[PARISC] Add ability for prctl to change unaligned trap behaviour
Add support for changing unaligned trap behaviour on a
per-thread basis.
Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
diff --git a/arch/parisc/kernel/unaligned.c b/arch/parisc/kernel/unaligned.c
index 62eea35..eaae8a0 100644
--- a/arch/parisc/kernel/unaligned.c
+++ b/arch/parisc/kernel/unaligned.c
@@ -513,15 +513,18 @@
register int flop=0; /* true if this is a flop */
/* log a message with pacing */
- if (user_mode(regs))
- {
- if (unaligned_count > 5 && jiffies - last_time > 5*HZ)
- {
+ if (user_mode(regs)) {
+ if (current->thread.flags & PARISC_UAC_SIGBUS) {
+ goto force_sigbus;
+ }
+
+ if (unaligned_count > 5 && jiffies - last_time > 5*HZ) {
unaligned_count = 0;
last_time = jiffies;
}
- if (++unaligned_count < 5)
- {
+
+ if (!(current->thread.flags & PARISC_UAC_NOPRINT)
+ && ++unaligned_count < 5) {
char buf[256];
sprintf(buf, "%s(%d): unaligned access to 0x" RFMT " at ip=0x" RFMT "\n",
current->comm, current->pid, regs->ior, regs->iaoq[0]);
@@ -530,6 +533,7 @@
show_regs(regs);
#endif
}
+
if (!unaligned_enabled)
goto force_sigbus;
}
diff --git a/include/asm-parisc/processor.h b/include/asm-parisc/processor.h
index a9dfadd..aae40e8 100644
--- a/include/asm-parisc/processor.h
+++ b/include/asm-parisc/processor.h
@@ -122,8 +122,27 @@
};
/* Thread struct flags. */
+#define PARISC_UAC_NOPRINT (1UL << 0) /* see prctl and unaligned.c */
+#define PARISC_UAC_SIGBUS (1UL << 1)
#define PARISC_KERNEL_DEATH (1UL << 31) /* see die_if_kernel()... */
+#define PARISC_UAC_SHIFT 0
+#define PARISC_UAC_MASK (PARISC_UAC_NOPRINT|PARISC_UAC_SIGBUS)
+
+#define SET_UNALIGN_CTL(task,value) \
+ ({ \
+ (task)->thread.flags = (((task)->thread.flags & ~PARISC_UAC_MASK) \
+ | (((value) << PARISC_UAC_SHIFT) & \
+ PARISC_UAC_MASK)); \
+ 0; \
+ })
+
+#define GET_UNALIGN_CTL(task,addr) \
+ ({ \
+ put_user(((task)->thread.flags & PARISC_UAC_MASK) \
+ >> PARISC_UAC_SHIFT, (int __user *) (addr)); \
+ })
+
#define INIT_THREAD { \
regs: { gr: { 0, }, \
fr: { 0, }, \