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Linux kernel
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On a Sapphire Rapids system if boot without intel_iommu=on, the IDXD
driver will crash during probe in iommu_sva_bind_device().
[ 21.423729] BUG: kernel NULL pointer dereference, address: 0000000000000038
[ 21.445108] #PF: supervisor read access in kernel mode
[ 21.450912] #PF: error_code(0x0000) - not-present page
[ 21.456706] PGD 0
[ 21.459047] Oops: 0000 [#1] PREEMPT SMP NOPTI
[ 21.464004] CPU: 0 PID: 1420 Comm: kworker/0:3 Not tainted 5.19.0-0.rc3.27.eln120.x86_64 #1
[ 21.464011] Hardware name: Intel Corporation EAGLESTREAM/EAGLESTREAM, BIOS EGSDCRB1.SYS.0067.D12.2110190954 10/19/2021
[ 21.464015] Workqueue: events work_for_cpu_fn
[ 21.464030] RIP: 0010:iommu_sva_bind_device+0x1d/0xe0
[ 21.464046] Code: c3 cc 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 41 57 41 56 49 89 d6 41 55 41 54 55 53 48 83 ec 08 48 8b 87 d8 02 00 00 <48> 8b 40 38 48 8b 50 10 48 83 7a 70 00 48 89 14 24 0f 84 91 00 00
[ 21.464050] RSP: 0018:ff7245d9096b7db8 EFLAGS: 00010296
[ 21.464054] RAX: 0000000000000000 RBX: ff1eadeec8a51000 RCX: 0000000000000000
[ 21.464058] RDX: ff7245d9096b7e24 RSI: 0000000000000000 RDI: ff1eadeec8a510d0
[ 21.464060] RBP: ff1eadeec8a51000 R08: ffffffffb1a12300 R09: ff1eadffbfce25b4
[ 21.464062] R10: ffffffffffffffff R11: 0000000000000038 R12: ffffffffc09f8000
[ 21.464065] R13: ff1eadeec8a510d0 R14: ff7245d9096b7e24 R15: ff1eaddf54429000
[ 21.464067] FS: 0000000000000000(0000) GS:ff1eadee7f600000(0000) knlGS:0000000000000000
[ 21.464070] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 21.464072] CR2: 0000000000000038 CR3: 00000008c0e10006 CR4: 0000000000771ef0
[ 21.464074] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 21.464076] DR3: 0000000000000000 DR6: 00000000fffe07f0 DR7: 0000000000000400
[ 21.464078] PKRU: 55555554
[ 21.464079] Call Trace:
[ 21.464083] <TASK>
[ 21.464092] idxd_pci_probe+0x259/0x1070 [idxd]
[ 21.464121] local_pci_probe+0x3e/0x80
[ 21.464132] work_for_cpu_fn+0x13/0x20
[ 21.464136] process_one_work+0x1c4/0x380
[ 21.464143] worker_thread+0x1ab/0x380
[ 21.464147] ? _raw_spin_lock_irqsave+0x23/0x50
[ 21.464158] ? process_one_work+0x380/0x380
[ 21.464161] kthread+0xe6/0x110
[ 21.464168] ? kthread_complete_and_exit+0x20/0x20
[ 21.464172] ret_from_fork+0x1f/0x30
iommu_sva_bind_device() requires SVA has been enabled successfully on
the IDXD device before it's called. Otherwise, iommu_sva_bind_device()
will access a NULL pointer. If Intel IOMMU is disabled, SVA cannot be
enabled and thus idxd_enable_system_pasid() and iommu_sva_bind_device()
should not be called.
Fixes: 42a1b73852c4 ("dmaengine: idxd: Separate user and kernel pasid enabling")
Cc: Vinod Koul <vkoul@kernel.org>
Cc: linux-kernel@vger.kernel.org
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Link: https://lore.kernel.org/dmaengine/20220623170232.6whonfjuh3m5vcoy@cantor/
Signed-off-by: Jerry Snitselaar <jsnitsel@redhat.com>
Acked-by: Fenghua Yu <fenghua.yu@intel.com>
Link: https://lore.kernel.org/r/20220626051648.14249-1-jsnitsel@redhat.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
It seems that it is valid to have less than the requested number of
descriptors. But what is not valid and leads to subsequent errors is to
have zero descriptors. In that case, abort the probing.
Fixes: e1f7c9eee707 ("dmaengine: at_xdmac: creation of the atmel eXtended DMA Controller driver")
Signed-off-by: Michael Walle <michael@walle.cc>
Link: https://lore.kernel.org/r/20220526135111.1470926-1-michael@walle.cc
Signed-off-by: Vinod Koul <vkoul@kernel.org>
An interrupt for a channel might be pending even after struct
dma_device::device_terminate_all has been called. In that case the
recently introduced warning message "restart cyclic channel..." triggers
and the channel will be restarted. This is not desired as the channel
has just been stopped. Only restart the channel when we still have a
descriptor set for it (which will be set to NULL in
sdma_terminate_all()).
Fixes: 5b215c28b9235 ("dmaengine: imx-sdma: restart cyclic channel if needed")
Cc: stable@vger.kernel.org
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Link: https://lore.kernel.org/r/20220617115042.4004062-1-s.hauer@pengutronix.de
Signed-off-by: Vinod Koul <vkoul@kernel.org>
When the DMA is configured for more than 8 channels the bits controlling
suspend moves to another register. However when adding support for this
the new register would be completely overwritten in one case and
overwritten with values from the old register in another case.
Found by comparing the parallel implementation of more than 8 channel
support for the StarFive JH7100 SoC by Samin.
