Re: [PATCH] usercopy: Avoid soft lockups in test_check_nonzero_user()

2019-10-16 Thread Christian Brauner
On Wed, Oct 16, 2019 at 11:28:20PM +1100, Michael Ellerman wrote: > Christian Brauner writes: > > On Fri, Oct 11, 2019 at 02:48:10PM +1100, Aleksa Sarai wrote: > >> On 2019-10-11, Michael Ellerman wrote: > >> > On a machine with a 64K PAGE_SIZE, the nested for loops in > >> >

Re: [PATCH] usercopy: Avoid soft lockups in test_check_nonzero_user()

2019-10-16 Thread Michael Ellerman
Christian Brauner writes: > On Fri, Oct 11, 2019 at 02:48:10PM +1100, Aleksa Sarai wrote: >> On 2019-10-11, Michael Ellerman wrote: >> > On a machine with a 64K PAGE_SIZE, the nested for loops in >> > test_check_nonzero_user() can lead to soft lockups, eg: >> > >> > watchdog: BUG: soft lockup

Re: [PATCH] usercopy: Avoid soft lockups in test_check_nonzero_user()

2019-10-12 Thread Aleksa Sarai
On 2019-10-12, Michael Ellerman wrote: > Aleksa Sarai writes: > > On 2019-10-11, Michael Ellerman wrote: > >> On a machine with a 64K PAGE_SIZE, the nested for loops in > >> test_check_nonzero_user() can lead to soft lockups, eg: > ... > >> diff --git a/lib/test_user_copy.c

Re: [PATCH] usercopy: Avoid soft lockups in test_check_nonzero_user()

2019-10-12 Thread Michael Ellerman
Aleksa Sarai writes: > On 2019-10-11, Michael Ellerman wrote: >> On a machine with a 64K PAGE_SIZE, the nested for loops in >> test_check_nonzero_user() can lead to soft lockups, eg: ... >> diff --git a/lib/test_user_copy.c b/lib/test_user_copy.c >> index 950ee88cd6ac..9fb6bc609d4c 100644 >> ---

Re: [PATCH] usercopy: Avoid soft lockups in test_check_nonzero_user()

2019-10-11 Thread Christian Brauner
On Fri, Oct 11, 2019 at 02:48:10PM +1100, Aleksa Sarai wrote: > On 2019-10-11, Michael Ellerman wrote: > > On a machine with a 64K PAGE_SIZE, the nested for loops in > > test_check_nonzero_user() can lead to soft lockups, eg: > > > > watchdog: BUG: soft lockup - CPU#4 stuck for 22s!

Re: [PATCH] usercopy: Avoid soft lockups in test_check_nonzero_user()

2019-10-10 Thread Aleksa Sarai
On 2019-10-11, Michael Ellerman wrote: > On a machine with a 64K PAGE_SIZE, the nested for loops in > test_check_nonzero_user() can lead to soft lockups, eg: > > watchdog: BUG: soft lockup - CPU#4 stuck for 22s! [modprobe:611] > Modules linked in: test_user_copy(+) vmx_crypto gf128mul

[PATCH] usercopy: Avoid soft lockups in test_check_nonzero_user()

2019-10-10 Thread Michael Ellerman
On a machine with a 64K PAGE_SIZE, the nested for loops in test_check_nonzero_user() can lead to soft lockups, eg: watchdog: BUG: soft lockup - CPU#4 stuck for 22s! [modprobe:611] Modules linked in: test_user_copy(+) vmx_crypto gf128mul crc32c_vpmsum virtio_balloon ip_tables x_tables autofs4