Re: [PATCH 08/10] parisc: fix livelock in uaccess

Al Viro
2023-03-02T17:53:06Z

On Wed, Mar 01, 2023 at 05:00:11AM +0100, Helge Deller wrote:
> On 2/28/23 23:57, Al Viro wrote:
> > On Tue, Feb 28, 2023 at 09:22:31PM +0100, Helge Deller wrote:
> >
> > > Now I can confirm (with the adjusted reproducer), that your patch
> > > allows to kill the process with SIGKILL, while without your patch
> > > it's not possibe to kill the process at all.
> > > I've tested with a 32- and 64-bit parisc kernel.
> > >
> > > You may add
> > > Tested-by: Helge Deller <deller@gmx.de> # parisc
> > > to the patch.
> > >
> > > If you want me to take the patch (with the warning regarding missing msg variable fixed)
> > > through the parisc tree, please let me know.
> >
> > What message do you prefer there? It matters only for the case when
> > we are hitting an oops there, but...
>
> I have no preference on that message. Maybe "Page fault: fault signal on kernel memory"
> is too generic, so I'm fine with any better idea/wording you come up with.

Ended up going with that... Series reordered and pushed out in #fixes.
Status:
m68k, riscv, hexagon, parisc: tested by arch maintainers
alpha, sparc: locally tested (both sparc32 and sparc64 parts)
ia64, microblaze, nios2, openrisc: builds, but I have no way to test the
resulting kernels (itanic box appears to be pining for fjords and I've no emulator
setup for that, the other three I don't even have userland to test with).