Messages in this thread | | | Subject | Re: Suspend/Resume Broken on AM43/AM33 Platforms | From | Keerthy <> | Date | Mon, 19 Aug 2019 12:57:13 +0530 |
| |
On 19/08/19 11:57 AM, Stephen Boyd wrote: > Quoting Keerthy (2019-08-18 21:24:58) >> Hi Stephen, >> >> commit 03a3bb7ae63150230c5de645dc95e673ebf17e1a >> Author: Stephen Boyd <swboyd@chromium.org> >> Date: Mon Aug 5 16:32:41 2019 -0700 >> >> hwrng: core - Freeze khwrng thread during suspend >> >> Commit seems to be breaking suspend/resume on TI AM43/AM33 platforms. >> >> >> rtcwake: wakeup from "mem" using /dev/rtc0 at Sun Nov 18 02:12:12 2018 >> [ 54.033833] PM: suspend entry (deep) >> [ 54.037741] Filesystems sync: 0.000 seconds >> [ 54.062730] Freezing user space processes ... (elapsed 0.001 seconds) >> done. >> [ 54.071313] OOM killer disabled. >> [ 54.074572] Freezing remaining freezable tasks ... >> [ 74.083121] Freezing of tasks failed after 20.003 seconds (1 tasks >> refusing to freeze, wq_busy=0): >> [ 74.092257] hwrng R running task 0 289 2 >> 0x00000020 >> [ 74.099511] [<c08c64c4>] (__schedule) from [<c08c6a10>] >> (schedule+0x3c/0xc0) >> [ 74.106720] [<c08c6a10>] (schedule) from [<c05dbd8c>] >> (add_hwgenerator_randomness+0xb0/0x100) >> [ 74.115358] [<c05dbd8c>] (add_hwgenerator_randomness) from >> [<bf1803c8>] (hwrng_fillfn+0xc0/0x14c [rng_core]) > > Thanks for the report. I suspect we need to check for freezer in > add_hwgenerator_randomness(). I find it odd that there's another caller > of add_hwgenerator_randomness(), but maybe the ath9k driver can be > converted to some sort of hwrng driver instead of calling into the > kthread directly. > > Anyway, can you try this patch?
I applied the below patch on top of latest next branch.
Fixes the issue.
Thanks, Keerthy
> > ---8<--- > diff --git a/drivers/char/random.c b/drivers/char/random.c > index 5d5ea4ce1442..e2e85ca16410 100644 > --- a/drivers/char/random.c > +++ b/drivers/char/random.c > @@ -2429,6 +2429,7 @@ void add_hwgenerator_randomness(const char *buffer, size_t count, > size_t entropy) > { > struct entropy_store *poolp = &input_pool; > + bool frozen = false; > > if (unlikely(crng_init == 0)) { > crng_fast_load(buffer, count); > @@ -2439,9 +2440,12 @@ void add_hwgenerator_randomness(const char *buffer, size_t count, > * We'll be woken up again once below random_write_wakeup_thresh, > * or when the calling thread is about to terminate. > */ > - wait_event_interruptible(random_write_wait, kthread_should_stop() || > + wait_event_interruptible(random_write_wait, > + kthread_freezable_should_stop(&frozen) || > ENTROPY_BITS(&input_pool) <= random_write_wakeup_bits); > - mix_pool_bytes(poolp, buffer, count); > - credit_entropy_bits(poolp, entropy); > + if (!frozen) { > + mix_pool_bytes(poolp, buffer, count); > + credit_entropy_bits(poolp, entropy); > + } > } > EXPORT_SYMBOL_GPL(add_hwgenerator_randomness); >
| |