- 16 Oct, 2020 3 commits
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Chris Wilson authored
Kasan is gving a warning for passing a u32 parameter into find_first_bit (casting to a unsigned long *, with appropriate length restrictions): [ 44.678262] BUG: KASAN: stack-out-of-bounds in find_first_bit+0x2e/0x50 [ 44.678295] Read of size 8 at addr ffff888233f4fc30 by task core_hotunplug/474 [ 44.678326] [ 44.678358] CPU: 0 PID: 474 Comm: core_hotunplug Not tainted 5.9.0+ #608 [ 44.678465] Hardware name: BESSTAR (HK) LIMITED GN41/Default string, BIOS BLT-BI-MINIPC-F4G-EX3R110-GA65A-101-D 10/12/2018 [ 44.678500] Call Trace: [ 44.678534] dump_stack+0x84/0xba [ 44.678569] print_address_description.constprop.0+0x21/0x220 [ 44.678605] ? kmsg_dump_rewind_nolock+0x5f/0x5f [ 44.678638] ? _raw_spin_lock_irqsave+0x6d/0xb0 [ 44.678669] ? _raw_write_lock_irqsave+0xb0/0xb0 [ 44.678702] ? set_task_cpu+0x1e0/0x1e0 [ 44.678733] ? find_first_bit+0x2e/0x50 [ 44.678763] kasan_report.cold+0x20/0x42 [ 44.678794] ? find_first_bit+0x2e/0x50 [ 44.678825] __asan_load8+0x69/0x90 [ 44.678856] find_first_bit+0x2e/0x50 [ 44.679027] __caps_show.isra.0+0x9e/0x1f0 [i915] Since we are only using the shorter type for our own convenience, accommodate kasan and use unsigned long. Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20201013110845.16127-1-chris@chris-wilson.co.uk
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Chris Wilson authored
We may try to preempt the currently executing request, only to find that after unravelling all the dependencies that the original executing context is still the earliest in the topological sort and re-submitted back to HW (if we do detect some change in the ELSP that requires re-submission). However, due to the way we check for wrap-around during the unravelling, we mark any context that has been submitted just once (i.e. with the rq->wa_tail set, but the ring->tail earlier) as potentially wrapping and requiring a forced restore on resubmission. This was expected to be not a problem, as it was anticipated that most unwinding for preemption would result in a context switch and the few that did not would be lost in the noise. It did not take long for someone to find one particular workload where the cost of those extra context restores was measurable. However, since we know the wa_tail is of fixed size, and we know that a request must be larger than the wa_tail itself, we can safely maintain the check for request wrapping and check against a slightly future point in the ring that includes an expected wa_tail. (That is if the ring->tail is already set to rq->wa_tail, including another 8 bytes in the check does not invalidate the incremental wrap detection.) Fixes: 8ab3a381 ("drm/i915/gt: Incrementally check for rewinding") Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com> Cc: Bruce Chang <yu.bruce.chang@intel.com> Cc: Ramalingam C <ramalingam.c@intel.com> Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> Cc: <stable@vger.kernel.org> # v5.4+ Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20201002083425.4605-1-chris@chris-wilson.co.uk
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Chris Wilson authored
When running gem_exec_nop, it floods the system with many requests (with the goal of userspace submitting faster than the HW can process a single empty batch). This causes the driver to continually resubmit new requests onto the end of an active context, a flood of lite-restore preemptions. If we time this just right, Tigerlake hangs. Inserting a small delay between the processing of CS events and submitting the next context, prevents the hang. Naturally it does not occur with debugging enabled. The suspicion then is that this is related to the issues with the CS event buffer, and inserting an mmio read of the CS pointer status appears to be very successful in preventing the hang. Other registers, or uncached reads, or plain mb, do not prevent the hang, suggesting that register is key -- but that the hang can be prevented by a simple udelay, suggests it is just a timing issue like that encountered by commit 233c1ae3 ("drm/i915/gt: Wait for CSB entries on Tigerlake"). Also note that the hang is not prevented by applying CTX_DESC_FORCE_RESTORE, or by inserting a delay on the GPU between requests. Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com> Cc: Bruce Chang <yu.bruce.chang@intel.com> Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> Cc: stable@vger.kernel.org Acked-by: Mika Kuoppala <mika.kuoppala@linux.intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20201015195023.32346-1-chris@chris-wilson.co.uk
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- 15 Oct, 2020 5 commits
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Chris Wilson authored
Matthew Auld noted that on more recent systems (such as the parser for gen9) we may have objects that are larger than expected by the GEM uAPI (i.e. greater than u32). These objects would have incorrect implicit batch lengths, causing the parser to reject them for being incomplete, or worse. Based on a patch by Matthew Auld. Reported-by: Matthew Auld <matthew.auld@intel.com> Fixes: 435e8fc0 ("drm/i915: Allow parsing of unsized batches") Testcase: igt/gem_exec_params/larger-than-life-batch Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Matthew Auld <matthew.auld@intel.com> Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com> Cc: Jon Bloomfield <jon.bloomfield@intel.com> Reviewed-by: Matthew Auld <matthew.auld@intel.com> Cc: stable@vger.kernel.org Link: https://patchwork.freedesktop.org/patch/msgid/20201015115954.871-1-chris@chris-wilson.co.uk
