Commit Graph

574754 Commits

Author SHA1 Message Date
Jan Kara
ed8ad83808 ext4: fix bh->b_state corruption
ext4 can update bh->b_state non-atomically in _ext4_get_block() and
ext4_da_get_block_prep(). Usually this is fine since bh is just a
temporary storage for mapping information on stack but in some cases it
can be fully living bh attached to a page. In such case non-atomic
update of bh->b_state can race with an atomic update which then gets
lost. Usually when we are mapping bh and thus updating bh->b_state
non-atomically, nobody else touches the bh and so things work out fine
but there is one case to especially worry about: ext4_finish_bio() uses
BH_Uptodate_Lock on the first bh in the page to synchronize handling of
PageWriteback state. So when blocksize < pagesize, we can be atomically
modifying bh->b_state of a buffer that actually isn't under IO and thus
can race e.g. with delalloc trying to map that buffer. The result is
that we can mistakenly set / clear BH_Uptodate_Lock bit resulting in the
corruption of PageWriteback state or missed unlock of BH_Uptodate_Lock.

Fix the problem by always updating bh->b_state bits atomically.

CC: stable@vger.kernel.org
Reported-by: Nikolay Borisov <kernel@kyup.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2016-02-19 00:18:25 -05:00
Rasmus Villemoes
4fbbed46dc drm/nouveau: use post-decrement in error handling
We need to use post-decrement to get the dma_map_page undone also for
i==0, and to avoid some very unpleasant behaviour if dma_map_page
failed already at i==0.

Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Reviewed-by: Ben Skeggs <bskeggs@redhat.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
2016-02-19 13:36:05 +10:00
Maarten Lankhorst
5fff80bbdb drm/atomic: Allow for holes in connector state, v2.
Because we record connector_mask using 1 << drm_connector_index now
the connector_mask should stay the same even when other connectors
are removed. This was not the case with MST, in that case when removing
a connector all other connectors may change their index.

This is fixed by waiting until the first get_connector_state to allocate
connector_state, and force reallocation when state is too small.

As a side effect connector arrays no longer have to be preallocated,
and can be allocated on first use which means a less allocations in
the page flip only path.

Changes since v1:
- Whitespace. (Ville)
- Call ida_remove when destroying the connector. (Ville)
- u32 alloc -> int. (Ville)

Fixes: 14de6c44d1 ("drm/atomic: Remove drm_atomic_connectors_for_crtc.")
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Lyude <cpaul@redhat.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
2016-02-19 13:24:03 +10:00
Stephen Boyd
4462b4bbfc clk: gpio: Really allow an optional clock= DT property
We mis-merged the original patch from Russell here and so the
patch went almost all the way, except that we still failed to
probe when there wasn't a clocks property in the DT node. Allow
that case by making a negative value from
of_clk_get_parent_count() into "no parents", like the original
patch did.

Fixes: 7ed88aa2ef ("clk: fix clk-gpio.c with optional clock= DT property")
Cc: Russell King <rmk+kernel@arm.linux.org.uk>
Cc: Michael Turquette <mturquette@baylibre.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2016-02-18 19:10:22 -08:00
Dave Airlie
5441ea115e This pull request fixes GPU reset (which was disabled shortly after
V3D integration due to build breakage) and waits for idle in the
 presence of signals (which X likes to do a lot).
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Merge tag 'drm-vc4-fixes-2016-02-17' of github.com:anholt/linux into drm-fixes

This pull request fixes GPU reset (which was disabled shortly after
V3D integration due to build breakage) and waits for idle in the
presence of signals (which X likes to do a lot).

* tag 'drm-vc4-fixes-2016-02-17' of github.com:anholt/linux:
  drm/vc4: Use runtime PM to power cycle the device when the GPU hangs.
  drm/vc4: Enable runtime PM.
  drm/vc4: Fix spurious GPU resets due to BO reuse.
  drm/vc4: Drop error message on seqno wait timeouts.
  drm/vc4: Fix -ERESTARTSYS error return from BO waits.
  drm/vc4: Return an ERR_PTR from BO creation instead of NULL.
  drm/vc4: Fix the clear color for the first tile rendered.
  drm/vc4: Validate that WAIT_BO padding is cleared.
2016-02-19 12:50:00 +10:00
Dave Airlie
aaa7dd2ced Merge branch 'drm-fixes-4.5' of git://people.freedesktop.org/~agd5f/linux into drm-fixes
Just two small fixes in the ttm_tt_populate error handling; one for radeon,
one for amdgpu.

* 'drm-fixes-4.5' of git://people.freedesktop.org/~agd5f/linux:
  drm/radeon: use post-decrement in error handling
  drm/amdgpu: use post-decrement in error handling
2016-02-19 12:49:03 +10:00
Dave Airlie
42412b120d Merge tag 'drm-intel-fixes-2016-02-18' of git://anongit.freedesktop.org/drm-intel into drm-fixes
single g4x hpd fix.

* tag 'drm-intel-fixes-2016-02-18' of git://anongit.freedesktop.org/drm-intel:
  drm/i915: Fix hpd live status bits for g4x
2016-02-19 12:43:03 +10:00
Linus Torvalds
705d43dbe1 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/livepatching
Pull livepatching fixes from Jiri Kosina:

 - regression (from 4.4) fix for ordering issue, introduced by an
   earlier ftrace change, that broke live patching of modules.

   The fix replaces the ftrace module notifier by direct call in order
   to make the ordering guaranteed and well-defined.  The patch, from
   Jessica Yu, has been acked both by Steven and Rusty

 - error message fix from Miroslav Benes

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/livepatching:
  ftrace/module: remove ftrace module notifier
  livepatch: change the error message in asm/livepatch.h header files
2016-02-18 16:34:15 -08:00
Linus Torvalds
dd8fc10e60 SCSI fixes on 20160218
Two simple fixes.  One prevents a soft lockup on some target removal
 scenarios and the other prevents us trying to probe the marvell
 console device, which causes it to time out and need the bus
 resetting.
 
 Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
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Merge tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi

Pull SCSI fixes from James Bottomley:
 "Two simple fixes.

  One prevents a soft lockup on some target removal scenarios and the
  other prevents us trying to probe the marvell console device, which
  causes it to time out and need the bus resetting"

* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
  scsi: fix soft lockup in scsi_remove_target() on module removal
  SCSI: Add Marvell configuration device to VPD blacklist
2016-02-18 16:24:48 -08:00
Dmitry Safonov
52b4b950b5 mm: slab: free kmem_cache_node after destroy sysfs file
When slub_debug alloc_calls_show is enabled we will try to track
location and user of slab object on each online node, kmem_cache_node
structure and cpu_cache/cpu_slub shouldn't be freed till there is the
last reference to sysfs file.

