Re: [PATCH 2/2] alpha/ptrace: Add missing switch_stack frames

From: Al Viro
Date: Wed Jun 16 2021 - 16:54:12 EST


On Wed, Jun 16, 2021 at 03:49:44PM -0500, Eric W. Biederman wrote:

> Someone might want or try to read them in the case of exit. Which
> without some change will result in a read of other kernel stack content
> on alpha.

And someone might want a pony. Again, why bother restoring those,
_especially_ in case of exit(2)?

> Plus there are coredumps which definitely want to read everything.

Huh? In case of coredump we are going to have come through
$work_notifysig:
mov $sp, $16
DO_SWITCH_STACK
jsr $26, do_work_pending
so they *do* have full pt_regs saved. What's the problem?