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Chris Wilson authored
Forcing mocs:1 [used for our winsys follows-pte mode] to be cached caused display glitches. Though it is documented as deprecated (and so likely behaves as uncached) use the follow-pte bit and force it out of L3 cache. Fixes: 4d8a5cfe ("drm/i915/gt: Initialize reserved and unspecified MOCS indices") Testcase: igt/kms_frontbuffer_tracking Testcase: igt/kms_big_fb Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Ayaz A Siddiqui <ayaz.siddiqui@intel.com> Cc: Lucas De Marchi <lucas.demarchi@intel.com> Cc: Matt Roper <matthew.d.roper@intel.com> Cc: Ville Syrjälä <ville.syrjala@linux.intel.com> Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20201015122138.30161-4-chris@chris-wilson.co.uk
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Ville Syrjälä authored
Since SKL the eLLC has been sitting on the far side of the system agent, meaning the display engine can utilize it. Let's enable that. I chose WB for the caching mode, because my numbers are indicating that WT might actually be WB and WC might actually be UC. I'm not 100% sure that is indeed the case but at least my simple rendercopy based benchmark didn't see any difference in performance. Also if I configure things to do LLCeLLC+WT I still get cache dirt on my screen, suggesting that is in fact operating in WB mode anyway. This is also the reason I had to fix the MOCS target cache to really say PTE rather than LLC+eLLC. Since SKL the eLLC has been sitting on the far side of the system agent, meaning the display engine can utilize it. Let's enable that. Eero's earlier benchmarks numbers: "* Results in GfxBench and Unigine (Valley/Heaven) tests were within daily variation on the tested SKL machines * SKL GT4e (128MB eLLC) / Wayland / Weston: +15-20% SynMark TexMem512 (512MB of textures) +4-6% SynMark TerrainFly*, CSCloth, ShMapVsm -5-10% SynMark TexMem128 (128MB of textures) * SKL GT3e (64MB eLLC) / Xorg / Unity: +4-8% GpuTest Triangle fullscreen (FullHD) -5-10% GpuTest Triangle windowed (1/2 screen) * SKL GT2 (no eLLC) / Xorg / Unity: * Some of the higher FPS SynMark pixel and vertex shader tests are few percent higher, more than daily variance => Do you see any reason why this machine would be impacted although it doesn't eLLC?" Caveats: - Still haven't tested with a prime setup - Still not entirely sure this a good idea, but I've been using it on my cfl anyway :) v2: Split the MOCS PTE change out Cc: Eero Tamminen <eero.t.tamminen@intel.com> Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk> Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Link: https://patchwork.freedesktop.org/patch/msgid/20201007120329.17076-3-ville.syrjala@linux.intel.com Link: https://patchwork.freedesktop.org/patch/msgid/20201015122138.30161-3-chris@chris-wilson.co.uk
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Ville Syrjälä authored
Fix up the MOCS PTE setting to really get the LLC cacheability from the PTE rather than hardocoding it to LLC or LLC+eLLC. Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk> Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Link: https://patchwork.freedesktop.org/patch/msgid/20201007120329.17076-2-ville.syrjala@linux.intel.com Link: https://patchwork.freedesktop.org/patch/msgid/20201015122138.30161-2-chris@chris-wilson.co.uk
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Ville Syrjälä authored
Currently we leave the cache_level of the initial fb obj set to NONE. This means on eLLC machines the first pin_to_display() will try to switch it to WT which requires a vma unbind+bind. If that happens during the fbdev initialization rcu does not seem operational which causes the unbind to get stuck. To most appearances this looks like a dead machine on boot. Avoid the unbind by already marking the object cache_level as WT when creating it. We still do an excplicit ggtt pin which will rewrite the PTEs anyway, so they will match whatever cache level we set. Cc: <stable@vger.kernel.org> # v5.7+ Suggested-by: Chris Wilson <chris@chris-wilson.co.uk> Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/2381Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk> Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Link: https://patchwork.freedesktop.org/patch/msgid/20201007120329.17076-1-ville.syrjala@linux.intel.com Link: https://patchwork.freedesktop.org/patch/msgid/20201015122138.30161-1-chris@chris-wilson.co.uk
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- 13 Oct, 2020 1 commit
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Ayaz A Siddiqui authored
