<feed xmlns='http://www.w3.org/2005/Atom'>
<title>kernel/linux.git/drivers/gpu/drm/v3d, branch v6.12.22</title>
<subtitle>Linux kernel stable tree (mirror)</subtitle>
<id>https://git.radix-linux.su/kernel/linux.git/atom?h=v6.12.22</id>
<link rel='self' href='https://git.radix-linux.su/kernel/linux.git/atom?h=v6.12.22'/>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/'/>
<updated>2025-03-28T21:03:29+00:00</updated>
<entry>
<title>drm/v3d: Don't run jobs that have errors flagged in its fence</title>
<updated>2025-03-28T21:03:29+00:00</updated>
<author>
<name>Maíra Canal</name>
<email>mcanal@igalia.com</email>
</author>
<published>2025-03-13T14:43:26+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=4b4d2527840f088a8df19027a6c208f4122a7106'/>
<id>urn:sha1:4b4d2527840f088a8df19027a6c208f4122a7106</id>
<content type='text'>
commit 80cbee810e4e13cdbd3ae9654e9ecddf17f3e828 upstream.

The V3D driver still relies on `drm_sched_increase_karma()` and
`drm_sched_resubmit_jobs()` for resubmissions when a timeout occurs.
The function `drm_sched_increase_karma()` marks the job as guilty, while
`drm_sched_resubmit_jobs()` sets an error (-ECANCELED) in the DMA fence of
that guilty job.

Because of this, we must check whether the job’s DMA fence has been
flagged with an error before executing the job. Otherwise, the same guilty
job may be resubmitted indefinitely, causing repeated GPU resets.

This patch adds a check for an error on the job's fence to prevent running
a guilty job that was previously flagged when the GPU timed out.

Note that the CPU and CACHE_CLEAN queues do not require this check, as
their jobs are executed synchronously once the DRM scheduler starts them.

Cc: stable@vger.kernel.org
Fixes: d223f98f0209 ("drm/v3d: Add support for compute shader dispatch.")
Fixes: 1584f16ca96e ("drm/v3d: Add support for submitting jobs to the TFU.")
Reviewed-by: Iago Toral Quiroga &lt;itoral@igalia.com&gt;
Signed-off-by: Maíra Canal &lt;mcanal@igalia.com&gt;
Link: https://patchwork.freedesktop.org/patch/msgid/20250313-v3d-gpu-reset-fixes-v4-1-c1e780d8e096@igalia.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>drm/v3d: Stop active perfmon if it is being destroyed</title>
<updated>2025-02-21T13:01:45+00:00</updated>
<author>
<name>Christian Gmeiner</name>
<email>cgmeiner@igalia.com</email>
</author>
<published>2024-11-18T22:19:47+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=1c5673a2c8926adbb61f340c779b28e18188a8cd'/>
<id>urn:sha1:1c5673a2c8926adbb61f340c779b28e18188a8cd</id>
<content type='text'>
commit 21f1435b1e6b012a07c42f36b206d2b66fc8f13b upstream.

If the active performance monitor (`v3d-&gt;active_perfmon`) is being
destroyed, stop it first. Currently, the active perfmon is not
stopped during destruction, leaving the `v3d-&gt;active_perfmon` pointer
stale. This can lead to undefined behavior and instability.

This patch ensures that the active perfmon is stopped before being
destroyed, aligning with the behavior introduced in commit
7d1fd3638ee3 ("drm/v3d: Stop the active perfmon before being destroyed").

Cc: stable@vger.kernel.org # v5.15+
Fixes: 26a4dc29b74a ("drm/v3d: Expose performance counters to userspace")
Signed-off-by: Christian Gmeiner &lt;cgmeiner@igalia.com&gt;
Signed-off-by: Maíra Canal &lt;mcanal@igalia.com&gt;
Link: https://patchwork.freedesktop.org/patch/msgid/20241118221948.1758130-1-christian.gmeiner@gmail.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>drm/v3d: Fix performance counter source settings on V3D 7.x</title>
<updated>2025-02-08T08:56:55+00:00</updated>
<author>
<name>Maíra Canal</name>
<email>mcanal@igalia.com</email>
</author>
<published>2024-11-06T12:16:51+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=af8d1d524ba635dae32108de395db92970dc2bf9'/>
<id>urn:sha1:af8d1d524ba635dae32108de395db92970dc2bf9</id>
<content type='text'>
[ Upstream commit e987e22e9229d70c2083a91cc61269b2c4924955 ]

When the new register addresses were introduced for V3D 7.x, we added
new masks for performance counter sources on V3D 7.x.  Nevertheless,
we never apply these new masks when setting the sources.

