Skip to content

L
linux
Switch branch/tag
  1. 29 Jan, 2015 19 commits
    • Oleg Nesterov's avatar
      exit: pidns: alloc_pid() leaks pid_namespace if child_reaper is exiting · e38a2da7
      Oleg Nesterov authored 
      commit 24c037eb upstream.

alloc_pid() does get_pid_ns() beforehand but forgets to put_pid_ns() if it
fails because disable_pid_allocation() was called by the exiting
child_reaper.

We could simply move get_pid_ns() down to successful return, but this fix
tries to be as trivial as possible.
Signed-off-by: default avatarOleg Nesterov <oleg@redhat.com>
Reviewed-by: default avatar"Eric W. Biederman" <ebiederm@xmission.com>
Cc: Aaron Tomlin <atomlin@redhat.com>
Cc: Pavel Emelyanov <xemul@parallels.com>
Cc: Serge Hallyn <serge.hallyn@ubuntu.com>
Cc: Sterling Alexander <stalexan@redhat.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      e38a2da7
    • Johan Hovold's avatar
      rtc: omap: fix missing wakealarm attribute · e7e31c18
      Johan Hovold authored 
      commit 7ecd9a3f upstream.

The platform device must be registered as wakeup capable before
registering the class device, or the wakealarm attribute will not be
created.

Also make sure to unregister the wakeup source on probe errors.

Fixes: 1d2e2b65 ("rtc: omap: restore back (hard-code) wakeup support")
Signed-off-by: default avatarJohan Hovold <johan@kernel.org>
Reviewed-by: default avatarFelipe Balbi <balbi@ti.com>
Tested-by: default avatarFelipe Balbi <balbi@ti.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Tony Lindgren <tony@atomide.com>
Cc: Benot Cousson <bcousson@baylibre.com>
Cc: Lokesh Vutla <lokeshvutla@ti.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: Sekhar Nori <nsekhar@ti.com>
Cc: Tero Kristo <t-kristo@ti.com>
Cc: Keerthy J <j-keerthy@ti.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      e7e31c18
    • Guo Zeng's avatar
      drivers/rtc/rtc-sirfsoc.c: move hardware initilization earlier in probe · 6354bc71
      Guo Zeng authored 
      commit 0e953255 upstream.

Move rtc register to be later than hardware initialization.  The reason
is that devm_rtc_device_register() will do read_time() which is a
callback accessing hardware.  This sometimes causes a hang in the
hardware related callback.
Signed-off-by: default avatarGuo Zeng <guo.zeng@csr.com>
Signed-off-by: default avatarBarry Song <Baohua.Song@csr.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      6354bc71
    • Jan Kara's avatar
      ncpfs: return proper error from NCP_IOC_SETROOT ioctl · f121bf33
      Jan Kara authored 
      commit a682e9c2 upstream.

If some error happens in NCP_IOC_SETROOT ioctl, the appropriate error
return value is then (in most cases) just overwritten before we return.
This can result in reporting success to userspace although error happened.

This bug was introduced by commit 2e54eb96 ("BKL: Remove BKL from
ncpfs").  Propagate the errors correctly.

Coverity id: 1226925.

Fixes: 2e54eb96 ("BKL: Remove BKL from ncpfs")
Signed-off-by: default avatarJan Kara <jack@suse.cz>
Cc: Petr Vandrovec <petr@vandrovec.name>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      f121bf33
    • Filipe Manana's avatar
      Btrfs: fix fs corruption on transaction abort if device supports discard · 99c4dfd0
      Filipe Manana authored 
      commit 678886bd upstream.

When we abort a transaction we iterate over all the ranges marked as dirty
in fs_info->freed_extents[0] and fs_info->freed_extents[1], clear them
from those trees, add them back (unpin) to the free space caches and, if
the fs was mounted with "-o discard", perform a discard on those regions.
Also, after adding the regions to the free space caches, a fitrim ioctl call
can see those ranges in a block group's free space cache and perform a discard
on the ranges, so the same issue can happen without "-o discard" as well.