In order to avoid functional breakage of mis-programmed applications that have grown to depend on unused MOCS entries, we are programming those entries to be equal to fully cached ("L3 + LLC") entry. These reserved and unspecified entries should not be used as they may be changed to less performant variants with better coherency in the future if more entries are needed. v2: As suggested by Lucas De Marchi to utilise __init_mocs_table for programming default value, setting I915_MOCS_PTE index of tgl_mocs_table with desired value. Cc: Chris Wilson <chris@chris-wilson.co.uk> Cc: Lucas De Marchi <lucas.demarchi@intel.com> Cc: Tomasz Lis <tomasz.lis@intel.com> Cc: Matt Roper <matthew.d.roper@intel.com> Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> Cc: Francisco Jerez <currojerez@riseup.net> Cc: Mathew Alwin <alwin.mathew@intel.com> Cc: Mcguire Russell W <russell.w.mcguire@intel.com> Cc: Spruit Neil R <neil.r.spruit@intel.com> Cc: Zhou Cheng <cheng.zhou@intel.com> Cc: Benemelis Mike G <mike.g.benemelis@intel.com> Signed-off-by: Ayaz A Siddiqui <ayaz.siddiqui@intel.com> Reviewed-by: Lucas De Marchi <lucas.demarchi@intel.com> Acked-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Link: https://patchwork.freedesktop.org/patch/msgid/20200729102539.134731-2-ayaz.siddiqui@intel.com Cc: stable@vger.kernel.org
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- 07 Oct, 2020 1 commit
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Chris Wilson authored
Since we track the idle_pulse for flushing the barriers and avoid re-emitting the pulse upon idling if no futher action is required, this also impacts the heartbeat. Before emitting a fresh heartbeat, we look at the engine idle status and assume that if the pulse was the last request emitted along the heartbeat, the engine is idling and a heartbeat pulse not required. This assumption fails, but we can reuse the idle pulse as the heartbeat if we are yet to emit one, and so track the status of that pulse for our engine health check. This impacts tgl/rcs0 as we rely on the heartbeat for our healthcheck for the normal preemption detection mechanism is disabled by default. Testcase: igt/gem_exec_schedule/preempt-hang/rcs0 #tgl Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20201006094653.7558-1-chris@chris-wilson.co.uk
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- 06 Oct, 2020 4 commits
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Tvrtko Ursulin authored
As the previous patch fixed the places where we walk the whole scatterlist for DMA addresses, this patch fixes the random lookup functionality. To achieve this we have to add a second lookup iterator and add a i915_gem_object_get_sg_dma helper, to be used analoguous to existing i915_gem_object_get_sg_dma. Therefore two lookup caches are maintained per object and they are flushed at the same point for simplicity. (Strictly speaking the DMA cache should be flushed from i915_gem_gtt_finish_pages, but today this conincides with unsetting of the pages in general.) Partial VMA view is then fixed to use the new DMA lookup and properly query sg length. v2: * Checkpatch. Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> Cc: Chris Wilson <chris@chris-wilson.co.uk> Cc: Matthew Auld <matthew.auld@intel.com> Cc: Lu Baolu <baolu.lu@linux.intel.com> Cc: Tom Murphy <murphyt7@tcd.ie> Cc: Logan Gunthorpe <logang@deltatee.com> Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk> Link: https://patchwork.freedesktop.org/patch/msgid/20201006092508.1064287-2-tvrtko.ursulin@linux.intel.com
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Tvrtko Ursulin authored
When walking DMA mapped scatterlists sg_dma_len has to be used since it can be different (coalesced) from the backing store entry. This also means we have to end the walk when encountering a zero length DMA entry and cannot rely on the normal sg list end marker. Both issues were there in theory for some time but were hidden by the fact Intel IOMMU driver was never coalescing entries. As there are ongoing efforts to change this we need to start handling it. v2: * Use unsigned int for local storing sg_dma_len. (Logan) Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com> References: 85d1225e ("drm/i915: Introduce & use new lightweight SGL iterators") References: b31144c0 ("drm/i915: Micro-optimise gen6_ppgtt_insert_entries()") Reported-by: Tom Murphy <murphyt7@tcd.ie> Suggested-by: Tom Murphy <murphyt7@tcd.ie> # __sgt_iter Suggested-by: Logan Gunthorpe <logang@deltatee.com> # __sgt_iter Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> Cc: Chris Wilson <chris@chris-wilson.co.uk> Cc: Matthew Auld <matthew.auld@intel.com> Cc: Lu Baolu <baolu.lu@linux.intel.com> Reviewed-by: Logan Gunthorpe <logang@deltatee.com> Link: https://patchwork.freedesktop.org/patch/msgid/20201006092508.1064287-1-tvrtko.ursulin@linux.intel.com
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Chris Wilson authored
Currently we do a final scrub of the HW state upon release. However, when rebinding the device, this is too late as the device may either have been partially rebound or the device is no longer accessible. If the device has been removed before release, the reset goes astray leaving the device in an inconsistent state, unlikely to work without a full PCI reset. Furthermore, if the device is partially rebound before the HW scrubbing, there may be leftover HW state that should have been scrubbed. Either way, we need to push the scrubbing earlier before the removal, so into unregister. The danger is that on older machines, resetting the GPU also impact the display engine and so the reset should be after modesetting is disabled (and before reuse we need to recover modesetting). Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/2508 Testcase: igt/core_hotunplug Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20200929112639.24223-1-chris@chris-wilson.co.uk