Fix the performance counter source settings on V3D 7.x by introducing
a new macro, `V3D_SET_FIELD_VER`, which allows fields setting to vary
by version. Using this macro, we can provide different values for
source mask based on the V3D version, ensuring that sources are
correctly configure on V3D 7.x.

Fixes: 0ad5bc1ce463 ("drm/v3d: fix up register addresses for V3D 7.x")
Signed-off-by: Maíra Canal &lt;mcanal@igalia.com&gt;
Reviewed-by: Iago Toral Quiroga &lt;itoral@igalia.com&gt;
Reviewed-by: Christian Gmeiner &lt;cgmeiner@igalia.com&gt;
Link: https://patchwork.freedesktop.org/patch/msgid/20241106121736.5707-1-mcanal@igalia.com
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>drm/v3d: Assign job pointer to NULL before signaling the fence</title>
<updated>2025-02-01T17:39:40+00:00</updated>
<author>
<name>Maíra Canal</name>
<email>mcanal@igalia.com</email>
</author>
<published>2025-01-23T01:24:03+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=01a7e3a43ee2e6607169a75889412344c10b37fd'/>
<id>urn:sha1:01a7e3a43ee2e6607169a75889412344c10b37fd</id>
<content type='text'>
commit 6e64d6b3a3c39655de56682ec83e894978d23412 upstream.

In commit e4b5ccd392b9 ("drm/v3d: Ensure job pointer is set to NULL
after job completion"), we introduced a change to assign the job pointer
to NULL after completing a job, indicating job completion.

However, this approach created a race condition between the DRM
scheduler workqueue and the IRQ execution thread. As soon as the fence is
signaled in the IRQ execution thread, a new job starts to be executed.
This results in a race condition where the IRQ execution thread sets the
job pointer to NULL simultaneously as the `run_job()` function assigns
a new job to the pointer.

This race condition can lead to a NULL pointer dereference if the IRQ
execution thread sets the job pointer to NULL after `run_job()` assigns
it to the new job. When the new job completes and the GPU emits an
interrupt, `v3d_irq()` is triggered, potentially causing a crash.