This fixes the following panic:

   BUG: unable to handle kernel NULL pointer dereference at 0000000000000020
   IP:  list_locations+0x169/0x4e0
   PGD 257304067 PUD 438456067 PMD 0
   Oops: 0000 [#1] SMP
   CPU: 3 PID: 973074 Comm: cat ve: 0 Not tainted 3.10.0-229.7.2.ovz.9.30-00007-japdoll-dirty #2 9.30
   Hardware name: DEPO Computers To Be Filled By O.E.M./H67DE3, BIOS L1.60c 07/14/2011
   task: ffff88042a5dc5b0 ti: ffff88037f8d8000 task.ti: ffff88037f8d8000
   RIP: list_locations+0x169/0x4e0
   Call Trace:
     alloc_calls_show+0x1d/0x30
     slab_attr_show+0x1b/0x30
     sysfs_read_file+0x9a/0x1a0
     vfs_read+0x9c/0x170
     SyS_read+0x58/0xb0
     system_call_fastpath+0x16/0x1b
   Code: 5e 07 12 00 b9 00 04 00 00 3d 00 04 00 00 0f 4f c1 3d 00 04 00 00 89 45 b0 0f 84 c3 00 00 00 48 63 45 b0 49 8b 9c c4 f8 00 00 00 <48> 8b 43 20 48 85 c0 74 b6 48 89 df e8 46 37 44 00 48 8b 53 10
   CR2: 0000000000000020

Separated __kmem_cache_release from __kmem_cache_shutdown which now
called on slab_kmem_cache_release (after the last reference to sysfs
file object has dropped).

Reintroduced locking in free_partial as sysfs file might access cache's
partial list after shutdowning - partial revert of the commit
69cb8e6b7c ("slub: free slabs without holding locks").  Zap
__remove_partial and use remove_partial (w/o underscores) as
free_partial now takes list_lock which s partial revert for commit
1e4dd9461f ("slub: do not assert not having lock in removing freed
partial")

Signed-off-by: Dmitry Safonov <dsafonov@virtuozzo.com>
Suggested-by: Vladimir Davydov <vdavydov@virtuozzo.com>
Acked-by: Vladimir Davydov <vdavydov@virtuozzo.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-02-18 16:23:24 -08:00
Kirill A. Shutemov
1ac0b6dec6 ipc/shm: handle removed segments gracefully in shm_mmap()
remap_file_pages(2) emulation can reach file which represents removed
IPC ID as long as a memory segment is mapped.  It breaks expectations of
IPC subsystem.

Test case (rewritten to be more human readable, originally autogenerated
by syzkaller[1]):

	#define _GNU_SOURCE
	#include <stdlib.h>
	#include <sys/ipc.h>
	#include <sys/mman.h>
	#include <sys/shm.h>

	#define PAGE_SIZE 4096

	int main()
	{
		int id;
		void *p;

		id = shmget(IPC_PRIVATE, 3 * PAGE_SIZE, 0);
		p = shmat(id, NULL, 0);
		shmctl(id, IPC_RMID, NULL);
		remap_file_pages(p, 3 * PAGE_SIZE, 0, 7, 0);

	        return 0;
	}

The patch changes shm_mmap() and code around shm_lock() to propagate
locking error back to caller of shm_mmap().

[1] http://github.com/google/syzkaller

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Manfred Spraul <manfred@colorfullife.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-02-18 16:23:24 -08:00
Shuah Khan
64f0085001 MAINTAINERS: update Kselftest Framework mailing list
Kselftest Framework now has a dedicated mailing list linux-kselftest.
Update the entry in MAINTAINERS file.

Signed-off-by: Shuah Khan <shuahkh@osg.samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-02-18 16:23:24 -08:00
Toshi Kani
9273a8bbf5 devm_memremap_release(): fix memremap'd addr handling
The pmem driver calls devm_memremap() to map a persistent memory range.
When the pmem driver is unloaded, this memremap'd range is not released
so the kernel will leak a vma.

Fix devm_memremap_release() to handle a given memremap'd address
properly.

Signed-off-by: Toshi Kani <toshi.kani@hpe.com>
Acked-by: Dan Williams <dan.j.williams@intel.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Cc: Matthew Wilcox <willy@linux.intel.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-02-18 16:23:24 -08:00
Vaishali Thakkar
f8b74815a4 mm/hugetlb.c: fix incorrect proc nr_hugepages value
Currently incorrect default hugepage pool size is reported by proc
nr_hugepages when number of pages for the default huge page size is
specified twice.

When multiple huge page sizes are supported, /proc/sys/vm/nr_hugepages
indicates the current number of pre-allocated huge pages of the default
size.  Basically /proc/sys/vm/nr_hugepages displays default_hstate->
max_huge_pages and after boot time pre-allocation, max_huge_pages should
equal the number of pre-allocated pages (nr_hugepages).

Test case:

Note that this is specific to x86 architecture.

Boot the kernel with command line option 'default_hugepagesz=1G
hugepages=X hugepagesz=2M hugepages=Y hugepagesz=1G hugepages=Z'.  After
boot, 'cat /proc/sys/vm/nr_hugepages' and 'sysctl -a | grep hugepages'
returns the value X.  However, dmesg output shows that Z huge pages were
pre-allocated.

So, the root cause of the problem here is that the global variable
default_hstate_max_huge_pages is set if a default huge page size is
specified (directly or indirectly) on the command line.  After the command
line processing in hugetlb_init, if default_hstate_max_huge_pages is set,
the value is assigned to default_hstae.max_huge_pages.  However,
default_hstate.max_huge_pages may have already been set based on the
number of pre-allocated huge pages of default_hstate size.

The solution to this problem is if hstate->max_huge_pages is already set
then it should not set as a result of global max_huge_pages value.
Basically if the value of the variable hugepages is set multiple times on
a command line for a specific supported hugepagesize then proc layer
should consider the last specified value.

Signed-off-by: Vaishali Thakkar <vaishali.thakkar@oracle.com>
Reviewed-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Hillf Danton <hillf.zj@alibaba-inc.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-02-18 16:23:24 -08:00
Hugh Dickins
457a98b080 mm, x86: fix pte_page() crash in gup_pte_range()
Commit 3565fce3a6 ("mm, x86: get_user_pages() for dax mappings") has
moved up the pte_page(pte) in x86's fast gup_pte_range(), for no
discernible reason: put it back where it belongs, after the pte_flags
check and the pfn_valid cross-check.