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Chris Wilson authored
Though less likely in practice, igt uses MI_NOOP frequently to pad out its batch buffers. The lookup and valiation of so many MI_NOOP command descriptions is noticeable, though the side-effect of poisoning the last-validated-command cache is more likely to impact upon real CS. Testcase: igt/gen9_exec_parse/bb-large Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20201001102632.18789-1-chris@chris-wilson.co.uk
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- 30 Sep, 2020 3 commits
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Chris Wilson authored
If we manage to hit the intel_gt_set_wedged_on_fini() while active, i.e. module unload during a stress test, we may cancel the requests but not clean up. This leads to a very slow module unload as we wait for something or other to trigger the retirement flushing, or timeout and unload with a bunch of warnings. Instead if we explicitly cancel then cleanup on an active unload, it should be instant and quiet. Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Reviewed-by: Matthew Auld <matthew.auld@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20200930163253.2789-3-chris@chris-wilson.co.uk
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Chris Wilson authored
Flush all the pending requests from the mock engine when they are cancelled. Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Reviewed-by: Matthew Auld <matthew.auld@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20200930163253.2789-2-chris@chris-wilson.co.uk
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Chris Wilson authored
After marking the requests on an engine as cancelled upon wedging, send any signals for their completions. Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Reviewed-by: Matthew Auld <matthew.auld@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20200930163253.2789-1-chris@chris-wilson.co.uk
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- 29 Sep, 2020 4 commits
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Chris Wilson authored
Be consistent and use unsigned long throughout the chunk copies to avoid the inherent clumsiness of mixing integer types of different widths and signs. Failing to take acount of a wider unsigned type when using min_t can lead to treating it as a negative, only for it flip back to a large unsigned value after passing a boundary check. Fixes: ed13033f ("drm/i915/cmdparser: Only cache the dst vmap") Testcase: igt/gen9_exec_parse/bb-large Reported-by: "Candelaria, Jared" <jared.candelaria@intel.com> Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com> Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> Cc: "Candelaria, Jared" <jared.candelaria@intel.com> Cc: "Bloomfield, Jon" <jon.bloomfield@intel.com> Cc: <stable@vger.kernel.org> # v4.9+ Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20200928215942.31917-1-chris@chris-wilson.co.uk
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Chris Wilson authored
Verify that if a context is active at the time it is closed, that it is either persistent and preemptible (with hangcheck running) or it shall be removed from execution. Fixes: 9a40bddd ("drm/i915/gt: Expose heartbeat interval via sysfs") Testcase: igt/gem_ctx_persistence/heartbeat-close Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> Cc: <stable@vger.kernel.org> # v5.7+ Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Acked-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20200928221510.26044-3-chris@chris-wilson.co.uk
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Chris Wilson authored
Currently, we check we can send a pulse prior to disabling the heartbeat to verify that we can change the heartbeat, but since we may re-evaluate execution upon changing the heartbeat interval we need another pulse afterwards to refresh execution. v2: Tvrtko asked if we could reduce the double pulse to a single, which opened up a discussion of how we should handle the pulse-error after attempting to change the property, and the desire to serialise adjustment of the property with its validating pulse, and unwind upon failure. Fixes: 9a40bddd ("drm/i915/gt: Expose heartbeat interval via sysfs") Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Cc: <stable@vger.kernel.org> # v5.7+ Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Acked-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20200928221510.26044-2-chris@chris-wilson.co.uk
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Chris Wilson authored