[  466.310099] Unable to handle kernel NULL pointer dereference at virtual address 00000000000000c0
[  466.318928] Mem abort info:
[  466.321723]   ESR = 0x0000000096000005
[  466.325479]   EC = 0x25: DABT (current EL), IL = 32 bits
[  466.330807]   SET = 0, FnV = 0
[  466.333864]   EA = 0, S1PTW = 0
[  466.337010]   FSC = 0x05: level 1 translation fault
[  466.341900] Data abort info:
[  466.344783]   ISV = 0, ISS = 0x00000005, ISS2 = 0x00000000
[  466.350285]   CM = 0, WnR = 0, TnD = 0, TagAccess = 0
[  466.355350]   GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0
[  466.360677] user pgtable: 4k pages, 39-bit VAs, pgdp=0000000089772000
[  466.367140] [00000000000000c0] pgd=0000000000000000, p4d=0000000000000000, pud=0000000000000000
[  466.375875] Internal error: Oops: 0000000096000005 [#1] PREEMPT SMP
[  466.382163] Modules linked in: rfcomm snd_seq_dummy snd_hrtimer snd_seq snd_seq_device algif_hash algif_skcipher af_alg bnep binfmt_misc vc4 snd_soc_hdmi_codec drm_display_helper cec brcmfmac_wcc spidev rpivid_hevc(C) drm_client_lib brcmfmac hci_uart drm_dma_helper pisp_be btbcm brcmutil snd_soc_core aes_ce_blk v4l2_mem2mem bluetooth aes_ce_cipher snd_compress videobuf2_dma_contig ghash_ce cfg80211 gf128mul snd_pcm_dmaengine videobuf2_memops ecdh_generic sha2_ce ecc videobuf2_v4l2 snd_pcm v3d sha256_arm64 rfkill videodev snd_timer sha1_ce libaes gpu_sched snd videobuf2_common sha1_generic drm_shmem_helper mc rp1_pio drm_kms_helper raspberrypi_hwmon spi_bcm2835 gpio_keys i2c_brcmstb rp1 raspberrypi_gpiomem rp1_mailbox rp1_adc nvmem_rmem uio_pdrv_genirq uio i2c_dev drm ledtrig_pattern drm_panel_orientation_quirks backlight fuse dm_mod ip_tables x_tables ipv6
[  466.458429] CPU: 0 UID: 1000 PID: 2008 Comm: chromium Tainted: G         C         6.13.0-v8+ #18
[  466.467336] Tainted: [C]=CRAP
[  466.470306] Hardware name: Raspberry Pi 5 Model B Rev 1.0 (DT)
[  466.476157] pstate: 404000c9 (nZcv daIF +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[  466.483143] pc : v3d_irq+0x118/0x2e0 [v3d]
[  466.487258] lr : __handle_irq_event_percpu+0x60/0x228
[  466.492327] sp : ffffffc080003ea0
[  466.495646] x29: ffffffc080003ea0 x28: ffffff80c0c94200 x27: 0000000000000000
[  466.502807] x26: ffffffd08dd81d7b x25: ffffff80c0c94200 x24: ffffff8003bdc200
[  466.509969] x23: 0000000000000001 x22: 00000000000000a7 x21: 0000000000000000
[  466.517130] x20: ffffff8041bb0000 x19: 0000000000000001 x18: 0000000000000000
[  466.524291] x17: ffffffafadfb0000 x16: ffffffc080000000 x15: 0000000000000000
[  466.531452] x14: 0000000000000000 x13: 0000000000000000 x12: 0000000000000000
[  466.538613] x11: 0000000000000000 x10: 0000000000000000 x9 : ffffffd08c527eb0
[  466.545777] x8 : 0000000000000000 x7 : 0000000000000000 x6 : 0000000000000000
[  466.552941] x5 : ffffffd08c4100d0 x4 : ffffffafadfb0000 x3 : ffffffc080003f70
[  466.560102] x2 : ffffffc0829e8058 x1 : 0000000000000001 x0 : 0000000000000000
[  466.567263] Call trace:
[  466.569711]  v3d_irq+0x118/0x2e0 [v3d] (P)
[  466.573826]  __handle_irq_event_percpu+0x60/0x228
[  466.578546]  handle_irq_event+0x54/0xb8
[  466.582391]  handle_fasteoi_irq+0xac/0x240
[  466.586498]  generic_handle_domain_irq+0x34/0x58
[  466.591128]  gic_handle_irq+0x48/0xd8
[  466.594798]  call_on_irq_stack+0x24/0x58
[  466.598730]  do_interrupt_handler+0x88/0x98
[  466.602923]  el0_interrupt+0x44/0xc0
[  466.606508]  __el0_irq_handler_common+0x18/0x28
[  466.611050]  el0t_64_irq_handler+0x10/0x20
[  466.615156]  el0t_64_irq+0x198/0x1a0
[  466.618740] Code: 52800035 3607faf3 f9442e80 52800021 (f9406018)
[  466.624853] ---[ end trace 0000000000000000 ]---
[  466.629483] Kernel panic - not syncing: Oops: Fatal exception in interrupt
[  466.636384] SMP: stopping secondary CPUs
[  466.640320] Kernel Offset: 0x100c400000 from 0xffffffc080000000
[  466.646259] PHYS_OFFSET: 0x0
[  466.649141] CPU features: 0x100,00000170,00901250,0200720b
[  466.654644] Memory Limit: none
[  466.657706] ---[ end Kernel panic - not syncing: Oops: Fatal exception in interrupt ]---

Fix the crash by assigning the job pointer to NULL before signaling the
fence. This ensures that the job pointer is cleared before any new job
starts execution, preventing the race condition and the NULL pointer
dereference crash.