This causes corruption, affecting one or multiple btree nodes (in the worst
case leaving the fs unmountable) because some of those ranges (the ones in
the fs_info->pinned_extents tree) correspond to btree nodes/leafs that are
referred by the last committed super block - breaking the rule that anything
that was committed by a transaction is untouched until the next transaction
commits successfully.

I ran into this while running in a loop (for several hours) the fstest that
I recently submitted:

  [PATCH] fstests: add btrfs test to stress chunk allocation/removal and fstrim

The corruption always happened when a transaction aborted and then fsck complained
like this:

   _check_btrfs_filesystem: filesystem on /dev/sdc is inconsistent
   *** fsck.btrfs output ***
   Check tree block failed, want=94945280, have=0
   Check tree block failed, want=94945280, have=0
   Check tree block failed, want=94945280, have=0
   Check tree block failed, want=94945280, have=0
   Check tree block failed, want=94945280, have=0
   read block failed check_tree_block
   Couldn't open file system

In this case 94945280 corresponded to the root of a tree.
Using frace what I observed was the following sequence of steps happened:

   1) transaction N started, fs_info->pinned_extents pointed to
      fs_info->freed_extents[0];

   2) node/eb 94945280 is created;

   3) eb is persisted to disk;

   4) transaction N commit starts, fs_info->pinned_extents now points to
      fs_info->freed_extents[1], and transaction N completes;

   5) transaction N + 1 starts;

   6) eb is COWed, and btrfs_free_tree_block() called for this eb;

   7) eb range (94945280 to 94945280 + 16Kb) is added to
      fs_info->pinned_extents (fs_info->freed_extents[1]);

   8) Something goes wrong in transaction N + 1, like hitting ENOSPC
      for example, and the transaction is aborted, turning the fs into
      readonly mode. The stack trace I got for example:

      [112065.253935]  [<ffffffff8140c7b6>] dump_stack+0x4d/0x66
      [112065.254271]  [<ffffffff81042984>] warn_slowpath_common+0x7f/0x98
      [112065.254567]  [<ffffffffa0325990>] ? __btrfs_abort_transaction+0x50/0x10b [btrfs]
      [112065.261674]  [<ffffffff810429e5>] warn_slowpath_fmt+0x48/0x50
      [112065.261922]  [<ffffffffa032949e>] ? btrfs_free_path+0x26/0x29 [btrfs]
      [112065.262211]  [<ffffffffa0325990>] __btrfs_abort_transaction+0x50/0x10b [btrfs]
      [112065.262545]  [<ffffffffa036b1d6>] btrfs_remove_chunk+0x537/0x58b [btrfs]
      [112065.262771]  [<ffffffffa033840f>] btrfs_delete_unused_bgs+0x1de/0x21b [btrfs]
      [112065.263105]  [<ffffffffa0343106>] cleaner_kthread+0x100/0x12f [btrfs]
      (...)
      [112065.264493] ---[ end trace dd7903a975a31a08 ]---
      [112065.264673] BTRFS: error (device sdc) in btrfs_remove_chunk:2625: errno=-28 No space left
      [112065.264997] BTRFS info (device sdc): forced readonly

   9) The clear kthread sees that the BTRFS_FS_STATE_ERROR bit is set in
      fs_info->fs_state and calls btrfs_cleanup_transaction(), which in
      turn calls btrfs_destroy_pinned_extent();

   10) Then btrfs_destroy_pinned_extent() iterates over all the ranges
       marked as dirty in fs_info->freed_extents[], and for each one
       it calls discard, if the fs was mounted with "-o discard", and
       adds the range to the free space cache of the respective block
       group;

   11) btrfs_trim_block_group(), invoked from the fitrim ioctl code path,
       sees the free space entries and performs a discard;

   12) After an umount and mount (or fsck), our eb's location on disk was full
       of zeroes, and it should have been untouched, because it was marked as
       dirty in the fs_info->pinned_extents tree, and therefore used by the
       trees that the last committed superblock points to.