We only allow persistent requests to remain on the GPU past the closure of their containing context (and process) so long as they are continuously checked for hangs or allow other requests to preempt them, as we need to ensure forward progress of the system. If we allow persistent contexts to remain on the system after the the hangcheck mechanism is disabled, the system may grind to a halt. On disabling the mechanism, we sent a pulse along the engine to remove all executing contexts from the engine which would check for hung contexts -- but we did not prevent those contexts from being resubmitted if they survived the final hangcheck. Fixes: 9a40bddd ("drm/i915/gt: Expose heartbeat interval via sysfs") Testcase: igt/gem_ctx_persistence/heartbeat-stop Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> Cc: <stable@vger.kernel.org> # v5.7+ Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Acked-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20200928221510.26044-1-chris@chris-wilson.co.uk
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- 26 Sep, 2020 2 commits
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Chris Wilson authored
We have to be very careful while walking the timeline->requests list under the RCU guard, as the requests (and so rq->link) use SLAB_TYPESAFE_BY_RCU and so the requests may be reallocated within an rcu grace period. As the requests are reallocated, they are removed from one list and placed on another, and if we are iterating over that request at that moment, the list iteration jumps from one list to the next and promptly gets confused. Verify we hold the request reference to ensure that the request is not added to a new list behind our backs. <4> [582.745252] general protection fault, probably for non-canonical address 0xcccccccccccccd5c: 0000 [#1] PREEMPT SMP PTI <4> [582.745297] CPU: 0 PID: 1475 Comm: gem_ctx_persist Not tainted 5.9.0-rc1-CI-CI_DRM_8908+ #1 <4> [582.745304] Hardware name: Intel Corporation NUC7CJYH/NUC7JYB, BIOS JYGLKCPX.86A.0027.2018.0125.1347 01/25/2018 <4> [582.745317] RIP: 0010:__lock_acquire+0x2c3/0x1f40 <4> [582.745323] Code: 00 65 8b 05 c7 8a ef 7e 85 c0 0f 85 b4 07 00 00 44 8b 9d c4 08 00 00 45 85 db 0f 84 0f 01 00 00 ba 05 00 00 00 e9 c8 06 00 00 <48> 81 3f c0 89 c7 82 b8 00 00 00 00 41 0f 45 c0 83 fe 01 41 89 c3 <4> [582.745334] RSP: 0018:ffffc9000461bc40 EFLAGS: 00010002 <4> [582.745340] RAX: 0000000000000000 RBX: 0000000000000001 RCX: 0000000000000000 <4> [582.745345] RDX: 0000000000000000 RSI: 0000000000000000 RDI: cccccccccccccd5c <4> [582.745350] RBP: ffff8881ec4a2880 R08: 0000000000000001 R09: 0000000000000001 <4> [582.745356] R10: 0000000000000001 R11: 0000000000000001 R12: 0000000000000000 <4> [582.745361] R13: 0000000000000000 R14: 0000000000000000 R15: cccccccccccccd5c <4> [582.745367] FS: 00007fb44da78e40(0000) GS:ffff888278000000(0000) knlGS:0000000000000000 <4> [582.745373] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 <4> [582.745378] CR2: 00007fb44daad040 CR3: 0000000268428000 CR4: 0000000000350ef0 <4> [582.745383] Call Trace: <4> [582.745390] ? __lock_acquire+0x913/0x1f40 <4> [582.745397] lock_acquire+0xb5/0x3c0 <4> [582.745526] ? kill_engines+0x19a/0x4b0 [i915] <4> [582.745533] ? find_held_lock+0x2d/0x90 <4> [582.745541] _raw_spin_lock_irq+0x30/0x40 <4> [582.745635] ? kill_engines+0x19a/0x4b0 [i915] <4> [582.745727] kill_engines+0x19a/0x4b0 [i915] <4> [582.745820] context_close+0x195/0x410 [i915] <4> [582.745912] i915_gem_context_close+0x5b/0x160 [i915] <4> [582.745994] i915_driver_postclose+0x14/0x40 [i915] <4> [582.746003] drm_file_free.part.13+0x240/0x290 <4> [582.746009] drm_release_noglobal+0x16/0x50 <4> [582.746016] __fput+0xa5/0x250 <4> [582.746021] task_work_run+0x6e/0xb0 <4> [582.746028] exit_to_user_mode_prepare+0x178/0x180 <4> [582.746034] syscall_exit_to_user_mode+0x36/0x220 <4> [582.746040] entry_SYSCALL_64_after_hwframe+0x44/0xa9 <4> [582.746045] RIP: 0033:0x7fb44d1dc421 <4> [582.746050] Code: f7 d8 64 89 02 48 c7 c0 ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 8b 05 ea cf 20 00 85 c0 75 16 b8 03 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 3f f3 c3 0f 1f 44 00 00 53 89 fb 48 83 ec 10 <4> [582.746062] RSP: 002b:00007ffed2e83818 EFLAGS: 00000246 ORIG_RAX: 0000000000000003 <4> [582.746069] RAX: 0000000000000000 RBX: 0000556410bfe840 RCX: 00007fb44d1dc421 <4> [582.746075] RDX: 000000000000000a RSI: 00000000c0406469 RDI: 0000000000000008 <4> [582.746080] RBP: 0000000000000008 R08: 00007fb44d1c51cc R09: 00007fb44d1c5240 <4> [582.746086] R10: 0000000000000001 R11: 0000000000000246 R12: 00000000fffffffb <4> [582.746091] R13: 0000000000000006 R14: 0000000000000000 R15: 000000000000000a <4> [582.746099] Modules linked in: vgem mei_hdcp snd_hda_codec_hdmi snd_hda_codec_realtek snd_hda_codec_generic ledtrig_audio btusb btrtl btbcm btintel x86_pkg_temp_thermal coretemp crct10dif_pclmul crc32_pclmul bluetooth ghash_clmulni_intel ecdh_generic ecc i915 r8169 realtek mei_me mei snd_hda_intel i2c_hid snd_intel_dspcfg snd_hda_codec snd_hwdep snd_hda_core snd_pcm pinctrl_geminilake pinctrl_intel prime_numbers [last unloaded: test_drm_mm] Fixes: 736e785f ("drm/i915/gem: Reduce context termination list iteration guard to RCU") Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20200925101107.27869-2-chris@chris-wilson.co.uk
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Chris Wilson authored
The reordering and rebasing of commit 2e4c6c1a ("drm/i915: Remove i915_request.lock requirement for execution callbacks") caused it to revert an earlier correction. Let us restore commit 99f0a640d464 ("drm/i915: Remove requirement for holding i915_request.lock for breadcrumbs") Fixes: 2e4c6c1a ("drm/i915: Remove i915_request.lock requirement for execution callbacks") Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Cc: Rodrigo Vivi <rodrigo.vivi@intel.com> Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20200925101107.27869-1-chris@chris-wilson.co.uk
