It currently is required that all users of NO_SUSPEND interrupt
lines pass the IRQF_NO_SUSPEND flag when requesting the IRQ or the
WARN_ON_ONCE() in irq_pm_install_action() will trigger. That is
done to warn about situations in which unprepared interrupt handlers
may be run unnecessarily for suspended devices and may attempt to
access those devices by mistake. However, it may cause drivers
that have no technical reasons for using IRQF_NO_SUSPEND to set
that flag just because they happen to share the interrupt line
with something like a timer.
Moreover, the generic handling of wakeup interrupts introduced by
commit 9ce7a25849 (genirq: Simplify wakeup mechanism) only works
for IRQs without any NO_SUSPEND users, so the drivers of wakeup
devices needing to use shared NO_SUSPEND interrupt lines for
signaling system wakeup generally have to detect wakeup in their
interrupt handlers. Thus if they happen to share an interrupt line
with a NO_SUSPEND user, they also need to request that their
interrupt handlers be run after suspend_device_irqs().
In both cases the reason for using IRQF_NO_SUSPEND is not because
the driver in question has a genuine need to run its interrupt
handler after suspend_device_irqs(), but because it happens to
share the line with some other NO_SUSPEND user. Otherwise, the
driver would do without IRQF_NO_SUSPEND just fine.
To make it possible to specify that condition explicitly, introduce
a new IRQ action handler flag for shared IRQs, IRQF_COND_SUSPEND,
that, when set, will indicate to the IRQ core that the interrupt
user is generally fine with suspending the IRQ, but it also can
tolerate handler invocations after suspend_device_irqs() and, in
particular, it is capable of detecting system wakeup and triggering
it as appropriate from its interrupt handler.
That will allow us to work around a problem with a shared timer
interrupt line on at91 platforms.
Link: http://marc.info/?l=linux-kernel&m=142252777602084&w=2
Link: http://marc.info/?t=142252775300011&r=1&w=2
Link: https://lkml.org/lkml/2014/12/15/552
Reported-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
- minor timeout & other fixes on reservation/fence
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Merge tag 'dma-buf-for-4.0-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/sumits/dma-buf
Pull dma-buf fixes from Sumit Semwal:
"Minor timeout & other fixes on reservation/fence"
* tag 'dma-buf-for-4.0-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/sumits/dma-buf:
reservation: Remove shadowing local variable 'ret'
dma-buf/fence: don't wait when specified timeout is zero
reservation: wait only with non-zero timeout specified (v3)
DMA_BIT_MASK of 64 is not valid dma address mask for OMAPs, it should be
set to 32.
The 64 was introduced by commit (in 2009):
a152ff24b9 ASoC: OMAP: Make DMA 64 aligned
But the dma_mask and coherent_dma_mask can not be used to specify alignment.
Fixes: a152ff24b9 (ASoC: OMAP: Make DMA 64 aligned)
Reported-by: Grygorii Strashko <Grygorii.Strashko@linaro.org>
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org
- Fix for dynticks.
- Fix for smpboot bug.
- Fix for IOMMU group refcounting.
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Merge tag 'powerpc-4.0-2' of git://git.kernel.org/pub/scm/linux/kernel/git/mpe/linux
Pull powerpc fixes from Michael Ellerman:
- Fix for dynticks.
- Fix for smpboot bug.
- Fix for IOMMU group refcounting.
* tag 'powerpc-4.0-2' of git://git.kernel.org/pub/scm/linux/kernel/git/mpe/linux:
powerpc/iommu: Remove IOMMU device references via bus notifier
powerpc/smp: Wait until secondaries are active & online
powerpc: Re-enable dynticks
Report the actual error code from acpi_bus_register_driver(), it may
help future debugging (typically ENODEV as previously reported, but the
unusual cases are where it may help most).
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Acked-by: Aaron Lu <aaron.lu@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
i915.ko depends upon the acpi/video.ko module and so refuses to load if
ACPI is disabled at runtime if for example the BIOS is broken beyond
repair. acpi/video provides an optional service for i915.ko and so we
should just allow the modules to load, but do no nothing in order to let
the machines boot correctly.