Cc: stable@vger.kernel.org
Fixes: e4b5ccd392b9 ("drm/v3d: Ensure job pointer is set to NULL after job completion")
Signed-off-by: Maíra Canal &lt;mcanal@igalia.com&gt;
Reviewed-by: Jose Maria Casanova Crespo &lt;jmcasanova@igalia.com&gt;
Reviewed-by: Iago Toral Quiroga &lt;itoral@igalia.com&gt;
Tested-by: Phil Elwell &lt;phil@raspberrypi.com&gt;
Link: https://patchwork.freedesktop.org/patch/msgid/20250123012403.20447-1-mcanal@igalia.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>drm/v3d: Ensure job pointer is set to NULL after job completion</title>
<updated>2025-01-23T16:22:52+00:00</updated>
<author>
<name>Maíra Canal</name>
<email>mcanal@igalia.com</email>
</author>
<published>2025-01-13T15:47:40+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=b22467b1ae104073dcb11aa78562a331cd7fb0e0'/>
<id>urn:sha1:b22467b1ae104073dcb11aa78562a331cd7fb0e0</id>
<content type='text'>
[ Upstream commit e4b5ccd392b92300a2b341705cc4805681094e49 ]

After a job completes, the corresponding pointer in the device must
be set to NULL. Failing to do so triggers a warning when unloading
the driver, as it appears the job is still active. To prevent this,
assign the job pointer to NULL after completing the job, indicating
the job has finished.

Fixes: 14d1d1908696 ("drm/v3d: Remove the bad signaled() implementation.")
Signed-off-by: Maíra Canal &lt;mcanal@igalia.com&gt;
Reviewed-by: Jose Maria Casanova Crespo &lt;jmcasanova@igalia.com&gt;
Link: https://patchwork.freedesktop.org/patch/msgid/20250113154741.67520-1-mcanal@igalia.com
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>drm/v3d: Enable Performance Counters before clearing them</title>
<updated>2024-12-14T19:03:18+00:00</updated>
<author>
<name>Maíra Canal</name>
<email>mcanal@igalia.com</email>
</author>
<published>2024-12-04T12:28:31+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=b94c2f7a1a238c7c4e430671bf25b75ed96e430a'/>
<id>urn:sha1:b94c2f7a1a238c7c4e430671bf25b75ed96e430a</id>
<content type='text'>
[ Upstream commit c98b10496b2f3c4f576af3482c71aadcfcbf765e ]

On the Raspberry Pi 5, performance counters are not being cleared
when `v3d_perfmon_start()` is called, even though we write to the
CLR register. As a result, their values accumulate until they
overflow.

The expected behavior is for performance counters to reset to zero
at the start of a job. When the job finishes and the perfmon is
stopped, the counters should accurately reflect the values for that
specific job.

To ensure this behavior, the performance counters are now enabled
before being cleared. This allows the CLR register to function as
intended, zeroing the counter values when the job begins.

Fixes: 26a4dc29b74a ("drm/v3d: Expose performance counters to userspace")
Signed-off-by: Maíra Canal &lt;mcanal@igalia.com&gt;
Reviewed-by: Iago Toral Quiroga &lt;itoral@igalia.com&gt;
Link: https://patchwork.freedesktop.org/patch/msgid/20241204122831.17015-1-mcanal@igalia.com
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>drm/v3d: Flush the MMU before we supply more memory to the binner</title>
<updated>2024-12-05T13:01:38+00:00</updated>
<author>
<name>Maíra Canal</name>
<email>mcanal@igalia.com</email>
</author>
<published>2024-09-23T13:55:06+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=86ab3d85b227b60eef14fd4a90b7a0be6573118a'/>
<id>urn:sha1:86ab3d85b227b60eef14fd4a90b7a0be6573118a</id>
<content type='text'>
[ Upstream commit d2fb8811108b2c1285c56f4fba4fff8fe3525593 ]

We must ensure that the MMU is flushed before we supply more memory to
the binner, otherwise we might end up with invalid MMU accesses by the
GPU.

