/*
* Ptrace test for TAR, PPR, DSCR registers
*
* Copyright (C) 2015 Anshuman Khandual, IBM Corporation.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*/
#include "ptrace.h"
#include "ptrace-tar.h"
/* Tracer and Tracee Shared Data */
int shm_id;
int *cptr;
int *pptr;
void tar(void)
{
unsigned long reg[3];
int ret;
cptr = (int *)shmat(shm_id, NULL, 0);
printf("%-30s TAR: %u PPR: %lx DSCR: %u\n",
user_write, TAR_1, PPR_1, DSCR_1);
mtspr(SPRN_TAR, TAR_1);
mtspr(SPRN_PPR, PPR_1);
mtspr(SPRN_DSCR, DSCR_1);
cptr[2] = 1;
/* Wait on parent */
while (!cptr[0])
asm volatile("" : : : "memory");
reg[0] = mfspr(SPRN_TAR);
reg[1] = mfspr(SPRN_PPR);
reg[2] = mfspr(SPRN_DSCR);
printf("%-30s TAR: %lu PPR: %lx DSCR: %lu\n",
user_read, reg[0], reg[1], reg[2]);
/* Unblock the parent now */
cptr[1] = 1;
shmdt((int *)cptr);
ret = validate_tar_registers(reg, TAR_2, PPR_2, DSCR_2);
if (ret)
exit(1);
exit(0);
}
int trace_tar(pid_t child)
{
unsigned long reg[3];
FAIL_IF(start_trace(child));
FAIL_IF(show_tar_registers(child, reg));
printf("%-30s TAR: %lu PPR: %lx DSCR: %lu\n",
ptrace_read_running, reg[0], reg[1], reg[2]);
FAIL_IF(validate_tar_registers(reg, TAR_1, PPR_1, DSCR_1));
FAIL_IF(stop_trace(child));
return TEST_PASS;
}
int trace_tar_write(pid_t child)
{
FAIL_IF(start_trace(child));
FAIL_IF(write_tar_registers(child, TAR_2, PPR_2, DSCR_2));
printf("%-30s TAR: %u PPR: %lx DSCR: %u\n",
ptrace_write_running, TAR_2, PPR_2, DSCR_2);
FAIL_IF(stop_trace(child));
return TEST_PASS;
}
int ptrace_tar(void)
{
pid_t pid;
int ret, status;
shm_id = shmget(IPC_PRIVATE, sizeof(int) * 3, 0777|IPC_CREAT);
pid = fork();
if (pid < 0) {
perror("fork() failed");
return TEST_FAIL;
}
if (pid == 0)
tar();
if (pid) {
pptr = (int *)shmat(shm_id, NULL, 0);
pptr[0] = 0;
pptr[1] = 0;
while (!pptr[2])
asm volatile("" : : : "memory");
ret = trace_tar(pid);
if (ret)
return ret;
ret = trace_tar_write(pid);
if (ret)
return ret;
/* Unblock the child now */
pptr[0] = 1;
/* Wait on child */
while (!pptr[1])
asm volatile("" : : : "memory");
shmdt((int *)pptr);
ret = wait(&status);
shmctl(shm_id, IPC_RMID, NULL);
if (ret != pid) {
printf("Child's exit status not captured\n");
return TEST_PASS;
}
return (WIFEXITED(status) && WEXITSTATUS(status)) ? TEST_FAIL :
TEST_PASS;
}
return TEST_PASS;
}
int main(int argc, char *argv[])
{
return test_harness(ptrace_tar, "ptrace_tar");
}
mit/?id=08d85f3ea99f1eeafc4e8507936190e86a16ee8c'>root/sound/soc/codecs/wm8770.c
irqdomain: Avoid activating interrupts more than once
Since commit f3b0946d629c ("genirq/msi: Make sure PCI MSIs are
activated early"), we can end-up activating a PCI/MSI twice (once
at allocation time, and once at startup time).
This is normally of no consequences, except that there is some
HW out there that may misbehave if activate is used more than once
(the GICv3 ITS, for example, uses the activate callback
to issue the MAPVI command, and the architecture spec says that
"If there is an existing mapping for the EventID-DeviceID
combination, behavior is UNPREDICTABLE").
While this could be worked around in each individual driver, it may
make more sense to tackle the issue at the core level. In order to
avoid getting in that situation, let's have a per-interrupt flag
to remember if we have already activated that interrupt or not.
Fixes: f3b0946d629c ("genirq/msi: Make sure PCI MSIs are activated early")
Reported-and-tested-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/1484668848-24361-1-git-send-email-marc.zyngier@arm.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>