That may be the cause of the NULL pointer dereference in
gup_pte_range(), seen when vfio called vaddr_get_pfn() when starting a
qemu-kvm based VM.

Signed-off-by: Hugh Dickins <hughd@google.com>
Reported-by: Michael Long <Harn-Solo@gmx.de>
Tested-by: Michael Long <Harn-Solo@gmx.de>
Acked-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-02-18 16:23:24 -08:00
Jeff Layton
0918f1c309 fsnotify: turn fsnotify reaper thread into a workqueue job
We don't require a dedicated thread for fsnotify cleanup.  Switch it
over to a workqueue job instead that runs on the system_unbound_wq.

In the interest of not thrashing the queued job too often when there are
a lot of marks being removed, we delay the reaper job slightly when
queueing it, to allow several to gather on the list.

Signed-off-by: Jeff Layton <jeff.layton@primarydata.com>
Tested-by: Eryu Guan <guaneryu@gmail.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: Eric Paris <eparis@parisplace.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-02-18 16:23:24 -08:00
Jeff Layton
13d34ac6e5 Revert "fsnotify: destroy marks with call_srcu instead of dedicated thread"
This reverts commit c510eff6be ("fsnotify: destroy marks with
call_srcu instead of dedicated thread").

Eryu reported that he was seeing some OOM kills kick in when running a
testcase that adds and removes inotify marks on a file in a tight loop.

The above commit changed the code to use call_srcu to clean up the
marks.  While that does (in principle) work, the srcu callback job is
limited to cleaning up entries in small batches and only once per jiffy.
It's easily possible to overwhelm that machinery with too many call_srcu
callbacks, and Eryu's reproduer did just that.

There's also another potential problem with using call_srcu here.  While
you can obviously sleep while holding the srcu_read_lock, the callbacks
run under local_bh_disable, so you can't sleep there.

It's possible when putting the last reference to the fsnotify_mark that
we'll end up putting a chain of references including the fsnotify_group,
uid, and associated keys.  While I don't see any obvious ways that that
could occurs, it's probably still best to avoid using call_srcu here
after all.

This patch reverts the above patch.  A later patch will take a different
approach to eliminated the dedicated thread here.

Signed-off-by: Jeff Layton <jeff.layton@primarydata.com>
Reported-by: Eryu Guan <guaneryu@gmail.com>
Tested-by: Eryu Guan <guaneryu@gmail.com>
Cc: Jan Kara <jack@suse.com>
Cc: Eric Paris <eparis@parisplace.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-02-18 16:23:24 -08:00
Kirill A. Shutemov
48f7df3294 mm: fix regression in remap_file_pages() emulation
Grazvydas Ignotas has reported a regression in remap_file_pages()
emulation.

Testcase:
	#define _GNU_SOURCE
	#include <assert.h>
	#include <stdlib.h>
	#include <stdio.h>
	#include <sys/mman.h>

	#define SIZE    (4096 * 3)

	int main(int argc, char **argv)
	{
		unsigned long *p;
		long i;

		p = mmap(NULL, SIZE, PROT_READ | PROT_WRITE,
				MAP_SHARED | MAP_ANONYMOUS, -1, 0);
		if (p == MAP_FAILED) {
			perror("mmap");
			return -1;
		}

		for (i = 0; i < SIZE / 4096; i++)
			p[i * 4096 / sizeof(*p)] = i;

		if (remap_file_pages(p, 4096, 0, 1, 0)) {
			perror("remap_file_pages");
			return -1;
		}

		if (remap_file_pages(p, 4096 * 2, 0, 1, 0)) {
			perror("remap_file_pages");
			return -1;
		}

		assert(p[0] == 1);

		munmap(p, SIZE);

		return 0;
	}

The second remap_file_pages() fails with -EINVAL.

The reason is that remap_file_pages() emulation assumes that the target
vma covers whole area we want to over map.  That assumption is broken by
first remap_file_pages() call: it split the area into two vma.

The solution is to check next adjacent vmas, if they map the same file
with the same flags.

Fixes: c8d78c1823 ("mm: replace remap_file_pages() syscall with emulation")
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reported-by: Grazvydas Ignotas <notasas@gmail.com>
Tested-by: Grazvydas Ignotas <notasas@gmail.com>
Cc: <stable@vger.kernel.org>	[4.0+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-02-18 16:23:24 -08:00
Kirill A. Shutemov
69a8ec2d81 thp, dax: do not try to withdraw pgtable from non-anon VMA
DAX doesn't deposit pgtables when it maps huge pages: nothing to
withdraw. It can lead to crash.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Matthew Wilcox <willy@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-02-18 16:23:24 -08:00
Takashi Iwai
67ec1072b0 ALSA: pcm: Fix rwsem deadlock for non-atomic PCM stream
A non-atomic PCM stream may take snd_pcm_link_rwsem rw semaphore twice
in the same code path, e.g. one in snd_pcm_action_nonatomic() and
another in snd_pcm_stream_lock().  Usually this is OK, but when a
write lock is issued between these two read locks, the problem
happens: the write lock is blocked due to the first reade lock, and
the second read lock is also blocked by the write lock.  This
eventually deadlocks.

The reason is the way rwsem manages waiters; it's queued like FIFO, so
even if the writer itself doesn't take the lock yet, it blocks all the
waiters (including reads) queued after it.

As a workaround, in this patch, we replace the standard down_write()
with an spinning loop.  This is far from optimal, but it's good
enough, as the spinning time is supposed to be relatively short for
normal PCM operations, and the code paths requiring the write lock
aren't called so often.

Reported-by: Vinod Koul <vinod.koul@intel.com>
Tested-by: Ramesh Babu <ramesh.babu@intel.com>
Cc: <stable@vger.kernel.org> # v3.18+
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2016-02-18 11:27:52 +01:00
Toshi Kani
f4eafd8bcd x86/mm: Fix vmalloc_fault() to handle large pages properly
A kernel page fault oops with the callstack below was observed
when a read syscall was made to a pmem device after a huge amount
(>512GB) of vmalloc ranges was allocated by ioremap() on a x86_64
system:

     BUG: unable to handle kernel paging request at ffff880840000ff8
     IP: vmalloc_fault+0x1be/0x300
     PGD c7f03a067 PUD 0
     Oops: 0000 [#1] SM
     Call Trace:
        __do_page_fault+0x285/0x3e0
        do_page_fault+0x2f/0x80
        ? put_prev_entity+0x35/0x7a0
        page_fault+0x28/0x30
        ? memcpy_erms+0x6/0x10
        ? schedule+0x35/0x80
        ? pmem_rw_bytes+0x6a/0x190 [nd_pmem]
        ? schedule_timeout+0x183/0x240
        btt_log_read+0x63/0x140 [nd_btt]
         :
        ? __symbol_put+0x60/0x60
        ? kernel_read+0x50/0x80
        SyS_finit_module+0xb9/0xf0
        entry_SYSCALL_64_fastpath+0x1a/0xa4