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- 24 Sep, 2020 1 commit
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Chris Wilson authored
Since the debugfs may peek into the GEM contexts as the corresponding client/fd is being closed, we may try and follow a dangling pointer. However, the context closure itself is serialised with the ctx->mutex, so if we hold that mutex as we inspect the state coupled in the context, we know the pointers within the context are stable and will remain valid as we inspect their tables. Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: CQ Tang <cq.tang@intel.com> Cc: Daniel Vetter <daniel.vetter@intel.com> Cc: stable@vger.kernel.org Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20200723172119.17649-3-chris@chris-wilson.co.uk
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- 23 Sep, 2020 1 commit
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Jani Nikula authored
The GuC communication enabled/disabled messages are too noisy in info level. Convert them from info to debug level, and switch to device based logging while at it. Reported-by: Karol Herbst <kherbst@redhat.com> Cc: Karol Herbst <kherbst@redhat.com> Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Signed-off-by: Jani Nikula <jani.nikula@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20200917165056.29766-1-jani.nikula@intel.com
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- 22 Sep, 2020 1 commit
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Matthew Auld authored
If we are really unlucky and encounter an error during i915_vm_alloc_pt_stash, we end up passing an empty pt/pd stash all the way down into the low-level ppgtt alloc code, leading to explosions, since it expects at least the required number of pt/pd for the va range. [ 211.981418] BUG: kernel NULL pointer dereference, address: 0000000000000000 [ 211.981421] #PF: supervisor read access in kernel mode [ 211.981422] #PF: error_code(0x0000) - not-present page [ 211.981424] PGD 80000008439cb067 P4D 80000008439cb067 PUD 84a37f067 PMD 0 [ 211.981427] Oops: 0000 [#1] SMP PTI [ 211.981428] CPU: 1 PID: 1301 Comm: i915_selftest Tainted: G U I 5.9.0-rc5+ #3 [ 211.981430] Hardware name: /NUC6i7KYB, BIOS KYSKLi70.86A.0050.2017.0831.1924 08/31/2017 [ 211.981521] RIP: 0010:__gen8_ppgtt_alloc+0x1ed/0x3c0 [i915] [ 211.981523] Code: c1 48 c7 c7 5d 5d fe c0 65 ff 0d ee 1d 03 3f e8 d9 91 1f e2 8b 55 c4 31 c0 48 8b 75 b8 85 d2 0f 95 c0 48 8b 1c c6 48 89 45 98 <48> 8b 03 48 8b 90 58 02 00 00 48 85 d2 0f 84 07 ea 15 00 48 81 fa [ 211.981526] RSP: 0018:ffffba2cc0eb3970 EFLAGS: 00010202 [ 211.981527] RAX: 0000000000000001 RBX: 0000000000000000 RCX: 0000000000000004 [ 211.981529] RDX: 0000000000000002 RSI: ffff9be998bdb8c0 RDI: ffff9be99c844300 [ 211.981530] RBP: ffffba2cc0eb39d8 R08: 0000000000000640 R09: ffff9be97cdfd000 [ 211.981531] R10: ffff9be97cdfd614 R11: 0000000000000000 R12: 0000000000000000 [ 211.981532] R13: ffff9be98607ba20 R14: ffff9be995a0b400 R15: ffffba2cc0eb39e8 [ 211.981534] FS: 00007f0f10b31000(0000) GS:ffff9be99fc40000(0000) knlGS:0000000000000000 [ 211.981536] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 211.981538] CR2: 0000000000000000 CR3: 000000084d74e006 CR4: 00000000003706e0 [ 211.981539] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 211.981541] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 211.981542] Call Trace: [ 211.981609] gen8_ppgtt_alloc+0x79/0x90 [i915] [ 211.981678] ppgtt_bind_vma+0x36/0x80 [i915] [ 211.981756] __vma_bind+0x39/0x40 [i915] [ 211.981818] fence_work+0x21/0x98 [i915] [ 211.981879] fence_notify+0x8d/0x128 [i915] [ 211.981939] __i915_sw_fence_complete+0x62/0x240 [i915] [ 211.982018] i915_vma_pin_ww+0x1ee/0x9c0 [i915] Fixes: cd0452aa ("drm/i915: Preallocate stashes for vma page-directories") Signed-off-by: Matthew Auld <matthew.auld@intel.com> Cc: Chris Wilson <chris@chris-wilson.co.uk> Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk> Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Link: https://patchwork.freedesktop.org/patch/msgid/20200921160844.73186-1-matthew.auld@intel.com
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- 21 Sep, 2020 1 commit
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Maarten Lankhorst authored
In case backoff fails with an error, we return an undefined rq, assign err to rq correctly. Fixes: 8a929c9e ("drm/i915: Use ww pinning for intel_context_create_request()") Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20200918111208.1392128-1-maarten.lankhorst@linux.intel.comReviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
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- 18 Sep, 2020 4 commits
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Chris Wilson authored
As the last user was eliminated in commit e21fecdcde40 ("drm/i915/gt: Distinguish the virtual breadcrumbs from the irq breadcrumbs"), we can remove the function. One less implementation detail creeping beyond its scope. Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20200826132811.17577-16-chris@chris-wilson.co.uk
