diff options
Diffstat (limited to 'arch/powerpc/kernel/traps.c')
| -rw-r--r-- | arch/powerpc/kernel/traps.c | 29 |
1 files changed, 29 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/traps.c b/arch/powerpc/kernel/traps.c index 487e1b442473..2f5ef5a80353 100644 --- a/arch/powerpc/kernel/traps.c +++ b/arch/powerpc/kernel/traps.c @@ -1390,6 +1390,13 @@ void vsx_unavailable_exception(struct pt_regs *regs) } #ifdef CONFIG_PPC64 +static void tm_unavailable(struct pt_regs *regs) +{ + pr_emerg("Unrecoverable TM Unavailable Exception " + "%lx at %lx\n", regs->trap, regs->nip); + die("Unrecoverable TM Unavailable Exception", regs, SIGABRT); +} + void facility_unavailable_exception(struct pt_regs *regs) { static char *facility_strings[] = { @@ -1469,6 +1476,27 @@ void facility_unavailable_exception(struct pt_regs *regs) return; } + if (status == FSCR_TM_LG) { + /* + * If we're here then the hardware is TM aware because it + * generated an exception with FSRM_TM set. + * + * If cpu_has_feature(CPU_FTR_TM) is false, then either firmware + * told us not to do TM, or the kernel is not built with TM + * support. + * + * If both of those things are true, then userspace can spam the + * console by triggering the printk() below just by continually + * doing tbegin (or any TM instruction). So in that case just + * send the process a SIGILL immediately. + */ + if (!cpu_has_feature(CPU_FTR_TM)) + goto out; + + tm_unavailable(regs); + return; + } + if ((status < ARRAY_SIZE(facility_strings)) && facility_strings[status]) facility = facility_strings[status]; @@ -1481,6 +1509,7 @@ void facility_unavailable_exception(struct pt_regs *regs) "%sFacility '%s' unavailable, exception at 0x%lx, MSR=%lx\n", hv ? "Hypervisor " : "", facility, regs->nip, regs->msr); +out: if (user_mode(regs)) { _exception(SIGILL, regs, ILL_ILLOPC, regs->nip); return; |