Since v4.1, ioremap() supports large page (pud/pmd) mappings in
x86_64 and PAE.  vmalloc_fault() however assumes that the vmalloc
range is limited to pte mappings.

vmalloc faults do not normally happen in ioremap'd ranges since
ioremap() sets up the kernel page tables, which are shared by
user processes.  pgd_ctor() sets the kernel's PGD entries to
user's during fork().  When allocation of the vmalloc ranges
crosses a 512GB boundary, ioremap() allocates a new pud table
and updates the kernel PGD entry to point it.  If user process's
PGD entry does not have this update yet, a read/write syscall
to the range will cause a vmalloc fault, which hits the Oops
above as it does not handle a large page properly.

Following changes are made to vmalloc_fault().

64-bit:

 - No change for the PGD sync operation as it handles large
   pages already.
 - Add pud_huge() and pmd_huge() to the validation code to
   handle large pages.
 - Change pud_page_vaddr() to pud_pfn() since an ioremap range
   is not directly mapped (while the if-statement still works
   with a bogus addr).
 - Change pmd_page() to pmd_pfn() since an ioremap range is not
   backed by struct page (while the if-statement still works
   with a bogus addr).

32-bit:
 - No change for the sync operation since the index3 PGD entry
   covers the entire vmalloc range, which is always valid.
   (A separate change to sync PGD entry is necessary if this
    memory layout is changed regardless of the page size.)
 - Add pmd_huge() to the validation code to handle large pages.
   This is for completeness since vmalloc_fault() won't happen
   in ioremap'd ranges as its PGD entry is always valid.

Reported-by: Henning Schild <henning.schild@siemens.com>
Signed-off-by: Toshi Kani <toshi.kani@hpe.com>
Acked-by: Borislav Petkov <bp@alien8.de>
Cc: <stable@vger.kernel.org> # 4.1+
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Luis R. Rodriguez <mcgrof@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Toshi Kani <toshi.kani@hp.com>
Cc: linux-mm@kvack.org
Cc: linux-nvdimm@lists.01.org
Link: http://lkml.kernel.org/r/1455758214-24623-1-git-send-email-toshi.kani@hpe.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-02-18 09:02:59 +01:00
Jessica Yu
7dcd182bec ftrace/module: remove ftrace module notifier
Remove the ftrace module notifier in favor of directly calling
ftrace_module_enable() and ftrace_release_mod() in the module loader.
Hard-coding the function calls directly in the module loader removes
dependence on the module notifier call chain and provides better
visibility and control over what gets called when, which is important
to kernel utilities such as livepatch.

This fixes a notifier ordering issue in which the ftrace module notifier
(and hence ftrace_module_enable()) for coming modules was being called
after klp_module_notify(), which caused livepatch modules to initialize
incorrectly. This patch removes dependence on the module notifier call
chain in favor of hard coding the corresponding function calls in the
module loader. This ensures that ftrace and livepatch code get called in
the correct order on patch module load and unload.

Fixes: 5156dca34a ("ftrace: Fix the race between ftrace and insmod")
Signed-off-by: Jessica Yu <jeyu@redhat.com>
Reviewed-by: Steven Rostedt <rostedt@goodmis.org>
Reviewed-by: Petr Mladek <pmladek@suse.cz>
Acked-by: Rusty Russell <rusty@rustcorp.com.au>
Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2016-02-17 22:14:06 +01:00
Linus Torvalds
2850713576 Merge branch 'for-linus' of git://git.kernel.dk/linux-block
Pull block fixes from Jens Axboe:
 "A collection of fixes from the past few weeks that should go into 4.5.
  This contains:

   - Overflow fix for sysfs discard show function from Alan.

   - A stacking limit init fix for max_dev_sectors, so we don't end up
     artificially capping some use cases.  From Keith.

   - Have blk-mq proper end unstarted requests on a dying queue, instead
     of pushing that to the driver.  From Keith.

   - NVMe:
        - Update to Kconfig description for NVME_SCSI, since it was
          vague and having it on is important for some SUSE distros.
          From Christoph.
        - Set of fixes from Keith, around surprise removal. Also kills
          the no-merge flag, so it supports merging.

   - Set of fixes for lightnvm from Matias, Javier, and Wenwei.

   - Fix null_blk oops when asked for lightnvm, but not available.  From
     Matias.

   - Copy-to-user EINTR fix from Hannes, fixing a case where SG_IO fails
     if interrupted by a signal.

   - Two floppy fixes from Jiri, fixing signal handling and blocking
     open.

   - A use-after-free fix for O_DIRECT, from Mike Krinkin.

   - A block module ref count fix from Roman Pen.

   - An fs IO wait accounting fix for O_DSYNC from Stephane Gasparini.

   - Smaller reallo fix for xen-blkfront from Bob Liu.

   - Removal of an unused struct member in the deadline IO scheduler,
     from Tahsin.

   - Also from Tahsin, properly initialize inode struct members
     associated with cgroup writeback, if enabled.

   - From Tejun, ensure that we keep the superblock pinned during cgroup
     writeback"

* 'for-linus' of git://git.kernel.dk/linux-block: (25 commits)
  blk: fix overflow in queue_discard_max_hw_show
  writeback: initialize inode members that track writeback history
  writeback: keep superblock pinned during cgroup writeback association switches
  bio: return EINTR if copying to user space got interrupted
  NVMe: Rate limit nvme IO warnings
  NVMe: Poll device while still active during remove
  NVMe: Requeue requests on suspended queues
  NVMe: Allow request merges
  NVMe: Fix io incapable return values
  blk-mq: End unstarted requests on dying queue
  block: Initialize max_dev_sectors to 0
  null_blk: oops when initializing without lightnvm
  block: fix module reference leak on put_disk() call for cgroups throttle
  nvme: fix Kconfig description for BLK_DEV_NVME_SCSI
  kernel/fs: fix I/O wait not accounted for RW O_DSYNC
  floppy: refactor open() flags handling
  lightnvm: allow to force mm initialization
  lightnvm: check overflow and correct mlc pairs
  lightnvm: fix request intersection locking in rrpc
  lightnvm: warn if irqs are disabled in lock laddr
  ...
2016-02-17 11:59:23 -08:00
Linus Torvalds
c28b947d04 DeviceTree fixes for 4.5-rc5:
- Fix irq msi-map calculation for nonzero rid-base.
 