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Chris Wilson authored
Shrink the hold time for the error capture mutex to just around the acquire/release of the PTE used for reading back the object via the Global GTT. For platforms that do not need the GGTT read back, we can skip the mutex entirely and allow concurrent error capture. Where we do use the GGTT, by restricting the hold time around the slow readback and compression, we are more resilient against softlockups (khungtaskd) as the heartbeat may well also trigger an error while the first is on going, and this allows the heartbeat reset to skip past the capture and not be stalled. Testcase: igt/gem_exec_capture/many-* Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com> Reviewed-by: Matthew Auld <matthew.auld@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20200916090059.3189-3-chris@chris-wilson.co.uk
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Chris Wilson authored
As the error capture will compress user buffers as directed to by the user, it can take an arbitrary amount of time and space. Break up the compression loops with a call to cond_resched(), that will allow other processes to schedule (avoiding the soft lockups) and also serve as a warning should we try to make this loop atomic in the future. Testcase: igt/gem_exec_capture/many-* Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com> Cc: stable@vger.kernel.org Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20200916090059.3189-2-chris@chris-wilson.co.uk
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Chris Wilson authored
When debugging the engine state, include the user properties that may, or may not, have been adjusted by the user/test. For example, vecs0 ... Properties: heartbeat_interval_ms: 2500 [default 2500] max_busywait_duration_ns: 8000 [default 8000] preempt_timeout_ms: 640 [default 640] stop_timeout_ms: 100 [default 100] timeslice_duration_ms: 1 [default 1] Suggested-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com> Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20200916090059.3189-1-chris@chris-wilson.co.uk
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- 17 Sep, 2020 1 commit
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Dan Carpenter authored
This code should use "vma[1]" instead of "vma". The "vma" variable is a valid pointer. Fixes: 6b050304 ("drm/i915: Convert i915_gem_object/client_blt.c to use ww locking as well, v2.") Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com> Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20200911075243.GG12635@kadam
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- 15 Sep, 2020 8 commits
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Chris Wilson authored
If we find the GPU didn't update the CSB within 50us, we currently fail and eventually reset the GPU. Lets report the value from the mmio space as a last resort, it may just stave off an unnecessary GPU reset. References: HSDES#22011327657 Suggested-by: Mika Kuoppala <mika.kuoppala@linux.intel.com> Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com> Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20200915134923.30088-4-chris@chris-wilson.co.uk
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Chris Wilson authored
Since we expect to inline the csb_parse() routines, the w/a for the stale CSB data on Tigerlake will be pulled into process_csb(), and so we might as well simply reuse the logic for all, and so will hopefully avoid any strange behaviour on Icelake that was not covered by our previous w/a. References: d8f50531 ("drm/i915/icl: Forcibly evict stale csb entries") Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com> Cc: Bruce Chang <yu.bruce.chang@intel.com> Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20200915134923.30088-3-chris@chris-wilson.co.uk
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Chris Wilson authored
On Tigerlake, we are seeing a repeat of commit d8f50531 ("drm/i915/icl: Forcibly evict stale csb entries") where, presumably, due to a missing Global Observation Point synchronisation, the write pointer of the CSB ringbuffer is updated _prior_ to the contents of the ringbuffer. That is we see the GPU report more context-switch entries for us to parse, but those entries have not been written, leading us to process stale events, and eventually report a hung GPU. However, this effect appears to be much more severe than we previously saw on Icelake (though it might be best if we try the same approach there as well and measure), and Bruce suggested the good idea of resetting the CSB entry after use so that we can detect when it has been updated by the GPU. By instrumenting how long that may be, we can set a reliable upper bound for how long we should wait for: 513 late, avg of 61 retries (590 ns), max of 1061 retries (10099 ns) Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/2045 References: d8f50531 ("drm/i915/icl: Forcibly evict stale csb entries") References: HSDES#22011327657, HSDES#1508287568 Suggested-by: Bruce Chang <yu.bruce.chang@intel.com> Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Bruce Chang <yu.bruce.chang@intel.com> Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com> Cc: stable@vger.kernel.org # v5.4 Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20200915134923.30088-2-chris@chris-wilson.co.uk