Fixes: 57692c94dcbe ("drm/v3d: Introduce a new DRM driver for Broadcom V3D V3.x+")
Signed-off-by: Maíra Canal &lt;mcanal@igalia.com&gt;
Reviewed-by: Iago Toral Quiroga &lt;itoral@igalia.com&gt;
Link: https://patchwork.freedesktop.org/patch/msgid/20240923141348.2422499-3-mcanal@igalia.com
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>drm/v3d: Address race-condition in MMU flush</title>
<updated>2024-12-05T13:01:38+00:00</updated>
<author>
<name>Maíra Canal</name>
<email>mcanal@igalia.com</email>
</author>
<published>2024-09-23T13:55:05+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=482ac8a1c87fad12d30a54afc26d9f25610595cd'/>
<id>urn:sha1:482ac8a1c87fad12d30a54afc26d9f25610595cd</id>
<content type='text'>
[ Upstream commit cf1becb7f996a0a23ea2c270cf6bb0911ec3ca1a ]

We must first flush the MMU cache and then, flush the TLB, not the other
way around. Currently, we can see a race condition between the MMU cache
and the TLB when running multiple rendering processes at the same time.
This is evidenced by MMU errors triggered by the IRQ.

Fix the MMU flush order by flushing the MMU cache and then the TLB.
Also, in order to address the race condition, wait for the MMU cache flush
to finish before starting the TLB flush.

Fixes: 57692c94dcbe ("drm/v3d: Introduce a new DRM driver for Broadcom V3D V3.x+")
Signed-off-by: Maíra Canal &lt;mcanal@igalia.com&gt;
Reviewed-by: Iago Toral Quiroga &lt;itoral@igalia.com&gt;
Link: https://patchwork.freedesktop.org/patch/msgid/20240923141348.2422499-2-mcanal@igalia.com
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>drm/v3d: Appease lockdep while updating GPU stats</title>
<updated>2024-12-05T13:01:37+00:00</updated>
<author>
<name>Tvrtko Ursulin</name>
<email>tvrtko.ursulin@igalia.com</email>
</author>
<published>2024-08-13T10:25:05+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=ec6de20f2e7e899b1c2a5af187f742f263f49093'/>
<id>urn:sha1:ec6de20f2e7e899b1c2a5af187f742f263f49093</id>
<content type='text'>
[ Upstream commit 06c3c406850e5495bb56ccf624d0c9477e1ba901 ]

Lockdep thinks our seqcount_t usage is unsafe because the update path can
be both from irq and worker context:

 [ ] ================================
 [ ] WARNING: inconsistent lock state
 [ ] 6.10.3-v8-16k-numa #159 Tainted: G        WC
 [ ] --------------------------------
 [ ] inconsistent {HARDIRQ-ON-W} -&gt; {IN-HARDIRQ-W} usage.
 [ ] swapper/0/0 [HC1[1]:SC0[0]:HE0:SE1] takes:
 [ ] ffff80003d7c08d0 (&amp;v3d_priv-&gt;stats[i].lock){?.+.}-{0:0}, at: v3d_irq+0xc8/0x660 [v3d]
 [ ] {HARDIRQ-ON-W} state was registered at:
 [ ]   lock_acquire+0x1f8/0x328
 [ ]   v3d_job_start_stats.isra.0+0xd8/0x218 [v3d]
 [ ]   v3d_bin_job_run+0x23c/0x388 [v3d]
 [ ]   drm_sched_run_job_work+0x520/0x6d0 [gpu_sched]
 [ ]   process_one_work+0x62c/0xb48
 [ ]   worker_thread+0x468/0x5b0
 [ ]   kthread+0x1c4/0x1e0
 [ ]   ret_from_fork+0x10/0x20
 [ ] irq event stamp: 337094
 [ ] hardirqs last  enabled at (337093): [&lt;ffffc0008144ce7c&gt;] default_idle_call+0x11c/0x140
 [ ] hardirqs last disabled at (337094): [&lt;ffffc0008144a354&gt;] el1_interrupt+0x24/0x58
 [ ] softirqs last  enabled at (337082): [&lt;ffffc00080061d90&gt;] handle_softirqs+0x4e0/0x538
 [ ] softirqs last disabled at (337073): [&lt;ffffc00080010364&gt;] __do_softirq+0x1c/0x28
 [ ]
                other info that might help us debug this:
 [ ]  Possible unsafe locking scenario:

