Re: [PATCH v5 17/17] powerpc/32s: Enable CONFIG_VMAP_STACK

[Guenter Roeck]

On 2/7/20 5:29 AM, Christophe Leroy wrote:
> On 02/07/2020 01:08 PM, Guenter Roeck wrote:
> > On 2/7/20 12:28 AM, Christophe Leroy wrote:
> > > On 02/07/2020 06:13 AM, Christophe Leroy wrote:
> > > > Le 06/02/2020 Ã 21:31, Guenter Roeck a ÃcritÂ:
> > > > > On Sat, Dec 21, 2019 at 08:32:38AM +0000, Christophe Leroy wrote:
> > > > > > A few changes to retrieve DAR and DSISR from struct regs
> > > > > > instead of retrieving them directly, as they may have
> > > > > > changed due to a TLB miss.
> > > > > >
> > > > > > Also modifies hash_page() and friends to work with virtual
> > > > > > data addresses instead of physical ones. Same on load_up_fpu()
> > > > > > and load_up_altivec().
> > > > > >
> > > > > > Signed-off-by: Christophe Leroy <christophe.leroy@xxxxxx>
> > > > >
> > > > > This patch results in qemu boot failures (mac99 with pmac32_defconfig).
> > > > > Images fail silently; there is no console output. Reverting the patch
> > > > > fixes the problem. Bisect log is attached below.
> > > > >
> > > > > Assuming this was tested on real hardware, am I correct to assume that qemu
> > > > > for ppc32 (more specifically, qemu's mac99 and g3beige machines) no longer
> > > > > works with the upstream kernel ?
> > > >
> > > > Before submitting the series, I successfully tested:
> > > > - Real HW with powerpc 8xx
> > > > - Real HW with powerpc 832x
> > > > - Qemu's mac99
> > > >
> > > > I'll re-check the upstream kernel.
> > >
> > > This is still working for me with the upstream kernel:
> >
> > Interesting. What is your kernel configuration, your qemu version, and
> > your qemu command line ?
>
> Config is pmac32_defconfig + CONFIG_DEVTMPFS (But kernel also boots without CONFIG_DEVTMPFS)
>
> QEMU emulator version 2.11.2
>
> qemu-system-ppc -kernel vmlinux -M mac99 -initrd rootfs.cpio.gz -s -m 1024
>
> Works with both GCC 5.5 and GCC 8.1
Actually, the problem is that I have locking selftest options enabled
in my tests. Everything works if I disable those. The "culprit" seems
to be CONFIG_PROVE_LOCKING. Can you retest with CONFIG_PROVE_LOCKING=y ?

Thanks,
Guenter