Fix this by not performing a discard and not adding the ranges to the free space
caches - it's useless from this point since the fs is now in readonly mode and
we won't write free space caches to disk anymore (otherwise we would leak space)
nor any new superblock. By not adding the ranges to the free space caches, it
prevents other code paths from allocating that space and write to it as well,
therefore being safer and simpler.

This isn't a new problem, as it's been present since 2011 (git commit
acce952b).
Signed-off-by: default avatarFilipe Manana <fdmanana@suse.com>
Signed-off-by: default avatarChris Mason <clm@fb.com>
Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      99c4dfd0
    • Takashi Iwai's avatar
      ALSA: hda - Add EAPD fixup for ASUS Z99He laptop · cde6b3a1
      Takashi Iwai authored 
      commit f62f5eff upstream.

The same fixup to enable EAPD is needed for ASUS Z99He with AD1986A
codec like another ASUS machine.
Reported-and-tested-by: default avatarDmitry V. Zimin <pfzim@mail.ru>
Signed-off-by: default avatarTakashi Iwai <tiwai@suse.de>
Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      cde6b3a1
    • Andy Lutomirski's avatar
      x86, kvm: Clear paravirt_enabled on KVM guests for espfix32's benefit · 25861a6a
      Andy Lutomirski authored 
      commit 29fa6825 upstream.

paravirt_enabled has the following effects:

 - Disables the F00F bug workaround warning.  There is no F00F bug
   workaround any more because Linux's standard IDT handling already
   works around the F00F bug, but the warning still exists.  This
   is only cosmetic, and, in any event, there is no such thing as
   KVM on a CPU with the F00F bug.

 - Disables 32-bit APM BIOS detection.  On a KVM paravirt system,
   there should be no APM BIOS anyway.

 - Disables tboot.  I think that the tboot code should check the
   CPUID hypervisor bit directly if it matters.

 - paravirt_enabled disables espfix32.  espfix32 should *not* be
   disabled under KVM paravirt.

The last point is the purpose of this patch.  It fixes a leak of the
high 16 bits of the kernel stack address on 32-bit KVM paravirt
guests.  Fixes CVE-2014-8134.
Suggested-by: default avatarKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: default avatarAndy Lutomirski <luto@amacapital.net>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      25861a6a
    • Daniel Vetter's avatar
      drm/i915: Don't complain about stolen conflicts on gen3 · fe7ef2aa
      Daniel Vetter authored 
      commit 0b6d24c0 upstream.

Apparently stuff works that way on those machines.

I agree with Chris' concern that this is a bit risky but imo worth a
shot in -next just for fun. Afaics all these machines have the pci
resources allocated like that by the BIOS, so I suspect that it's all
ok.

This regression goes back to

commit eaba1b8f
Author: Chris Wilson <chris@chris-wilson.co.uk>
Date:   Thu Jul 4 12:28:35 2013 +0100

    drm/i915: Verify that our stolen memory doesn't conflict

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=76983
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=71031Tested-by: default avatarlu hua <huax.lu@intel.com>
Signed-off-by: default avatarDaniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: default avatarJesse Barnes <jbarnes@virtuousgeek.org>
Tested-by: default avatarPaul Menzel <paulepanter@users.sourceforge.net>
Signed-off-by: default avatarJani Nikula <jani.nikula@intel.com>
Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      fe7ef2aa
    • Eric W. Biederman's avatar
      userns: Rename id_map_mutex to userns_state_mutex · a6ef1147
      Eric W. Biederman authored 
      commit f0d62aec upstream.

Generalize id_map_mutex so it can be used for more state of a user namespace.
Reviewed-by: default avatarAndy Lutomirski <luto@amacapital.net>
Signed-off-by: default avatar"Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      a6ef1147
    • Benjamin Coddington's avatar
      nfsd4: fix xdr4 inclusion of escaped char · 678dff4d
      Benjamin Coddington authored 
      commit 5a64e569 upstream.