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Chris Wilson authored
A CSB entry is 64b, and it is simpler for us to treat it as an array of 64b entries than as an array of pairs of 32b entries. Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com> Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20200915134923.30088-1-chris@chris-wilson.co.uk
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Chris Wilson authored
If the ips module calls into the driver during an unbind/bind cycle, we may see the driver while it has unregistered itself from ips and try and dereference a NULL ips_mchdev pointer. <1> [211.928844] BUG: kernel NULL pointer dereference, address: 0000000000000014 <1> [211.928861] #PF: supervisor read access in kernel mode <1> [211.928871] #PF: error_code(0x0000) - not-present page <6> [211.928881] PGD 0 P4D 0 <4> [211.928890] Oops: 0000 [#1] PREEMPT SMP PTI <4> [211.928900] CPU: 3 PID: 327 Comm: ips-monitor Not tainted 5.9.0-rc5-CI-CI_DRM_9008+ #1 <4> [211.928914] Hardware name: Hewlett-Packard HP EliteBook 8440p/172A, BIOS 68CCU Ver. F.24 09/13/2013 <4> [211.929056] RIP: 0010:mchdev_get+0x5a/0x180 [i915] <4> [211.929067] Code: c0 5a 74 0d 80 3d f1 53 29 00 00 0f 84 ab 00 00 00 48 8b 1d c8 a8 29 00 e8 d3 18 89 e1 85 c0 74 09 80 3d d1 53 29 00 00 74 65 <8b> 4b 14 48 8d 7b 14 85 c9 0f 84 09 01 00 00 8d 51 01 89 c8 f0 0f <4> [211.929095] RSP: 0018:ffffc900002efe60 EFLAGS: 00010202 <4> [211.929105] RAX: 0000000000000001 RBX: 0000000000000000 RCX: ffff8881297acf40 <4> [211.929118] RDX: 0000000000000000 RSI: ffffffff8264e2c0 RDI: ffff8881297ad820 <4> [211.929130] RBP: ffffc900002efe68 R08: ffff8881297ad820 R09: 00000000fffffffe <4> [211.929143] R10: ffff8881297acf40 R11: 00000000fff74c96 R12: ffff8881294dfa18 <4> [211.929155] R13: 0000000000000067 R14: ffff888126eff640 R15: ffff888126efe840 <4> [211.929168] FS: 0000000000000000(0000) GS:ffff888133d80000(0000) knlGS:0000000000000000 <4> [211.929182] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 <4> [211.929194] CR2: 0000000000000014 CR3: 0000000002610000 CR4: 00000000000006e0 <4> [211.929206] Call Trace: <4> [211.929294] i915_read_mch_val+0x15/0x380 [i915] <4> [211.929309] ? ips_monitor+0x3fb/0x630 [intel_ips] <4> [211.929321] ips_monitor+0x53c/0x630 [intel_ips] <4> [211.929334] ? ips_gpu_lower+0x30/0x30 [intel_ips] <4> [211.929348] kthread+0x14d/0x170 <4> [211.929358] ? kthread_park+0x80/0x80 <4> [211.929369] ret_from_fork+0x22/0x30 <4> [211.929382] Modules linked in: vgem snd_hda_codec_hdmi snd_hda_codec_generic ledtrig_audio i915 coretemp crct10dif_pclmul crc32_pclmul ghash_clmulni_intel snd_hda_intel snd_intel_dspcfg snd_hda_codec snd_hwdep snd_hda_core e1000e snd_pcm mei_me mei intel_ips lpc_ich ptp prime_numbers pps_core <4> [211.929437] CR2: 0000000000000014 Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20200915105113.26564-1-chris@chris-wilson.co.uk
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Chris Wilson authored
If we create a new node, it is possible for the slab allocator to return us a recently freed node. If that node was just retired, it will retain the current jiffy as its node->age. There is then a miniscule window, where as that node is retired, it will appear on the free list with an incorrect age and be eligible for reuse by one thread, and then by a second thread as the correct node->age is written. Fixes: 06b73c2d ("drm/i915/gt: Delay taking the spinlock for grabbing from the buffer pool") Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Reviewed-by: Matthew Auld <matthew.auld@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20200915091417.4086-3-chris@chris-wilson.co.uk
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Chris Wilson authored
Let's not try and use PAT attributes for I915_MAP_WC if the CPU doesn't support PAT. Fixes: 6056e500 ("drm/i915/gem: Support discontiguous lmem object maps") Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Reviewed-by: Matthew Auld <matthew.auld@intel.com> Cc: <stable@vger.kernel.org> # v5.6+ Link: https://patchwork.freedesktop.org/patch/msgid/20200915091417.4086-2-chris@chris-wilson.co.uk
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Chris Wilson authored
On 32b, highmem using a finite set of indirect PTE (i.e. vmap) to provide virtual mappings of the high pages. As these are finite, map_new_virtual() must wait for some other kmap() to finish when it runs out. If we map a large number of objects, there is no method for it to tell us to release the mappings, and we deadlock. However, if we make an explicit vmap of the page, that uses a larger vmalloc arena, and also has the ability to tell us to release unwanted mappings. Most importantly, it will fail and propagate an error instead of waiting forever. Fixes: fb8621d3 ("drm/i915: Avoid allocating a vmap arena for a single page") #x86-32 References: e87666b5 ("drm/i915/shrinker: Hook up vmap allocation failure notifier") Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Reviewed-by: Matthew Auld <matthew.auld@intel.com> Cc: <stable@vger.kernel.org> # v4.7+ Link: https://patchwork.freedesktop.org/patch/msgid/20200915091417.4086-1-chris@chris-wilson.co.uk
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