 [ ]        CPU0
 [ ]        ----
 [ ]   lock(&amp;v3d_priv-&gt;stats[i].lock);
 [ ]   &lt;Interrupt&gt;
 [ ]     lock(&amp;v3d_priv-&gt;stats[i].lock);
 [ ]
                *** DEADLOCK ***

 [ ] no locks held by swapper/0/0.
 [ ]
               stack backtrace:
 [ ] CPU: 0 PID: 0 Comm: swapper/0 Tainted: G        WC         6.10.3-v8-16k-numa #159
 [ ] Hardware name: Raspberry Pi 5 Model B Rev 1.0 (DT)
 [ ] Call trace:
 [ ]  dump_backtrace+0x170/0x1b8
 [ ]  show_stack+0x20/0x38
 [ ]  dump_stack_lvl+0xb4/0xd0
 [ ]  dump_stack+0x18/0x28
 [ ]  print_usage_bug+0x3cc/0x3f0
 [ ]  mark_lock+0x4d0/0x968
 [ ]  __lock_acquire+0x784/0x18c8
 [ ]  lock_acquire+0x1f8/0x328
 [ ]  v3d_job_update_stats+0xec/0x2e0 [v3d]
 [ ]  v3d_irq+0xc8/0x660 [v3d]
 [ ]  __handle_irq_event_percpu+0x1f8/0x488
 [ ]  handle_irq_event+0x88/0x128
 [ ]  handle_fasteoi_irq+0x298/0x408
 [ ]  generic_handle_domain_irq+0x50/0x78

But it is a false positive because all the queue-stats pairs have their
own lock and jobs are also one at a time.

Nevertheless we can appease lockdep by disabling local interrupts to make
it see lock usage is consistent.

Cc: Maíra Canal &lt;mcanal@igalia.com&gt;
Fixes: 6abe93b621ab ("drm/v3d: Fix race-condition between sysfs/fdinfo and interrupt handler")
Signed-off-by: Tvrtko Ursulin &lt;tvrtko.ursulin@igalia.com&gt;
Signed-off-by: Maíra Canal &lt;mcanal@igalia.com&gt;
Link: https://patchwork.freedesktop.org/patch/msgid/20240813102505.80512-2-tursulin@igalia.com
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>drm/v3d: Stop the active perfmon before being destroyed</title>
<updated>2024-10-07T12:03:57+00:00</updated>
<author>
<name>Maíra Canal</name>
<email>mcanal@igalia.com</email>
</author>
<published>2024-10-04T13:02:29+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=7d1fd3638ee3a9f9bca4785fffb638ca19120718'/>
<id>urn:sha1:7d1fd3638ee3a9f9bca4785fffb638ca19120718</id>
<content type='text'>
When running `kmscube` with one or more performance monitors enabled
via `GALLIUM_HUD`, the following kernel panic can occur:

