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  1. 06 Aug, 2019 4 commits
    • Douglas Anderson's avatar
      ARM: dts: rockchip: Mark that the rk3288 timer might stop in suspend · ea26b427
      Douglas Anderson authored 
      [ Upstream commit 8ef1ba39 ]

This is similar to commit e6186820 ("arm64: dts: rockchip: Arch
counter doesn't tick in system suspend").  Specifically on the rk3288
it can be seen that the timer stops ticking in suspend if we end up
running through the "osc_disable" path in rk3288_slp_mode_set().  In
that path the 24 MHz clock will turn off and the timer stops.

To test this, I ran this on a Chrome OS filesystem:
  before=$(date); \
  suspend_stress_test -c1 --suspend_min=30 --suspend_max=31; \
  echo ${before}; date

...and I found that unless I plug in a device that requests USB wakeup
to be active that the two calls to "date" would show that fewer than
30 seconds passed.

NOTE: deep suspend (where the 24 MHz clock gets disabled) isn't
supported yet on upstream Linux so this was tested on a downstream
kernel.
Signed-off-by: default avatarDouglas Anderson <dianders@chromium.org>
Signed-off-by: default avatarHeiko Stuebner <heiko@sntech.de>
Signed-off-by: default avatarSasha Levin <sashal@kernel.org>
      ea26b427
    • Douglas Anderson's avatar
      ARM: dts: rockchip: Make rk3288-veyron-mickey's emmc work again · 22befe67
      Douglas Anderson authored 
      [ Upstream commit 99fa0667 ]

When I try to boot rk3288-veyron-mickey I totally fail to make the
eMMC work.  Specifically my logs (on Chrome OS 4.19):

  mmc_host mmc1: card is non-removable.
  mmc_host mmc1: Bus speed (slot 0) = 400000Hz (slot req 400000Hz, actual 400000HZ div = 0)
  mmc_host mmc1: Bus speed (slot 0) = 50000000Hz (slot req 52000000Hz, actual 50000000HZ div = 0)
  mmc1: switch to bus width 8 failed
  mmc1: switch to bus width 4 failed
  mmc1: new high speed MMC card at address 0001
  mmcblk1: mmc1:0001 HAG2e 14.7 GiB
  mmcblk1boot0: mmc1:0001 HAG2e partition 1 4.00 MiB
  mmcblk1boot1: mmc1:0001 HAG2e partition 2 4.00 MiB
  mmcblk1rpmb: mmc1:0001 HAG2e partition 3 4.00 MiB, chardev (243:0)
  mmc_host mmc1: Bus speed (slot 0) = 400000Hz (slot req 400000Hz, actual 400000HZ div = 0)
  mmc_host mmc1: Bus speed (slot 0) = 50000000Hz (slot req 52000000Hz, actual 50000000HZ div = 0)
  mmc1: switch to bus width 8 failed
  mmc1: switch to bus width 4 failed
  mmc1: tried to HW reset card, got error -110
  mmcblk1: error -110 requesting status
  mmcblk1: recovery failed!
  print_req_error: I/O error, dev mmcblk1, sector 0
  ...

When I remove the '/delete-property/mmc-hs200-1_8v' then everything is
hunky dory.

That line comes from the original submission of the mickey dts
upstream, so presumably at the time the HS200 was failing and just
enumerating things as a high speed device was fine.  ...or maybe it's
just that some mickey devices work when enumerating at "high speed",
just not mine?

In any case, hs200 seems good now.  Let's turn it on.
Signed-off-by: default avatarDouglas Anderson <dianders@chromium.org>
Signed-off-by: default avatarHeiko Stuebner <heiko@sntech.de>
Signed-off-by: default avatarSasha Levin <sashal@kernel.org>
      22befe67
    • Douglas Anderson's avatar
      ARM: dts: rockchip: Make rk3288-veyron-minnie run at hs200 · 8c5a33d3
      Douglas Anderson authored 
      [ Upstream commit 1c047902 ]

As some point hs200 was failing on rk3288-veyron-minnie.  See commit
98492678 ("ARM: dts: rockchip: temporarily remove emmc hs200 speed
from rk3288 minnie").  Although I didn't track down exactly when it
started working, it seems to work OK now, so let's turn it back on.