Reported-by: Bill Augur <bill-auger@programmer.net>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Jani Nikula <jani.nikula@intel.com>
Cc: All applicable <stable@vger.kernel.org>
Acked-by: Aaron Lu <aaron.lu@intel.com>
[ rjw: Fixed up the new comment in acpi_video_init() ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
To keep consisitency with the rest of the file, use 'genpd' as the
name of the 'struct generic_pm_domain' pointer instead of 'gpd'.
This is just a rename, no functional changes.
Signed-off-by: Kevin Hilman <khilman@linaro.org>
Acked-by: Pavel Machek <pavel@ucw.cz>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
If CONFIG_SMP=n, <linux/smp.h> does not include <asm/smp.h>, causing:
drivers/cpufreq/ppc-corenet-cpufreq.c: In function 'corenet_cpufreq_cpu_init':
drivers/cpufreq/ppc-corenet-cpufreq.c:173:3: error: implicit declaration of function 'get_hard_smp_processor_id' [-Werror=implicit-function-declaration]
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Some BIOSes report incorrect length for ACPI address space descriptors,
so relax the checks to avoid regressions. This issue has appeared several
times as:
3162b6f0c5 ("PNPACPI: truncate _CRS windows with _LEN > _MAX - _MIN + 1")
d558b483d5 ("x86/PCI: truncate _CRS windows with _LEN > _MAX - _MIN + 1")
f238b414a7 ("PNPACPI: compute Address Space length rather than using _LEN")
48728e0774 ("x86/PCI: compute Address Space length rather than using _LEN")
Please refer to https://bugzilla.kernel.org/show_bug.cgi?id=94221
for more details and example malformed ACPI resource descriptors.
Link: https://bugzilla.kernel.org/show_bug.cgi?id=94221
Fixes: 593669c2ac (x86/PCI/ACPI: Use common ACPI resource interfaces ...)
Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Tested-by: Dave Airlie <airlied@redhat.com>
Tested-by: Prakash Punnoor <prakash@punnoor.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
When parsing resources for PCI host bridge, we should ignore resources
consumed by host bridge itself and only report window resources available
to child PCI busses.
Fixes: 593669c2ac (x86/PCI/ACPI: Use common ACPI resource interfaces ...)
Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Below are the refinements.
1. Set DMA abort bit when disabling dma channel. This will clear
the remaining data in dma FIFO, to fix channel-swap issue.
2. Read DMA HW pointer when updating DMA status. Previously dma
position is calculated by adding one period size in dma interrupt.
This is inaccurate/insufficient for some high-quality audio APP.
Since interrupt bottom half handler has variable schedule delay,
it causes big error when calculating sample delay. Read the actual
HW pointer and feedback can improve the accuracy.
3. Do some minor code clean.
Signed-off-by: Qiao Zhou <zhouqiao@marvell.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Bjørn reported that his machine hang during hibernation and eventually
bisected the problem to the following commit:
commit da2bc1b9db
Author: Imre Deak <imre.deak@intel.com>
Date: Thu Oct 23 19:23:26 2014 +0300
drm/i915: add poweroff_late handler
The problem seems to be that after the kernel puts the device into D3
the BIOS still tries to access it, or otherwise assumes that it's in D0.
This is clearly bogus, since ACPI mandates that devices are put into D3
by the OSPM if they are not wake-up sources. In the future we want to
unify more of the driver's runtime and system suspend paths, for example
by skipping all the system suspend/hibernation hooks if the device is
runtime suspended already. Accordingly for all other platforms the goal
is still to properly power down the device during hibernation.
v2:
- Another GEN4 Lenovo laptop had the same issue, while platforms from
other vendors (including mobile and desktop, GEN4 and non-GEN4) seem
to work fine. Based on this apply the workaround on all GEN4 Lenovo
platforms.