Fixes: 824351668a41 ("dmaengine: dw-axi-dmac: support DMAX_NUM_CHANNELS > 8")
Co-developed-by: Samin Guo <samin.guo@starfivetech.com>
Signed-off-by: Samin Guo <samin.guo@starfivetech.com>
Signed-off-by: Emil Renner Berthing <kernel@esmil.dk>
Link: https://lore.kernel.org/r/20220627090939.1775717-1-emil.renner.berthing@canonical.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Testing shown that when a wq mode is setup to be dedicated and then torn
down and reconfigured to shared, the wq configured end up being dedicated
anyays. The root cause is when idxd_device_wqs_clear_state() gets called
during idxd_driver removal, idxd_wq_disable_cleanup() does not get called
vs when the wq driver is removed first. The check of wq state being
"enabled" causes the cleanup to be bypassed. However, idxd_driver->remove()
releases all wq drivers. So the wqs goes to "disabled" state and will never
be "enabled". By that point, the driver has no idea if the wq was
previously configured or clean. So force call idxd_wq_disable_cleanup() on
all wqs always to make sure everything gets cleaned up.
Reported-by: Tony Zhu <tony.zhu@intel.com>
Tested-by: Tony Zhu <tony.zhu@intel.com>
Fixes: 0dcfe41e9a4c ("dmanegine: idxd: cleanup all device related bits after disabling device")
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Co-developed-by: Fenghua Yu <fenghua.yu@intel.com>
Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Link: https://lore.kernel.org/r/20220628230056.2527816-1-fenghua.yu@intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Commit dbad41e7bb5f ("dmaengine: qcom: bam_dma: check if the runtime pm enabled")
caused unbalanced pm_runtime_get/put() calls when the bam is
controlled remotely. This commit reverts it and just enables pm_runtime
in all cases, the clk_* functions already just nop when the clock is NULL.
Also clean up a bit by removing unnecessary bamclk null checks.
Suggested-by: Stephan Gerhold <stephan@gerhold.net>
Fixes: dbad41e7bb5f ("dmaengine: qcom: bam_dma: check if the runtime pm enabled")
Signed-off-by: Caleb Connolly <caleb.connolly@linaro.org>
Link: https://lore.kernel.org/r/20220629140559.118537-1-caleb.connolly@linaro.org
Signed-off-by: Vinod Koul <vkoul@kernel.org>
The revision of the imx-sdma IP that is in the i.MX8M series is the
same is that as that in the i.MX7 series but the imx7d MODULE_FIRMWARE
directive is wrapped in a condiditional which means it's not defined
when built for aarch64 SOC_IMX8M platforms and hence you get the
following errors when the driver loads on imx8m devices:
imx-sdma 302c0000.dma-controller: Direct firmware load for imx/sdma/sdma-imx7d.bin failed with error -2
imx-sdma 302c0000.dma-controller: external firmware not found, using ROM firmware
Add the SOC_IMX8M into the check so the firmware can load on i.MX8.
Fixes: 1474d48bd639 ("arm64: dts: imx8mq: Add SDMA nodes")
Fixes: 941acd566b18 ("dmaengine: imx-sdma: Only check ratio on parts that support 1:1")
Signed-off-by: Peter Robinson <pbrobinson@gmail.com>
Cc: stable@vger.kernel.org # v5.2+
Reviewed-by: Fabio Estevam <festevam@gmail.com>
Link: https://lore.kernel.org/r/20220606161034.3544803-1-pbrobinson@gmail.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
This reverts commit a8facc7b9885 ("dmaengine: add verification of
DMA_INTERRUPT capability for dmatest") as it causes regression due to
the fact that DMA_INTERRUPT in linked to dma_prep_interrupt() so
checking that is incorrect here
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Link: https://lore.kernel.org/r/20220606174906.3979283-1-vkoul@kernel.org
Signed-off-by: Vinod Koul <vkoul@kernel.org>
of_find_device_by_node() takes reference, we should use put_device()
to release it when not need anymore.
Fixes: a074ae38f859 ("dmaengine: Add driver for TI DMA crossbar on DRA7x")
Signed-off-by: Miaoqian Lin <linmq006@gmail.com>
Acked-by: Peter Ujfalusi <peter.ujfalusi@gmail.com>
Link: https://lore.kernel.org/r/20220605042723.17668-1-linmq006@gmail.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
of_parse_phandle() returns a node pointer with refcount
incremented, we should use of_node_put() on it when not needed anymore.
Add missing of_node_put() in to fix this.
Fixes: ec9bfa1e1a79 ("dmaengine: ti-dma-crossbar: dra7: Use bitops instead of idr")
Signed-off-by: Miaoqian Lin <linmq006@gmail.com>
Link: https://lore.kernel.org/r/20220605042723.17668-2-linmq006@gmail.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Pull file descriptor fix from Al Viro:
"Fix for breakage in #work.fd this window"
* tag 'pull-work.fd-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
fix the breakage in close_fd_get_file() calling conventions change
Pull mm hotfixes from Andrew Morton:
"Fixups for various recently-added and longer-term issues and a few
minor tweaks:
- fixes for material merged during this merge window
- cc:stable fixes for more longstanding issues
- minor mailmap and MAINTAINERS updates"
* tag 'mm-hotfixes-stable-2022-06-05' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm:
mm/oom_kill.c: fix vm_oom_kill_table[] ifdeffery
x86/kexec: fix memory leak of elf header buffer
mm/memremap: fix missing call to untrack_pfn() in pagemap_range()
mm: page_isolation: use compound_nr() correctly in isolate_single_pageblock()
mm: hugetlb_vmemmap: fix CONFIG_HUGETLB_PAGE_FREE_VMEMMAP_DEFAULT_ON
MAINTAINERS: add maintainer information for z3fold
mailmap: update Josh Poimboeuf's email
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