To test this, I booted from SD card and then used this script to
stress the enumeration process after fixing a memory leak [1]:
  cd /sys/bus/platform/drivers/dwmmc_rockchip
  for i in $(seq 1 3000); do
    echo "========================" $i
    echo ff0f0000.dwmmc > unbind
    sleep .5
    echo ff0f0000.dwmmc > bind
    while true; do
      if [ -e /dev/mmcblk2 ]; then
        break;
      fi
      sleep .1
    done
  done

It worked fine.

[1] https://lkml.kernel.org/r/20190503233526.226272-1-dianders@chromium.orgSigned-off-by: default avatarDouglas Anderson <dianders@chromium.org>
Signed-off-by: default avatarHeiko Stuebner <heiko@sntech.de>
Signed-off-by: default avatarSasha Levin <sashal@kernel.org>
      8c5a33d3
    • Russell King's avatar
      ARM: riscpc: fix DMA · 3c1d1bad
      Russell King authored 
      [ Upstream commit ffd9a1ba ]

DMA got broken a while back in two different ways:
1) a change in the behaviour of disable_irq() to wait for the interrupt
   to finish executing causes us to deadlock at the end of DMA.
2) a change to avoid modifying the scatterlist left the first transfer
   uninitialised.

DMA is only used with expansion cards, so has gone unnoticed.

Fixes: fa4e9989 ("[ARM] dma: RiscPC: don't modify DMA SG entries")
Signed-off-by: default avatarRussell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: default avatarSasha Levin <sashal@kernel.org>
      3c1d1bad
  3. 04 Aug, 2019 34 commits
  5. 31 Jul, 2019 2 commits
    • Greg Kroah-Hartman's avatar
      Linux 4.19.63 · 9a9de33a
      Greg Kroah-Hartman authored
      9a9de33a
    • Linus Torvalds's avatar
      access: avoid the RCU grace period for the temporary subjective credentials · 408af823
      Linus Torvalds authored 
      commit d7852fbd upstream.

It turns out that 'access()' (and 'faccessat()') can cause a lot of RCU
work because it installs a temporary credential that gets allocated and
freed for each system call.

The allocation and freeing overhead is mostly benign, but because
credentials can be accessed under the RCU read lock, the freeing
involves a RCU grace period.

Which is not a huge deal normally, but if you have a lot of access()
calls, this causes a fair amount of seconday damage: instead of having a
nice alloc/free patterns that hits in hot per-CPU slab caches, you have
all those delayed free's, and on big machines with hundreds of cores,
the RCU overhead can end up being enormous.

But it turns out that all of this is entirely unnecessary.  Exactly
because access() only installs the credential as the thread-local
subjective credential, the temporary cred pointer doesn't actually need
to be RCU free'd at all.  Once we're done using it, we can just free it
synchronously and avoid all the RCU overhead.

So add a 'non_rcu' flag to 'struct cred', which can be set by users that
know they only use it in non-RCU context (there are other potential
users for this).  We can make it a union with the rcu freeing list head
that we need for the RCU case, so this doesn't need any extra storage.

Note that this also makes 'get_current_cred()' clear the new non_rcu
flag, in case we have filesystems that take a long-term reference to the
cred and then expect the RCU delayed freeing afterwards.  It's not
entirely clear that this is required, but it makes for clear semantics:
the subjective cred remains non-RCU as long as you only access it
synchronously using the thread-local accessors, but you _can_ use it as
a generic cred if you want to.

It is possible that we should just remove the whole RCU markings for
->cred entirely.  Only ->real_cred is really supposed to be accessed
through RCU, and the long-term cred copies that nfs uses might want to
explicitly re-enable RCU freeing if required, rather than have
get_current_cred() do it implicitly.

But this is a "minimal semantic changes" change for the immediate
problem.
Acked-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: default avatarEric Dumazet <edumazet@google.com>
Acked-by: default avatarPaul E. McKenney <paulmck@linux.ibm.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Jan Glauber <jglauber@marvell.com>
Cc: Jiri Kosina <jikos@kernel.org>
Cc: Jayachandran Chandrasekharan Nair <jnair@marvell.com>
Cc: Greg KH <greg@kroah.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: David Howells <dhowells@redhat.com>
Cc: Miklos Szeredi <miklos@szeredi.hu>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      408af823
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