- add code comment about failing platforms (Ville)
Reference: http://lists.freedesktop.org/archives/intel-gfx/2015-February/060633.html
Reported-and-bisected-by: Bjørn Mork <bjorn@mork.no>
Cc: stable@vger.kernel.org # v3.19
Signed-off-by: Imre Deak <imre.deak@intel.com>
Acked-by: Daniel Vetter <daniel.vetter@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
When we takeover from the BIOS and install our interrupt handler, the
BIOS may have left us a few surprises in the form of spontaneous
interrupts. (This is especially likely on hardware like 965gm where
display fifo underruns are continuous and the GMCH cannot filter that
interrupt souce.) As we enable our IRQ early so that we can use it
during hardware probing, our interrupt handler must be prepared to
handle a few sources prior to being fully configured. As such, we need
to add a simple is-ready check prior to dereferencing our KMS state for
reporting underruns.
Reported-by: Rob Clark <rclark@redhat.com>
Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1193972
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: stable@vger.kernel.org
[Jani: dropped the extra !]
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
If the call to exchange-id returns with the EXCHGID4_FLAG_CONFIRMED_R flag
set, then that means our lease was established by a previous mount instance.
Ensure that we detect this situation, and that we clear the state held by
that mount.
Reported-by: Jorge Mora <Jorge.Mora@netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
After d905c5df9a ("PPC: POWERNV: move iommu_add_device earlier"), the
refcnt on the kobject backing the IOMMU group for a PCI device is
elevated by each call to pci_dma_dev_setup_pSeriesLP() (via
set_iommu_table_base_and_group). When we go to dlpar a multi-function
PCI device out:
iommu_reconfig_notifier ->
iommu_free_table ->
iommu_group_put
BUG_ON(tbl->it_group)
We trip this BUG_ON, because there are still references on the table, so
it is not freed. Fix this by moving the powernv bus notifier to common
code and calling it for both powernv and pseries.
Fixes: d905c5df9a ("PPC: POWERNV: move iommu_add_device earlier")
Signed-off-by: Nishanth Aravamudan <nacc@linux.vnet.ibm.com>
Tested-by: Nishanth Aravamudan <nacc@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Anton has a busy ppc64le KVM box where guests sometimes hit the infamous
"kernel BUG at kernel/smpboot.c:134!" issue during boot:
BUG_ON(td->cpu != smp_processor_id());
Basically a per CPU hotplug thread scheduled on the wrong CPU. The oops
output confirms it:
CPU: 0
Comm: watchdog/130
The problem is that we aren't ensuring the CPU active bit is set for the
secondary before allowing the master to continue on. The master unparks
the secondary CPU's kthreads and the scheduler looks for a CPU to run
on. It calls select_task_rq() and realises the suggested CPU is not in
the cpus_allowed mask. It then ends up in select_fallback_rq(), and
since the active bit isnt't set we choose some other CPU to run on.
This seems to have been introduced by 6acbfb9697 "sched: Fix hotplug
vs. set_cpus_allowed_ptr()", which changed from setting active before
online to setting active after online. However that was in turn fixing a
bug where other code assumed an active CPU was also online, so we can't
just revert that fix.
The simplest fix is just to spin waiting for both active & online to be
set. We already have a barrier prior to set_cpu_online() (which also
sets active), to ensure all other setup is completed before online &
active are set.
Fixes: 6acbfb9697 ("sched: Fix hotplug vs. set_cpus_allowed_ptr()")
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
We do not want to allow a race with another NFS mount to cause
nfs41_walk_client_list() to establish a lease on our nfs_client before
we're done checking for trunking.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Pull nfsd fixes from Bruce Fields:
"Three miscellaneous bugfixes, most importantly the clp->cl_revoked
bug, which we've seen several reports of people hitting"
* 'for-4.0' of git://linux-nfs.org/~bfields/linux:
sunrpc: integer underflow in rsc_parse()
nfsd: fix clp->cl_revoked list deletion causing softlock in nfsd
svcrpc: fix memory leak in gssp_accept_sec_context_upcall
Pull networking fixes from David Miller:
1) If an IPVS tunnel is created with a mixed-family destination
address, it cannot be removed. Fix from Alexey Andriyanov.