Fix a bug where nfsd4_encode_components_esc() includes the esc_end char as
an additional string encoding.
Signed-off-by: default avatarBenjamin Coddington <bcodding@redhat.com>
Fixes: e7a0444a "nfsd: add IPv6 addr escaping to fs_location hosts"
Signed-off-by: default avatarJ. Bruce Fields <bfields@redhat.com>
Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      678dff4d
    • Rasmus Villemoes's avatar
      fs: nfsd: Fix signedness bug in compare_blob · b67dd5ae
      Rasmus Villemoes authored 
      commit ef17af2a upstream.

Bugs similar to the one in acbbe6fb (kcmp: fix standard comparison
bug) are in rich supply.

In this variant, the problem is that struct xdr_netobj::len has type
unsigned int, so the expression o1->len - o2->len _also_ has type
unsigned int; it has completely well-defined semantics, and the result
is some non-negative integer, which is always representable in a long
long. But this means that if the conditional triggers, we are
guaranteed to return a positive value from compare_blob.

In this case it could be fixed by

-       res = o1->len - o2->len;
+       res = (long long)o1->len - (long long)o2->len;

but I'd rather eliminate the usually broken 'return a - b;' idiom.
Reviewed-by: default avatarJeff Layton <jlayton@primarydata.com>
Signed-off-by: default avatarRasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: default avatarJ. Bruce Fields <bfields@redhat.com>
Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      b67dd5ae
    • Bart Van Assche's avatar
      blk-mq: Fix a use-after-free · d1749b1a
      Bart Van Assche authored 
      commit 45a9c9d9 upstream.

blk-mq users are allowed to free the memory request_queue.tag_set
points at after blk_cleanup_queue() has finished but before
blk_release_queue() has started. This can happen e.g. in the SCSI
core. The SCSI core namely embeds the tag_set structure in a SCSI
host structure. The SCSI host structure is freed by
scsi_host_dev_release(). This function is called after
blk_cleanup_queue() finished but can be called before
blk_release_queue().

This means that it is not safe to access request_queue.tag_set from
inside blk_release_queue(). Hence remove the blk_sync_queue() call
from blk_release_queue(). This call is not necessary - outstanding
requests must have finished before blk_release_queue() is
called. Additionally, move the blk_mq_free_queue() call from
blk_release_queue() to blk_cleanup_queue() to avoid that struct
request_queue.tag_set gets accessed after it has been freed.

This patch avoids that the following kernel oops can be triggered
when deleting a SCSI host for which scsi-mq was enabled:

Call Trace:
 [<ffffffff8109a7c4>] lock_acquire+0xc4/0x270
 [<ffffffff814ce111>] mutex_lock_nested+0x61/0x380
 [<ffffffff812575f0>] blk_mq_free_queue+0x30/0x180
 [<ffffffff8124d654>] blk_release_queue+0x84/0xd0
 [<ffffffff8126c29b>] kobject_cleanup+0x7b/0x1a0
 [<ffffffff8126c140>] kobject_put+0x30/0x70
 [<ffffffff81245895>] blk_put_queue+0x15/0x20
 [<ffffffff8125c409>] disk_release+0x99/0xd0
 [<ffffffff8133d056>] device_release+0x36/0xb0
 [<ffffffff8126c29b>] kobject_cleanup+0x7b/0x1a0
 [<ffffffff8126c140>] kobject_put+0x30/0x70
 [<ffffffff8125a78a>] put_disk+0x1a/0x20
 [<ffffffff811d4cb5>] __blkdev_put+0x135/0x1b0
 [<ffffffff811d56a0>] blkdev_put+0x50/0x160
 [<ffffffff81199eb4>] kill_block_super+0x44/0x70
 [<ffffffff8119a2a4>] deactivate_locked_super+0x44/0x60
 [<ffffffff8119a87e>] deactivate_super+0x4e/0x70
 [<ffffffff811b9833>] cleanup_mnt+0x43/0x90
 [<ffffffff811b98d2>] __cleanup_mnt+0x12/0x20
 [<ffffffff8107252c>] task_work_run+0xac/0xe0
 [<ffffffff81002c01>] do_notify_resume+0x61/0xa0
 [<ffffffff814d2c58>] int_signal+0x12/0x17
Signed-off-by: default avatarBart Van Assche <bvanassche@acm.org>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Robert Elliott <elliott@hp.com>
Cc: Ming Lei <ming.lei@canonical.com>
Cc: Alexander Gordeev <agordeev@redhat.com>
Signed-off-by: default avatarJens Axboe <axboe@fb.com>
[ kamal: backport to 3.13-stable: context ]
Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      d1749b1a
    • Luis Henriques's avatar
      thermal: Fix error path in thermal_init() · 42f57ad5
      Luis Henriques authored 
      commit 9d367e5e upstream.

thermal_unregister_governors() and class_unregister() were being called in
the wrong order.

