when lockdep and all sorts of spinlock debugging is
enabled, figuring out the caller of spin_lock() is difficult when the
cpu is stuck on the lock.
Signed-off-by: David S. Miller <davem@davemloft.net>
Call the standard hook after setting up signal handlers.
Signed-off-by: Roland McGrath <roland@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
