Re: [GIT PULL] x86/asm changes for v5.6

[Mike Rapoport]

On Thu, Jan 30, 2020 at 08:55:49AM +0100, Borislav Petkov wrote:
> Hello Damian,
> 
> On Thu, Jan 30, 2020 at 06:47:14AM +0100, Damian Tometzki wrote:
> > in my qemu env the system isnt coming up. I tried both with and without the
> > changes from Borislav.
> 
> in the future, please do not hijack the thread like that but start a new
> one or open a bug on bugzilla.kernel.org. Your issue is something else.
> 
> > 0.605193] ------------[ cut here ]------------
> > [    0.605933] General protection fault in user access. Non-canonical
> > address?
> 
> There it is.
> 
> > [    0.605948] WARNING: CPU: 0 PID: 1 at arch/x86/mm/extable.c:77
> > ex_handler_uaccess+0x48/0x50
> > [    0.606931] Modules linked in:
> > [    0.606931] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.5.0 #15
> > [    0.606931] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
> > rel-1.12.0-0-ga698c8995f-prebuilt.qemu.org 04/01/2014
> > [    0.606931] RIP: 0010:ex_handler_uaccess+0x48/0x50

...
 
> It looks like dquot_init->register_sysctl_table-> ... does copy_to_user
> at some point and it goes off into the weeds and %rsi becomes
> non-canonical.
> 
> Please start a new thread or open a bug and upload your .config and
> dmesg. We'll continue debugging that there.

Maybe that won't be needed.

It seems that this a random boot crash caused by 987f028b8637cfa7 ("char:
hpet: Use flexible-array member") and fix is on the way:

https://lore.kernel.org/lkml/202001300450.00U4ocvS083098@xxxxxxxxxxxxxxxxxxx/
 
> Thx.
> 
> -- 
> Regards/Gruss,
>     Boris.
> 
> SUSE Software Solutions Germany GmbH, GF: Felix Imendörffer, HRB 36809, AG Nürnberg

-- 
Sincerely yours,
Mike.