 - Binding doc updates for GICv3, fsl-imx-uart, and S3C RTC.
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Merge tag 'devicetree-fixes-for-4.5-2' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux

Pull DeviceTree fixes from Rob Herring:

 - Fix irq msi-map calculation for nonzero rid-base.

 - Binding doc updates for GICv3, fsl-imx-uart, and S3C RTC.

* tag 'devicetree-fixes-for-4.5-2' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux:
  rtc: s3c: Document required clocks in the DT binding
  serial: fsl-imx-uart: Fix typo in fsl,dte-mode description
  dt-bindings: arm, gic-v3: require that reserved cells are always 0
  of/irq: Fix msi-map calculation for nonzero rid-base
2016-02-17 11:50:53 -08:00
Linus Torvalds
35683dd326 Merge branch 'drm-fixes' of git://people.freedesktop.org/~airlied/linux
Pull drm fixes from Dave Airlie:
 "This has two main sets of fixes:

   - A bunch of Exynos fixes, mainly for their MIC component.

   - vblank regression fixes from Mario, apparantly some changes in 4.4
     caused some vblank breakage on radeon/nouveau, this set fixes all
     the issues seen.

  There is also a revert of one of the MST changse, that I was
  overzealous in including, that broke 30" MST monitors, and two qxl
  fixes"

* 'drm-fixes' of git://people.freedesktop.org/~airlied/linux:
  drm/qxl: fix erroneous return value
  drm/nouveau/display: Enable vblank irqs after display engine is on again.
  drm/radeon/pm: Handle failure of drm_vblank_get.
  drm: Fix treatment of drm_vblank_offdelay in drm_vblank_on() (v2)
  drm: Fix drm_vblank_pre/post_modeset regression from Linux 4.4
  drm: Prevent vblank counter bumps > 1 with active vblank clients. (v2)
  drm: No-Op redundant calls to drm_vblank_off() (v2)
  drm/qxl: use kmalloc_array to alloc reloc_info in qxl_process_single_command
  Revert "drm/dp/mst: change MST detection scheme"
  drm/exynos/decon: fix disable clocks order
  drm/exynos: fix incorrect cpu address for dma_mmap_attrs()
  drm/exynos: exynos5433_decon: fix wrong state in decon_vblank_enable
  drm/exynos: exynos5433_decon: fix wrong state assignment in decon_enable
  drm/exynos: dsi: restore support for drm bridge
  drm/exynos: mic: make all functions static
  drm/exynos: mic: convert to component framework
  drm/exynos: mic: use devm_clk interface
  drm/exynos: fix types for compilation on 64bit architectures
  drm/exynos: ipp: fix incorrect format specifiers in debug messages
  drm/exynos: depend on ARCH_EXYNOS for DRM_EXYNOS
2016-02-17 11:45:10 -08:00
Linus Torvalds
a9f70bd4e7 This includes two fixes.
The first is something that has come up a few times and has been
 worked out individually, but it's come up now enough that the problem
 should be generic. Tracepoints are protected by RCU sched. There are
 several tracepoints within core infrastructure like kfree().
 If a tracepoint is called when the CPU is going down, or when it's
 coming up but has yet to be recognized by RCU, a RCU warning is
 triggered. This is a true bug as that tracepoint is not protected by
 RCU. Usually, this is taken care of by testing for cpu online as
 a tracepoint condition. But as this is happening more often, moving
 it from a individual tracepoint to a check in the tracepoint infrastructure
 is more robust.
 
 Note, there is now a duplicate of a cpu online test, because this update
 does not remove the individual checks. But the overhead is small enough
 that the removal can be done in another release.
 
 The second change is strange linker breakage due to the branch tracer's
 builtin_constant_p() check failing, and treating the condition as a
 variable instead of a constant. Arnd Bergmann found that this can be
 fixed by testing !!(cond) instead of just (cond).
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Merge tag 'trace-fixes-v4.5-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing fixes from Steven Rostedt:
 "This includes two fixes.

  The first is something that has come up a few times and has been
  worked out individually, but it's come up now enough that the problem
  should be generic.  Tracepoints are protected by RCU sched.  There are
  several tracepoints within core infrastructure like kfree().  If a
  tracepoint is called when the CPU is going down, or when it's coming
  up but has yet to be recognized by RCU, a RCU warning is triggered.

  This is a true bug as that tracepoint is not protected by RCU.
  Usually, this is taken care of by testing for cpu online as a
  tracepoint condition.  But as this is happening more often, moving it
  from a individual tracepoint to a check in the tracepoint
  infrastructure is more robust.

  Note, there is now a duplicate of a cpu online test, because this
  update does not remove the individual checks.  But the overhead is
  small enough that the removal can be done in another release.

  The second change is strange linker breakage due to the branch
  tracer's builtin_constant_p() check failing, and treating the
  condition as a variable instead of a constant.  Arnd Bergmann found
  that this can be fixed by testing !!(cond) instead of just (cond)"

* tag 'trace-fixes-v4.5-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracing: Fix freak link error caused by branch tracer
  tracepoints: Do not trace when cpu is offline
2016-02-17 11:35:41 -08:00
Alan
18f922d037 blk: fix overflow in queue_discard_max_hw_show
We get this right for queue_discard_max_show but not max_hw_show. Follow the
same pattern as queue_discard_max_show instead so that we don't truncate.

Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-02-17 10:20:42 -07:00
Alexey Kardashevskiy
6ecad912a0 powerpc/ioda: Set "read" permission when "write" is set
Quite often drivers set only "write" permission assuming that this
includes "read" permission as well and this works on plenty of
platforms. However IODA2 is strict about this and produces an EEH when
"read" permission is not set and reading happens.

This adds a workaround in the IODA code to always add the "read" bit
when the "write" bit is set.

Fixes: 10b35b2b74 ("powerpc/powernv: Do not set "read" flag if direction==DMA_NONE")
Cc: stable@vger.kernel.org # 4.2+
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Tested-by: Douglas Miller <dougmill@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-02-17 23:52:17 +11:00
Marek Szyprowski
722ec35f7f arm64: dma-mapping: fix handling of devices registered before arch_initcall
This patch ensures that devices, which got registered before arch_initcall
will be handled correctly by IOMMU-based DMA-mapping code.

Cc: <stable@vger.kernel.org>
Fixes: 13b8629f65 ("arm64: Add IOMMU dma_ops")
Acked-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-02-17 11:48:01 +00:00
Ville Syrjälä
8d409cb3e8 drm/i915: Fix hpd live status bits for g4x
Looks like g4x hpd live status bits actually agree with the spec. At
least they do on the machine I have, and apparently on Nick Bowler's
g4x as well.