2) Fix module refcount underflow in netfilter's nft_compat, from Pablo
Neira Ayuso.
3) Generic statistics infrastructure can reference variables sitting on
a released function stack, therefore use dynamic allocation always.
Fix from Ignacy Gawędzki.
4) skb_copy_bits() return value test is inverted in ip_check_defrag().
5) Fix network namespace exit in openvswitch, we have to release all of
the per-net vports. From Pravin B Shelar.
6) Fix signedness bug in CAIF's cfpkt_iterate(), from Dan Carpenter.
7) Fix rhashtable grow/shrink behavior, only expand during inserts and
shrink during deletes. From Daniel Borkmann.
8) Netdevice names with semicolons should never be allowed, because
they serve as a separator. From Matthew Thode.
9) Use {,__}set_current_state() where appropriate, from Fabian
Frederick.
10) Revert byte queue limits support in r8169 driver, it's causing
regressions we can't figure out.
11) tcp_should_expand_sndbuf() erroneously uses tp->packets_out to
measure packets in flight, properly use tcp_packets_in_flight()
instead. From Neal Cardwell.
12) Fix accidental removal of support for bluetooth in CSR based Intel
wireless cards. From Marcel Holtmann.
13) We accidently added a behavioral change between native and compat
tasks, wrt testing the MSG_CMSG_COMPAT bit. Just ignore it if the
user happened to set it in a native binary as that was always the
behavior we had. From Catalin Marinas.
14) Check genlmsg_unicast() return valud in hwsim netlink tx frame
handling, from Bob Copeland.
15) Fix stale ->radar_required setting in mac80211 that can prevent
starting new scans, from Eliad Peller.
16) Fix memory leak in nl80211 monitor, from Johannes Berg.
17) Fix race in TX index handling in xen-netback, from David Vrabel.
18) Don't enable interrupts in amx-xgbe driver until all software et al.
state is ready for the interrupt handler to run. From Thomas
Lendacky.
19) Add missing netlink_ns_capable() checks to rtnl_newlink(), from Eric
W Biederman.
20) The amount of header space needed in macvtap was not calculated
properly, fix it otherwise we splat past the beginning of the
packet. From Eric Dumazet.
21) Fix bcmgenet TCP TX perf regression, from Jaedon Shin.
22) Don't raw initialize or mod timers, use setup_timer() and
mod_timer() instead. From Vaishali Thakkar.
23) Fix software maintained statistics in bcmgenet and systemport
drivers, from Florian Fainelli.
24) DMA descriptor updates in sh_eth need proper memory barriers, from
Ben Hutchings.
25) Don't do UDP Fragmentation Offload on RAW sockets, from Michal
Kubecek.
26) Openvswitch's non-masked set actions aren't constructed properly
into netlink messages, fix from Joe Stringer.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (116 commits)
openvswitch: Fix serialization of non-masked set actions.
gianfar: Reduce logging noise seen due to phy polling if link is down
ibmveth: Add function to enable live MAC address changes
net: bridge: add compile-time assert for cb struct size
udp: only allow UFO for packets from SOCK_DGRAM sockets
sh_eth: Really fix padding of short frames on TX
Revert "sh_eth: Enable Rx descriptor word 0 shift for r8a7790"
sh_eth: Fix RX recovery on R-Car in case of RX ring underrun
sh_eth: Ensure proper ordering of descriptor active bit write/read
net/mlx4_en: Disbale GRO for incoming loopback/selftest packets
net/mlx4_core: Fix wrong mask and error flow for the update-qp command
net: systemport: fix software maintained statistics
net: bcmgenet: fix software maintained statistics
rxrpc: don't multiply with HZ twice
rxrpc: terminate retrans loop when sending of skb fails
net/hsr: Fix NULL pointer dereference and refcnt bugs when deleting a HSR interface.
net: pasemi: Use setup_timer and mod_timer
net: stmmac: Use setup_timer and mod_timer
net: 8390: axnet_cs: Use setup_timer and mod_timer
net: 8390: pcnet_cs: Use setup_timer and mod_timer
...
