On Wed, Aug 16, 2023 at 12:13 PM Huang, Kai <kai.huang@xxxxxxxxx> wrote:
>
> On Tue, 2023-08-15 at 20:22 +0200, Jack Wang wrote:
> > We hit softlocup with following call trace:
>
> Please add an empty line for better readability.
>
> > ? asm_sysvec_apic_timer_interrupt+0x16/0x20
> > xa_erase+0x21/0xb0
> > ? sgx_free_epc_page+0x20/0x50
> > sgx_vepc_release+0x75/0x220
> > __fput+0x89/0x250
> > task_work_run+0x59/0x90
> > do_exit+0x337/0x9a0
> >
> > Similar like commit
> > 8795359e35bc ("x86/sgx: Silence softlockup detection when releasing large enclaves")
>
> Please wrap text properly.
>
> > The test system has 64GB of enclave memory, and all assigned to a single
> > VM. Release vepc take longer time and triggers the softlockup warning.
> >
> > Add a cond_resched() to give other tasks a chance to run and placate
> ^
>
> You are adding more than one 'cond_resched()', so remove 'a'.
>
> > the softlockup detector.
Hi Kai,
Thx for the comments, sorry for slow reply. was busy with other high
prio tasks. I've answered your initial input in v1 patch.
I will wait a bit see if there is other comments, maybe the maintainer
want to fix them while apply
Thx!
> >
> > Cc: Jarkko Sakkinen <jarkko@xxxxxxxxxx>
> > Cc: Haitao Huang <haitao.huang@xxxxxxxxxxxxxxx>
> > Cc: stable@xxxxxxxxxxxxxxx
> > Fixes: 540745ddbc70 ("x86/sgx: Introduce virtual EPC for use by KVM guests")
> > Reported-by: Yu Zhang <yu.zhang@xxxxxxxxx>
> > Tested-by: Yu Zhang <yu.zhang@xxxxxxxxx>
> > Acked-by: Haitao Huang <haitao.huang@xxxxxxxxxxxxxxx>
> > Reviewed-by: Jarkko Sakkinen <jarkko@xxxxxxxxxx>
> > Signed-off-by: Jack Wang <jinpu.wang@xxxxxxxxx>
> > ---
> > v2:
> > * collects review and test by.
> > * add fixes tag
> > * trim call trace.
> >
> > arch/x86/kernel/cpu/sgx/virt.c | 2 ++
> > 1 file changed, 2 insertions(+)
> >
> > diff --git a/arch/x86/kernel/cpu/sgx/virt.c b/arch/x86/kernel/cpu/sgx/virt.c
> > index c3e37eaec8ec..01d2795792cc 100644
> > --- a/arch/x86/kernel/cpu/sgx/virt.c
> > +++ b/arch/x86/kernel/cpu/sgx/virt.c
> > @@ -204,6 +204,7 @@ static int sgx_vepc_release(struct inode *inode, struct file *file)
> > continue;
> >
> > xa_erase(&vepc->page_array, index);
> > + cond_resched();
> > }
> >
> > /*
> > @@ -222,6 +223,7 @@ static int sgx_vepc_release(struct inode *inode, struct file *file)
> > list_add_tail(&epc_page->list, &secs_pages);
> >
> > xa_erase(&vepc->page_array, index);
> > + cond_resched();
> > }
> >
> >
>
> Comments ignored without explanation:
>
> https://lore.kernel.org/linux-sgx/op.19p011pawjvjmi@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx/T/#mf004deb81f9eb1eab7ad3c1c88746bfa23d5109c
>