So gm45 may be the only platform where they don't agree. At least
that seems to be the case based on the (somewhat incomplete)
logs/dumps in [1], and Daniel has also tested this on his gm45
sometime in the past.

So let's change the bits to match the spec on g4x. That actually makes
the g4x bits identical to vlv/chv so we can just share the code
between those platforms, leaving gm45 as the special case.

[1] https://bugzilla.kernel.org/show_bug.cgi?id=52361

Cc: Shashank Sharma <shashank.sharma@intel.com>
Cc: Sonika Jindal <sonika.jindal@intel.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Nick Bowler <nbowler@draconx.ca>
References: https://lists.freedesktop.org/archives/dri-devel/2016-February/100382.html
Reported-by: Nick Bowler <nbowler@draconx.ca>
Cc: stable@vger.kernel.org
Fixes: 237ed86c69 ("drm/i915: Check live status before reading edid")
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1455127145-20087-1-git-send-email-ville.syrjala@linux.intel.com
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
(cherry picked from commit 0780cd36c7)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
2016-02-17 11:52:54 +02:00
Thomas Gleixner
059fcd8cd1 perf/core: Plug potential memory leak in CPU_UP_PREPARE
If CPU_UP_PREPARE is called it is not guaranteed, that a previously allocated
and assigned hash has been freed already, but perf_event_init_cpu()
unconditionally allocates and assignes a new hash if the swhash is referenced.
By overwriting the pointer the existing hash is not longer accessible.

Verify that there is no hash assigned on this cpu before allocating and
assigning a new one.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Link: http://lkml.kernel.org/r/20160209201007.843269966@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-02-17 10:37:30 +01:00
Thomas Gleixner
27ca9236c9 perf/core: Remove the bogus and dangerous CPU_DOWN_FAILED hotplug state
If CPU_DOWN_PREPARE fails the perf hotplug notifier is called for
CPU_DOWN_FAILED and calls perf_event_init_cpu(), which checks whether the
swhash is referenced. If yes it allocates a new hash and stores the pointer in
the per cpu data structure.

But at this point the cpu is still online, so there must be a valid hash
already. By overwriting the pointer the existing hash is not longer
accessible.

Remove the CPU_DOWN_FAILED state, as there is nothing to (re)allocate.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Link: http://lkml.kernel.org/r/20160209201007.763417379@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-02-17 10:37:29 +01:00
Thomas Gleixner
b4f75d44be perf/core: Remove bogus UP_CANCELED hotplug state
If CPU_UP_PREPARE fails the perf hotplug code calls perf_event_exit_cpu(),
which is a pointless exercise. The cpu is not online, so the smp function
calls return -ENXIO. So the result is a list walk to call noops.

Remove it.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Link: http://lkml.kernel.org/r/20160209201007.682184765@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-02-17 10:37:28 +01:00
Michael S. Tsirkin
4e7f9df258 hpet: Drop stale URLs
Looks like the HPET spec at intel.com got moved.
It isn't hard to find so drop the link, just mention
the revision assumed.

Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Clemens Ladisch <clemens@ladisch.de>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: linux-doc@vger.kernel.org
Link: http://lkml.kernel.org/r/1455145462-3877-1-git-send-email-mst@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-02-17 09:39:56 +01:00
Stefan Haberland
12d319b920 s390/dasd: fix performance drop
Commit ca369d51b ("sd: Fix device-imposed transfer length limits")
introduced a new queue limit max_dev_sectors which limits the maximum
sectors for requests. The default value leads to small dasd requests
and therefor to a performance drop.
Set the max_dev_sectors value to the same value as the max_hw_sectors
to use the maximum available request size for DASD devices.

Signed-off-by: Stefan Haberland <sth@linux.vnet.ibm.com>
Cc: stable@vger.kernel.org # 4.4+
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-02-17 09:24:07 +01:00
Toshi Kani
a82eee7424 x86/uaccess/64: Handle the caching of 4-byte nocache copies properly in __copy_user_nocache()
Data corruption issues were observed in tests which initiated
a system crash/reset while accessing BTT devices.  This problem
is reproducible.

The BTT driver calls pmem_rw_bytes() to update data in pmem
devices.  This interface calls __copy_user_nocache(), which
uses non-temporal stores so that the stores to pmem are
persistent.

__copy_user_nocache() uses non-temporal stores when a request
size is 8 bytes or larger (and is aligned by 8 bytes).  The
BTT driver updates the BTT map table, which entry size is
4 bytes.  Therefore, updates to the map table entries remain
cached, and are not written to pmem after a crash.

Change __copy_user_nocache() to use non-temporal store when
a request size is 4 bytes.  The change extends the current
byte-copy path for a less-than-8-bytes request, and does not
add any overhead to the regular path.

Reported-and-tested-by: Micah Parrish <micah.parrish@hpe.com>
Reported-and-tested-by: Brian Boylston <brian.boylston@hpe.com>
Signed-off-by: Toshi Kani <toshi.kani@hpe.com>
Cc: <stable@vger.kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bp@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Luis R. Rodriguez <mcgrof@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Toshi Kani <toshi.kani@hp.com>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Cc: linux-nvdimm@lists.01.org
Link: http://lkml.kernel.org/r/1455225857-12039-3-git-send-email-toshi.kani@hpe.com
[ Small readability edits. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-02-17 09:10:23 +01:00
Toshi Kani
ee9737c924 x86/uaccess/64: Make the __copy_user_nocache() assembly code more readable
Add comments to __copy_user_nocache() to clarify its procedures
and alignment requirements.

Also change numeric branch target labels to named local labels.

No code changed:

 arch/x86/lib/copy_user_64.o:

    text    data     bss     dec     hex filename
    1239       0       0    1239     4d7 copy_user_64.o.before
    1239       0       0    1239     4d7 copy_user_64.o.after

 md5:
    58bed94c2db98c1ca9a2d46d0680aaae  copy_user_64.o.before.asm
    58bed94c2db98c1ca9a2d46d0680aaae  copy_user_64.o.after.asm

Signed-off-by: Toshi Kani <toshi.kani@hpe.com>
Cc: <stable@vger.kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bp@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Luis R. Rodriguez <mcgrof@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Toshi Kani <toshi.kani@hp.com>
Cc: brian.boylston@hpe.com
Cc: dan.j.williams@intel.com
Cc: linux-nvdimm@lists.01.org
Cc: micah.parrish@hpe.com
Cc: ross.zwisler@linux.intel.com
Cc: vishal.l.verma@intel.com
Link: http://lkml.kernel.org/r/1455225857-12039-2-git-send-email-toshi.kani@hpe.com
[ Small readability edits and added object file comparison. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-02-17 09:10:22 +01:00
Heiko Carstens
52499d93d6 s390/maccess: reduce stnsm instructions
When fixing the DAT off bug ("s390: fix DAT off memory access, e.g.
on kdump") both Christian and I missed that we can save an additional
stnsm instruction.