Split DCE6 and DCE8 programming of DCCG_AUDIO_DTO1
registers to properly enable DP audio for both DCE
revisions.
Signed-off-by: Slava Grigorev <slava.grigorev@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
- Move it out of the UNIPHY case to handle older DCE blocks.
- set audio dpms before video dpms
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
We don't necessarily have an EDID at this point when
audio detect gets called. Ideally we'd update these
fields in detect, but that requires a larger rework
of the display detect code.
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Set actions consist of a regular OVS_KEY_ATTR_* attribute nested inside
of a OVS_ACTION_ATTR_SET action attribute. When converting masked actions
back to regular set actions, the inner attribute length was not changed,
ie, double the length being serialized. This patch fixes the bug.
Fixes: 83d2b9b ("net: openvswitch: Support masked set actions.")
Signed-off-by: Joe Stringer <joestringer@nicira.com>
Acked-by: Jarno Rajahalme <jrajahalme@nicira.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Commit 6ce29b0e2a ("gianfar: Avoid unnecessary reg accesses in adjust_link()")
eliminates unnecessary calls to adjust_link for phy devices which don't support
interrupts and need polling. As part of that work, the 'new_state' local flag,
which was used to reduce logging noise on the console, was eliminated.
Unfortunately, that means that a 'Link is Down' log message will now be
issued continuously if a link is configured as UP, the link state is down,
and the associated phy requires polling. This occurs because priv->oldduplex
is -1 in this case, which always differs from phydev->duplex. In addition,
phydev->speed may also differ from priv->oldspeed. gfar_update_link_state()
is therefore called each time a phy is polled, even if the link state did not
change.
Cc: Claudiu Manoil <claudiu.manoil@freescale.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Claudiu Manoil <claudiu.manoil@freescale.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add a function that will enable changing the MAC address
of an ibmveth interface while it is still running.
Signed-off-by: Thomas Falcon <tlfalcon@linux.vnet.ibm.com>
Reviewed-by: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: David S. Miller <davem@davemloft.net>
make build fail if structure no longer fits into ->cb storage.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
nfs_vm_page_mkwrite() should wait until the page cache invalidation
is finished. This is the second patch in a 2 patch series to deprecate
the NFS client's reliance on nfs_release_page() in the context of
nfs_invalidate_mapping().
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
When invalidating the page cache for a regular file, we want to first
sync all dirty data to disk and then call invalidate_inode_pages2().
The latter relies on nfs_launder_page() and nfs_release_page() to deal
respectively with dirty pages, and unstable written pages.
When commit 9590544694 ("NFS: avoid deadlocks with loop-back mounted
NFS filesystems.") changed the behaviour of nfs_release_page(), then it
made it possible for invalidate_inode_pages2() to fail with an EBUSY.
Unfortunately, that error is then propagated back to read().
Let's therefore work around the problem for now by protecting the call
to sync the data and invalidate_inode_pages2() so that they are atomic
w.r.t. the addition of new writes.
Later on, we can revisit whether or not we still need nfs_launder_page()
and nfs_release_page().
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
This is a tricky story of the new atomic state handling and the legacy
code fighting over each another. The bug at hand is an underrun of the
framebuffer reference with subsequent hilarity caused by the load
detect code. Which is peculiar since the the exact same code works
fine as the implementation of the legacy setcrtc ioctl.
Let's look at the ingredients:
- Currently our code is a crazy mix of legacy modeset interfaces to
set the parameters and half-baked atomic state tracking underneath.
While this transition is going we're using the transitional plane
helpers to update the atomic side (drm_plane_helper_disable/update
and friends), i.e. plane->state->fb. Since the state structure owns
the fb those functions take care of that themselves.
