On Wed, Oct 28, 2020 at 12:15:07PM +0000, Catalin Marinas wrote: > On Tue, Oct 27, 2020 at 09:51:17PM +0000, Will Deacon wrote: > > diff --git a/Documentation/ABI/testing/sysfs-devices-system-cpu b/Documentation/ABI/testing/sysfs-devices-system-cpu > > index b555df825447..19893fb8e870 100644 > > --- a/Documentation/ABI/testing/sysfs-devices-system-cpu > > +++ b/Documentation/ABI/testing/sysfs-devices-system-cpu > > @@ -472,6 +472,14 @@ Description: AArch64 CPU registers > > 'identification' directory exposes the CPU ID registers for > > identifying model and revision of the CPU. > > > > +What: /sys/devices/system/cpu/aarch32_el0 > > Nitpick: should we call this aarch32_el0_present? It's not exactly > present as we populate it as CPUs come online but it's closer to this > mask than to the online one. I don't think so, because a CPU could be set in this mask but not in the present mask, which is hugely confusing it it has "present" in the name! > > +Date: October 2020 > > +Contact: Linux ARM Kernel Mailing list <linux-arm-kernel@xxxxxxxxxxxxxxxxxxx> > > +Description: Identifies the subset of CPUs in the system that can execute > > + AArch32 (32-bit ARM) applications. If absent, then all or none > > + of the CPUs can execute AArch32 applications and execve() will > > + behave accordingly. > > What does "accordingly" mean? Normally, we'd get ENOEXEC but here the > execve() "succeeds" followed by a SIGKILL if it ends up on the wrong > CPU. No; if the file is absent then execve() behaves as it always has. Will