This saves us a couple of cycles which could improve the speed of
memcpy_real.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-02-17 09:05:04 +01:00
Thomas Gleixner
8bc9162cd2 perf/x86/amd/uncore: Plug reference leak
In the error path of amd_uncore_cpu_up_prepare() the newly allocated uncore
struct is freed, but the percpu pointer still references it. Set it to NULL.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Link: http://lkml.kernel.org/r/alpine.DEB.2.11.1602162302170.19512@nanos
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-02-17 08:36:09 +01:00
Anton Protopopov
dada168b3b drm/qxl: fix erroneous return value
The qxl_gem_prime_mmap() function returns ENOSYS instead of -ENOSYS

Signed-off-by: Anton Protopopov <a.s.protopopov@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
2016-02-17 15:39:35 +10:00
Mario Kleiner
ff683df7bf drm/nouveau/display: Enable vblank irqs after display engine is on again.
In the display resume path, move the calls to drm_vblank_on()
after the point when the display engine is running again.

Since changes were made to drm_update_vblank_count() in Linux 4.4+
to emulate hw vblank counters via vblank timestamping, the function
drm_vblank_on() now needs working high precision vblank timestamping
and therefore working scanout position queries at time of call.
These don't work before the display engine gets restarted, causing
miscalculation of vblank counter increments and thereby large forward
jumps in vblank count at display resume. These jumps can cause client
hangs on resume, or desktop hangs in the case of composited desktops.

Fix this Linux 4.4 regression by reordering calls accordingly.

Signed-off-by: Mario Kleiner <mario.kleiner.de@gmail.com>
Cc: <stable@vger.kernel.org> # 4.4+
Cc: Ben Skeggs <bskeggs@redhat.com>
Cc: ville.syrjala@linux.intel.com
Cc: daniel.vetter@ffwll.ch
Cc: dri-devel@lists.freedesktop.org
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Dave Airlie <airlied@redhat.com>
2016-02-17 14:19:06 +10:00
Mario Kleiner
e0b34e3857 drm/radeon/pm: Handle failure of drm_vblank_get.
Make sure that drm_vblank_get/put() stay balanced in
case drm_vblank_get fails, by skipping the corresponding
put.

Signed-off-by: Mario Kleiner <mario.kleiner.de@gmail.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: michel@daenzer.net
Cc: dri-devel@lists.freedesktop.org
Cc: alexander.deucher@amd.com
Cc: christian.koenig@amd.com
Signed-off-by: Dave Airlie <airlied@redhat.com>
2016-02-17 14:19:03 +10:00
Mario Kleiner
bb74fc1bf3 drm: Fix treatment of drm_vblank_offdelay in drm_vblank_on() (v2)
drm_vblank_offdelay can have three different types of values:

< 0 is to be always treated the same as dev->vblank_disable_immediate
= 0 is to be treated as "never disable vblanks"
> 0 is to be treated as disable immediate if kms driver wants it
    that way via dev->vblank_disable_immediate. Otherwise it is
    a disable timeout in msecs.

This got broken in Linux 3.18+ for the implementation of
drm_vblank_on. If the user specified a value of zero which should
always reenable vblank irqs in this function, a kms driver could
override the users choice by setting vblank_disable_immediate
to true. This patch fixes the regression and keeps the user in
control.

v2: Only reenable vblank if there are clients left or the user
    requested to "never disable vblanks" via offdelay 0. Enabling
    vblanks even in the "delayed disable" case (offdelay > 0) was
    specifically added by Ville in commit cd19e52aee
    ("drm: Kick start vblank interrupts at drm_vblank_on()"),
    but after discussion it turns out that this was done by accident.

    Citing Ville: "I think it just ended up as a mess due to changing
    some of the semantics of offdelay<0 vs. offdelay==0 vs.
    disable_immediate during the review of the series. So yeah, given
    how drm_vblank_put() works now, I'd just make this check for
    offdelay==0."

Signed-off-by: Mario Kleiner <mario.kleiner.de@gmail.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>

Cc: <stable@vger.kernel.org> # 3.18+
Cc: michel@daenzer.net
Cc: vbabka@suse.cz
Cc: ville.syrjala@linux.intel.com
Cc: daniel.vetter@ffwll.ch
Cc: dri-devel@lists.freedesktop.org
Cc: alexander.deucher@amd.com
Cc: christian.koenig@amd.com
Signed-off-by: Dave Airlie <airlied@redhat.com>
2016-02-17 14:19:00 +10:00
Mario Kleiner
c61934ed9a drm: Fix drm_vblank_pre/post_modeset regression from Linux 4.4
Changes to drm_update_vblank_count() in Linux 4.4 broke the
behaviour of the pre/post modeset functions as the new update
code doesn't deal with hw vblank counter resets inbetween calls
to drm_vblank_pre_modeset an drm_vblank_post_modeset, as it
should.

This causes mistreatment of such hw counter resets as counter
wraparound, and thereby large forward jumps of the software
vblank counter which in turn cause vblank event dispatching
and vblank waits to fail/hang --> userspace clients hang.

This symptom was reported on radeon-kms to cause a infinite
hang of KDE Plasma 5 shell's login procedure, preventing users
from logging in.

Fix this by detecting when drm_update_vblank_count() is called
inside a pre->post modeset interval. If so, clamp valid vblank
increments to the safe values 0 and 1, pretty much restoring
the update behavior of the old update code of Linux 4.3 and
earlier. Also reset the last recorded hw vblank count at call
to drm_vblank_post_modeset() to be safe against hw that after
modesetting, dpms on etc. only fires its first vblank irq after
drm_vblank_post_modeset() was already called.

