Re: [RFC][PATCH 00/17] Fix up the recent SRSO patches

[a-development]

It worked, it worked!

https://up.tail.ws/txt/working-suspend.txt

I've tested it now quite some time.
But, I also had to start using 6.6.26-1-lts because my magewell capture 
card wouldn't without.

Thanks again!

On 26.03.2024 23:21, Borislav Petkov wrote:
> Whoops,
>
> this fell through the cracks. Sorry about that.
>
> On Mon, Jan 29, 2024 at 06:18:00PM +0000, a-development@xxxxxxxxx 
> wrote:
> > I have the feeling that something else is amiss.
> > Currently under 6.7.2-2-cachyos with srso=off.
> > https://0x0.st/HDqP.txt
>
> Yah, your tasks refuse to freeze on suspend and they have this fuse
> stuff in the stacktrace:
>
> [ 6346.492593] task:btop            state:D stack:0     pid:279617
> tgid:1548  ppid:1531   flags:0x00004006
> [ 6346.492600] Call Trace:
> [ 6346.492602]  <TASK>
> [ 6346.492607]  __schedule+0xd44/0x1af0
> [ 6346.492614]  ? srso_alias_return_thunk+0x5/0xfbef5
> [ 6346.492617]  ? __wake_up+0x9d/0xc0
> [ 6346.492622]  schedule+0x32/0xd0
> [ 6346.492627]  request_wait_answer+0xd0/0x2a0 [fuse
> db37c699d94393e946cf93306449ea0f307959a1]
> [ 6346.492638]  ? __pfx_autoremove_wake_function+0x10/0x10
> [ 6346.492643]  fuse_simple_request+0x21c/0x390 [fuse
> db37c699d94393e946cf93306449ea0f307959a1]
> [ 6346.492653]  fuse_statfs+0xf2/0x160 [fuse
> db37c699d94393e946cf93306449ea0f307959a1]
> [ 6346.492667]  statfs_by_dentry+0x67/0x90
>
> > Now I feel, further communication is rather selfish, as a clean 
> > environment
> > is hard to provide.
> > In any case, my FUSE arguments are sshfs -o kernel_cache -o auto_cache 
> > -o
> > reconnect \
> >                -o compression=yes -o cache_timeout=600 -o
> > ServerAliveInterval=30 \
> >                "$source" "$target" -o idmap=user
> >
> > With this line, I somehow managed to have the FUSE mount infinitely 
> > mounted,
> > even if the device was offline for couple of days.
> > A followed suspend would fail to freeze.
> > srso=off would reproducibly work.
>
> Not in your example above. It would fail after a couple of suspend
> cycles.
>
> And looking at your splats
>
> [ 6366.524953]  ? switch_fpu_return+0x50/0xe0
> [ 6366.524956]  ? srso_alias_return_thunk+0x5/0xfbef5
> 		  ^^^^^^^^^^^^^^^^^^^^^^^^
> [ 6366.524958]  ? exit_to_user_mode_prepare+0x132/0x1f
>
> the right cmdline option to disable it is:
>
> spec_rstack_overflow=off
>
> not
>
> srso=off
>
> :-)
>
> > Please provide me a specific version of a kernel I should try in my
> > configuration to try and reproduce.
> > I'd prefer a pre-compiled one; if not tell me...
> > I use archlinux.
>
> Just build the latest released kernel, which is 6.8 now. Take your
> .config and use it to build it. The net is full of tutorials how to do
> so.
>
> And then try with spec_rstack_overflow=off and let's see what that 
> does.
>
> > Please give me a reason to not feel bad about myself.
>
> Don't worry - it's just a machine. :)