Fixes: 80a26a5c ("Thermal: build thermal governors into thermal_sys module")
Signed-off-by: default avatarLuis Henriques <luis.henriques@canonical.com>
Signed-off-by: default avatarZhang Rui <rui.zhang@intel.com>
Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      42f57ad5
    • Takashi Iwai's avatar
      KEYS: Fix stale key registration at error path · 6be18a20
      Takashi Iwai authored 
      commit b26bdde5 upstream.

When loading encrypted-keys module, if the last check of
aes_get_sizes() in init_encrypted() fails, the driver just returns an
error without unregistering its key type.  This results in the stale
entry in the list.  In addition to memory leaks, this leads to a kernel
crash when registering a new key type later.

This patch fixes the problem by swapping the calls of aes_get_sizes()
and register_key_type(), and releasing resources properly at the error
paths.

Bugzilla: https://bugzilla.opensuse.org/show_bug.cgi?id=908163Signed-off-by: default avatarTakashi Iwai <tiwai@suse.de>
Signed-off-by: default avatarMimi Zohar <zohar@linux.vnet.ibm.com>
Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      6be18a20
    • Takashi Iwai's avatar
      ALSA: usb-audio: Don't resubmit pending URBs at MIDI error recovery · 05bf11a1
      Takashi Iwai authored 
      commit 66139a48 upstream.

In snd_usbmidi_error_timer(), the driver tries to resubmit MIDI input
URBs to reactivate the MIDI stream, but this causes the error when
some of URBs are still pending like:

 WARNING: CPU: 0 PID: 0 at ../drivers/usb/core/urb.c:339 usb_submit_urb+0x5f/0x70()
 URB ef705c40 submitted while active
 CPU: 0 PID: 0 Comm: swapper/0 Not tainted 3.16.6-2-desktop #1
 Hardware name: FOXCONN TPS01/TPS01, BIOS 080015  03/23/2010
  c0984bfa f4009ed4 c078deaf f4009ee4 c024c884 c09a135c f4009f00 00000000
  c0984bfa 00000153 c061ac4f c061ac4f 00000009 00000001 ef705c40 e854d1c0
  f4009eec c024c8d3 00000009 f4009ee4 c09a135c f4009f00 f4009f04 c061ac4f
 Call Trace:
  [<c0205df6>] try_stack_unwind+0x156/0x170
  [<c020482a>] dump_trace+0x5a/0x1b0
  [<c0205e56>] show_trace_log_lvl+0x46/0x50
  [<c02049d1>] show_stack_log_lvl+0x51/0xe0
  [<c0205eb7>] show_stack+0x27/0x50
  [<c078deaf>] dump_stack+0x45/0x65
  [<c024c884>] warn_slowpath_common+0x84/0xa0
  [<c024c8d3>] warn_slowpath_fmt+0x33/0x40
  [<c061ac4f>] usb_submit_urb+0x5f/0x70
  [<f7974104>] snd_usbmidi_submit_urb+0x14/0x60 [snd_usbmidi_lib]
  [<f797483a>] snd_usbmidi_error_timer+0x6a/0xa0 [snd_usbmidi_lib]
  [<c02570c0>] call_timer_fn+0x30/0x130
  [<c0257442>] run_timer_softirq+0x1c2/0x260
  [<c0251493>] __do_softirq+0xc3/0x270
  [<c0204732>] do_softirq_own_stack+0x22/0x30
  [<c025186d>] irq_exit+0x8d/0xa0
  [<c0795228>] smp_apic_timer_interrupt+0x38/0x50
  [<c0794a3c>] apic_timer_interrupt+0x34/0x3c
  [<c0673d9e>] cpuidle_enter_state+0x3e/0xd0
  [<c028bb8d>] cpu_idle_loop+0x29d/0x3e0
  [<c028bd23>] cpu_startup_entry+0x53/0x60
  [<c0bfac1e>] start_kernel+0x415/0x41a