The legacy state (specifically crtc->primary->fb) is still managed
by the old code (and mostly by the drm core), with the fb reference
counting done by callers (core drm for the ioctl or the i915 load
detect code). The relevant commit is
commit ea2c67bb4a
Author: Matt Roper <matthew.d.roper@intel.com>
Date: Tue Dec 23 10:41:52 2014 -0800
drm/i915: Move to atomic plane helpers (v9)
- drm_plane_helper_disable has special code to handle multiple calls
in a row - it checks plane->crtc == NULL and bails out. This is to
match the proper atomic implementation which needs the crtc to get
at the implied locking context atomic updates always need. See
commit acf24a395c
Author: Daniel Vetter <daniel.vetter@ffwll.ch>
Date: Tue Jul 29 15:33:05 2014 +0200
drm/plane-helper: transitional atomic plane helpers
- The universal plane code split out the implicit primary plane from
the CRTC into it's own full-blown drm_plane object. As part of that
the setcrtc ioctl (which updated both the crtc mode and primary
plane) learned to set crtc->primary->crtc on modeset to make sure
the plane->crtc assignments statate up to date in
commit e13161af80
Author: Matt Roper <matthew.d.roper@intel.com>
Date: Tue Apr 1 15:22:38 2014 -0700
drm: Add drm_crtc_init_with_planes() (v2)
Unfortunately we've forgotten to update the load detect code. Which
wasn't a problem since the load detect modeset is temporary and
always undone before we drop the locks.
- Finally there is a organically grown history (i.e. don't ask) around
who sets the legacy plane->fb for the various driver entry points.
Originally updating that was the drivers duty, but for almost all
places we've moved that (plus updating the refcounts) into the core.
Again the exception is the load detect code.
Taking all together the following happens:
- The load detect code doesn't set crtc->primary->crtc. This is only
really an issue on crtcs never before used or when userspace
explicitly disabled the primary plane.
- The plane helper glue code short-circuits because of that and leaves
a non-NULL fb behind in plane->state->fb and plane->fb. The state
fb isn't a real problem (it's properly refcounted on its own), it's
just the canary.
- Load detect code drops the reference for that fb, but doesn't set
plane->fb = NULL. This is ok since it's still living in that old
world where drivers had to clear the pointer but the core/callers
handled the refcounting.
- On the next modeset the drm core notices plane->fb and takes care of
refcounting it properly by doing another unref. This drops the
refcount to zero, leaving state->plane now pointing at freed memory.
- intel_plane_duplicate_state still assume it owns a reference to that
very state->fb and bad things start to happen.
Fix this all by applying the same duct-tape as for the legacy setcrtc
ioctl code and set crtc->primary->crtc properly.
Cc: Matt Roper <matthew.d.roper@intel.com>
Cc: Paul Bolle <pebolle@tiscali.nl>
Cc: Rob Clark <robdclark@gmail.com>
Cc: Paulo Zanoni <przanoni@gmail.com>
Cc: Sean Paul <seanpaul@chromium.org>
Cc: Matt Roper <matthew.d.roper@intel.com>
Reported-and-tested-by: Linus Torvalds <torvalds@linux-foundation.org>
Reported-by: Paul Bolle <pebolle@tiscali.nl>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The plane allocator has been inherently racy since the beginning of the
transition to atomic updates, as the allocator lock is released between
free plane check (at .atomic_check() time) and the reservation (at
.atomic_update() time).
To fix it, create a new allocator solely based on the atomic plane
states without keeping any external state and perform allocation in the
.atomic_check() handler. The core idea is to replace the free planes
bitmask with a collective knowledge based on the allocated hardware
plane(s) for each KMS plane. The allocator then loops over all plane
states to compute the free planes bitmask, allocates hardware planes
based on that bitmask, and stores the result back in the plane states.
For this to work we need to access the current state of planes not
touched by the atomic update. To ensure that it won't be modified, we
need to lock all planes using drm_atomic_get_plane_state(). This
effectively serializes atomic updates from .atomic_check() up to
completion, either when swapping the states if the check step has
succeeded, or when freeing the states if the check step has failed.
Suggested-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Mark Brown