[   55.008324] Unable to handle kernel paging request at virtual address 00000000052004a4
[   55.008368] Mem abort info:
[   55.008377]   ESR = 0x0000000096000005
[   55.008387]   EC = 0x25: DABT (current EL), IL = 32 bits
[   55.008402]   SET = 0, FnV = 0
[   55.008412]   EA = 0, S1PTW = 0
[   55.008421]   FSC = 0x05: level 1 translation fault
[   55.008434] Data abort info:
[   55.008442]   ISV = 0, ISS = 0x00000005, ISS2 = 0x00000000
[   55.008455]   CM = 0, WnR = 0, TnD = 0, TagAccess = 0
[   55.008467]   GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0
[   55.008481] user pgtable: 4k pages, 39-bit VAs, pgdp=00000001046c6000
[   55.008497] [00000000052004a4] pgd=0000000000000000, p4d=0000000000000000, pud=0000000000000000
[   55.008525] Internal error: Oops: 0000000096000005 [#1] PREEMPT SMP
[   55.008542] Modules linked in: rfcomm [...] vc4 v3d snd_soc_hdmi_codec drm_display_helper
gpu_sched drm_shmem_helper cec drm_dma_helper drm_kms_helper i2c_brcmstb
drm drm_panel_orientation_quirks snd_soc_core snd_compress snd_pcm_dmaengine snd_pcm snd_timer snd backlight
[   55.008799] CPU: 2 PID: 166 Comm: v3d_bin Tainted: G         C         6.6.47+rpt-rpi-v8 #1  Debian 1:6.6.47-1+rpt1
[   55.008824] Hardware name: Raspberry Pi 4 Model B Rev 1.5 (DT)
[   55.008838] pstate: 20000005 (nzCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[   55.008855] pc : __mutex_lock.constprop.0+0x90/0x608
[   55.008879] lr : __mutex_lock.constprop.0+0x58/0x608
[   55.008895] sp : ffffffc080673cf0
[   55.008904] x29: ffffffc080673cf0 x28: 0000000000000000 x27: ffffff8106188a28
[   55.008926] x26: ffffff8101e78040 x25: ffffff8101baa6c0 x24: ffffffd9d989f148
[   55.008947] x23: ffffffda1c2a4008 x22: 0000000000000002 x21: ffffffc080673d38
[   55.008968] x20: ffffff8101238000 x19: ffffff8104f83188 x18: 0000000000000000
[   55.008988] x17: 0000000000000000 x16: ffffffda1bd04d18 x15: 00000055bb08bc90
[   55.009715] x14: 0000000000000000 x13: 0000000000000000 x12: ffffffda1bd4cbb0
[   55.010433] x11: 00000000fa83b2da x10: 0000000000001a40 x9 : ffffffda1bd04d04
[   55.011162] x8 : ffffff8102097b80 x7 : 0000000000000000 x6 : 00000000030a5857
[   55.011880] x5 : 00ffffffffffffff x4 : 0300000005200470 x3 : 0300000005200470
[   55.012598] x2 : ffffff8101238000 x1 : 0000000000000021 x0 : 0300000005200470
[   55.013292] Call trace:
[   55.013959]  __mutex_lock.constprop.0+0x90/0x608
[   55.014646]  __mutex_lock_slowpath+0x1c/0x30
[   55.015317]  mutex_lock+0x50/0x68
[   55.015961]  v3d_perfmon_stop+0x40/0xe0 [v3d]
[   55.016627]  v3d_bin_job_run+0x10c/0x2d8 [v3d]
[   55.017282]  drm_sched_main+0x178/0x3f8 [gpu_sched]
[   55.017921]  kthread+0x11c/0x128
[   55.018554]  ret_from_fork+0x10/0x20
[   55.019168] Code: f9400260 f1001c1f 54001ea9 927df000 (b9403401)
[   55.019776] ---[ end trace 0000000000000000 ]---
[   55.020411] note: v3d_bin[166] exited with preempt_count 1

This issue arises because, upon closing the file descriptor (which happens
when we interrupt `kmscube`), the active performance monitor is not
stopped. Although all perfmons are destroyed in `v3d_perfmon_close_file()`,
the active performance monitor's pointer (`v3d-&gt;active_perfmon`) is still
retained.

If `kmscube` is run again, the driver will attempt to stop the active
performance monitor using the stale pointer in `v3d-&gt;active_perfmon`.
However, this pointer is no longer valid because the previous process has
already terminated, and all performance monitors associated with it have
been destroyed and freed.

To fix this, when the active performance monitor belongs to a given
process, explicitly stop it before destroying and freeing it.

Cc: stable@vger.kernel.org # v5.15+
Closes: https://github.com/raspberrypi/linux/issues/6389
Fixes: 26a4dc29b74a ("drm/v3d: Expose performance counters to userspace")
Signed-off-by: Maíra Canal &lt;mcanal@igalia.com&gt;
Reviewed-by: Juan A. Suarez &lt;jasuarez@igalia.com&gt;
Link: https://patchwork.freedesktop.org/patch/msgid/20241004130625.918580-2-mcanal@igalia.com
</content>
</entry>
</feed>