For avoiding these errors, check the pending URBs and skip
resubmitting such ones.
Reported-and-tested-by: default avatarStefan Seyfried <stefan.seyfried@googlemail.com>
Acked-by: default avatarClemens Ladisch <clemens@ladisch.de>
Signed-off-by: default avatarTakashi Iwai <tiwai@suse.de>
Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      05bf11a1
    • Stephane Grosjean's avatar
      can: peak_usb: fix cleanup sequence order in case of error during init · bffd0828
      Stephane Grosjean authored 
      commit af35d0f1 upstream.

This patch sets the correct reverse sequence order to the instructions
set to run, when any failure occurs during the initialization steps.
It also adds the missing unregistration call of the can device if the
failure appears after having been registered.
Signed-off-by: default avatarStephane Grosjean <s.grosjean@peak-system.com>
Signed-off-by: default avatarMarc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      bffd0828
    • Stephane Grosjean's avatar
      can: peak_usb: fix memset() usage · 976cd7fd
      Stephane Grosjean authored 
      commit dc50ddcd upstream.

This patchs fixes a misplaced call to memset() that fills the request
buffer with 0. The problem was with sending PCAN_USBPRO_REQ_FCT
requests, the content set by the caller was thus lost.

With this patch, the memory area is zeroed only when requesting info
from the device.
Signed-off-by: default avatarStephane Grosjean <s.grosjean@peak-system.com>
Signed-off-by: default avatarMarc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      976cd7fd
    • Takashi Iwai's avatar
      ALSA: hda - Fix built-in mic at resume on Lenovo Ideapad S210 · debc8b31
      Takashi Iwai authored 
      commit fedb2245 upstream.

The built-in mic boost volume gets almost muted after suspend/resume
on Lenovo Ideapad S210.

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=88121Reported-and-tested-by: default avatarRoman Kagan <rkagan@mail.ru>
Signed-off-by: default avatarTakashi Iwai <tiwai@suse.de>
Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      debc8b31
    • Sonny Rao's avatar
      clocksource: arch_timer: Fix code to use physical timers when requested · 658576fe
      Sonny Rao authored 
      commit 0b46b8a7 upstream.

This is a bug fix for using physical arch timers when
the arch_timer_use_virtual boolean is false.  It restores the
arch_counter_get_cntpct() function after removal in

0d651e4e "clocksource: arch_timer: use virtual counters"

We need this on certain ARMv7 systems which are architected like this:

* The firmware doesn't know and doesn't care about hypervisor mode and
  we don't want to add the complexity of hypervisor there.

* The firmware isn't involved in SMP bringup or resume.

* The ARCH timer come up with an uninitialized offset between the
  virtual and physical counters.  Each core gets a different random
  offset.

* The device boots in "Secure SVC" mode.

* Nothing has touched the reset value of CNTHCTL.PL1PCEN or
  CNTHCTL.PL1PCTEN (both default to 1 at reset)

One example of such as system is RK3288 where it is much simpler to
use the physical counter since there's nobody managing the offset and
each time a core goes down and comes back up it will get reinitialized
to some other random value.

Fixes: 0d651e4e ("clocksource: arch_timer: use virtual counters")
Signed-off-by: default avatarSonny Rao <sonnyrao@chromium.org>
Acked-by: default avatarCatalin Marinas <catalin.marinas@arm.com>
Acked-by: default avatarDaniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: default avatarOlof Johansson <olof@lixom.net>
[ kamal: backport to 3.13-stable: context ]
Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      658576fe
  3. 28 Jan, 2015 21 commits
GitLab Nexedi Edition | About GitLab | About Nexedi | 沪ICP备2021021310号-2 | 沪ICP备2021021310号-7