Reported-by: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Mario Kleiner <mario.kleiner.de@gmail.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Tested-by: Vlastimil Babka <vbabka@suse.cz>

Cc: <stable@vger.kernel.org> # 4.4+
Cc: michel@daenzer.net
Cc: vbabka@suse.cz
Cc: ville.syrjala@linux.intel.com
Cc: daniel.vetter@ffwll.ch
Cc: dri-devel@lists.freedesktop.org
Cc: alexander.deucher@amd.com
Cc: christian.koenig@amd.com
Signed-off-by: Dave Airlie <airlied@redhat.com>
2016-02-17 14:18:59 +10:00
Mario Kleiner
99b8e71597 drm: Prevent vblank counter bumps > 1 with active vblank clients. (v2)
This fixes a regression introduced by the new drm_update_vblank_count()
implementation in Linux 4.4:

Restrict the bump of the software vblank counter in drm_update_vblank_count()
to a safe maximum value of +1 whenever there is the possibility that
concurrent readers of vblank timestamps could be active at the moment,
as the current implementation of the timestamp caching and updating is
not safe against concurrent readers for calls to store_vblank() with a
bump of anything but +1. A bump != 1 would very likely return corrupted
timestamps to userspace, because the same slot in the cache could
be concurrently written by store_vblank() and read by one of those
readers in a non-atomic fashion and without the read-retry logic
detecting this collision.

Concurrent readers can exist while drm_update_vblank_count() is called
from the drm_vblank_off() or drm_vblank_on() functions or other non-vblank-
irq callers. However, all those calls are happening with the vbl_lock
locked thereby preventing a drm_vblank_get(), so the vblank refcount
can't increase while drm_update_vblank_count() is executing. Therefore
a zero vblank refcount during execution of that function signals that
is safe for arbitrary counter bumps if called from outside vblank irq,
whereas a non-zero count is not safe.

Whenever the function is called from vblank irq, we have to assume concurrent
readers could show up any time during its execution, even if the refcount
is currently zero, as vblank irqs are usually only enabled due to the
presence of readers, and because when it is called from vblank irq it
can't hold the vbl_lock to protect it from sudden bumps in vblank refcount.
Therefore also restrict bumps to +1 when the function is called from vblank
irq.

Such bumps of more than +1 can happen at other times than reenabling
vblank irqs, e.g., when regular vblank interrupts get delayed by more
than 1 frame due to long held locks, long irq off periods, realtime
preemption on RT kernels, or system management interrupts.

A better solution would be to rewrite the timestamp caching to use
full seqlocks to allow concurrent writes and reads for arbitrary
vblank counter increments.

v2: Add code comment that this is essentially a hack and should
    be replaced by a full seqlock implementation for caching of
    timestamps.

Signed-off-by: Mario Kleiner <mario.kleiner.de@gmail.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>

Cc: <stable@vger.kernel.org> # 4.4+
Cc: michel@daenzer.net
Cc: vbabka@suse.cz
Cc: ville.syrjala@linux.intel.com
Cc: daniel.vetter@ffwll.ch
Cc: dri-devel@lists.freedesktop.org
Cc: alexander.deucher@amd.com
Cc: christian.koenig@amd.com
Signed-off-by: Dave Airlie <airlied@redhat.com>
2016-02-17 14:18:59 +10:00
Mario Kleiner
e8235891b3 drm: No-Op redundant calls to drm_vblank_off() (v2)
Otherwise if a kms driver calls into drm_vblank_off() more than once
before calling drm_vblank_on() again, the redundant calls to
vblank_disable_and_save() will call drm_update_vblank_count()
while hw vblank counters and vblank timestamping are in a undefined
state during modesets, dpms off etc.

At least with the legacy drm helpers it is not unusual to
get multiple calls to drm_vblank_off and drm_vblank_on, e.g.,
half a dozen calls to drm_vblank_off and two calls to drm_vblank_on
were observed on radeon-kms during dpms-off -> dpms-on transition.

We don't no-op calls from atomic modesetting drivers, as they
should do a proper job of tracking hw state.

Fixes large jumps of the software maintained vblank counter due to
the hardware vblank counter resetting to zero during dpms off or
modeset, e.g., if radeon-kms is modified to use drm_vblank_off/on
instead of drm_vblank_pre/post_modeset().

This fixes a regression caused by the changes made to
drm_update_vblank_count() in Linux 4.4.

v2: Don't no-op on atomic modesetting drivers, per suggestion
    of Daniel Vetter.

Signed-off-by: Mario Kleiner <mario.kleiner.de@gmail.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: <stable@vger.kernel.org> # 4.4+
Cc: michel@daenzer.net
Cc: vbabka@suse.cz
Cc: ville.syrjala@linux.intel.com
Cc: alexander.deucher@amd.com
Cc: christian.koenig@amd.com
Signed-off-by: Dave Airlie <airlied@redhat.com>
2016-02-17 14:18:57 +10:00
Gerd Hoffmann
34855706c3 drm/qxl: use kmalloc_array to alloc reloc_info in qxl_process_single_command
This avoids integer overflows on 32bit machines when calculating
reloc_info size, as reported by Alan Cox.

Cc: stable@vger.kernel.org
Cc: gnomes@lxorguk.ukuu.org.uk
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Dave Airlie <airlied@redhat.com>
2016-02-17 14:16:06 +10:00
Dave Airlie
e8f051e9d8 Merge branch 'exynos-drm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/daeinki/drm-exynos into drm-fixes
Summary:
   - fix compilation warnings on ARM64bit.
   - fix mic driver initialization.
     . MIC is a part of KMS so it converts it to use component framework
       like other KMS drivers did.
   - fix wrong driver state and disable clock order on DECON driver.
   - fix incorrect use of dma_mmap_attrs function.

* 'exynos-drm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/daeinki/drm-exynos:
  drm/exynos/decon: fix disable clocks order
  drm/exynos: fix incorrect cpu address for dma_mmap_attrs()
  drm/exynos: exynos5433_decon: fix wrong state in decon_vblank_enable
  drm/exynos: exynos5433_decon: fix wrong state assignment in decon_enable
  drm/exynos: dsi: restore support for drm bridge
  drm/exynos: mic: make all functions static
  drm/exynos: mic: convert to component framework
  drm/exynos: mic: use devm_clk interface
  drm/exynos: fix types for compilation on 64bit architectures
  drm/exynos: ipp: fix incorrect format specifiers in debug messages
  drm/exynos: depend on ARCH_EXYNOS for DRM_EXYNOS
2016-02-17 14:14:22 +10:00
Dave Airlie
8ae22cb419 Revert "drm/dp/mst: change MST detection scheme"
This reverts commit cfcfa086d4.

This causes the tiling properties to break in some unexpected ways,

Revert it for now.

Cc: stable@vger.kernel.org
Signed-off-by: Dave Airlie <airlied@redhat.com>
2016-02-17 14:07:48 +10:00
Chris Mason
413eddc6ca Merge branch 'for-chris-4.5' of git://git.kernel.org/pub/scm/linux/kernel/git/fdmanana/linux into for-linus-4.5 2016-02-16 16:52:10 -08:00