linux-stable.git/drivers, branch v6.6.71 Linux kernel stable tree x86/hyperv: Fix hv tsc page based sched_clock for hibernation 2025-01-10T13:31:36+00:00 Naman Jain namjain@linux.microsoft.com 2024-09-17T05:39:17+00:00 a6923798e471570ac1b24086be0a9679f51c3171 commit bcc80dec91ee745b3d66f3e48f0ec2efdea97149 upstream. read_hv_sched_clock_tsc() assumes that the Hyper-V clock counter is bigger than the variable hv_sched_clock_offset, which is cached during early boot, but depending on the timing this assumption may be false when a hibernated VM starts again (the clock counter starts from 0 again) and is resuming back (Note: hv_init_tsc_clocksource() is not called during hibernation/resume); consequently, read_hv_sched_clock_tsc() may return a negative integer (which is interpreted as a huge positive integer since the return type is u64) and new kernel messages are prefixed with huge timestamps before read_hv_sched_clock_tsc() grows big enough (which typically takes several seconds). Fix the issue by saving the Hyper-V clock counter just before the suspend, and using it to correct the hv_sched_clock_offset in resume. This makes hv tsc page based sched_clock continuous and ensures that post resume, it starts from where it left off during suspend. Override x86_platform.save_sched_clock_state and x86_platform.restore_sched_clock_state routines to correct this as soon as possible. Note: if Invariant TSC is available, the issue doesn't happen because 1) we don't register read_hv_sched_clock_tsc() for sched clock: See commit e5313f1c5404 ("clocksource/drivers/hyper-v: Rework clocksource and sched clock setup"); 2) the common x86 code adjusts TSC similarly: see __restore_processor_state() -> tsc_verify_tsc_adjust(true) and x86_platform.restore_sched_clock_state(). Cc: stable@vger.kernel.org Fixes: 1349401ff1aa ("clocksource/drivers/hyper-v: Suspend/resume Hyper-V clocksource for hibernation") Co-developed-by: Dexuan Cui <decui@microsoft.com> Signed-off-by: Dexuan Cui <decui@microsoft.com> Signed-off-by: Naman Jain <namjain@linux.microsoft.com> Reviewed-by: Michael Kelley <mhklinux@outlook.com> Link: https://lore.kernel.org/r/20240917053917.76787-1-namjain@linux.microsoft.com Signed-off-by: Wei Liu <wei.liu@kernel.org> Message-ID: <20240917053917.76787-1-namjain@linux.microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit bcc80dec91ee745b3d66f3e48f0ec2efdea97149 upstream.

read_hv_sched_clock_tsc() assumes that the Hyper-V clock counter is
bigger than the variable hv_sched_clock_offset, which is cached during
early boot, but depending on the timing this assumption may be false
when a hibernated VM starts again (the clock counter starts from 0
again) and is resuming back (Note: hv_init_tsc_clocksource() is not
called during hibernation/resume); consequently,
read_hv_sched_clock_tsc() may return a negative integer (which is
interpreted as a huge positive integer since the return type is u64)
and new kernel messages are prefixed with huge timestamps before
read_hv_sched_clock_tsc() grows big enough (which typically takes
several seconds).

Fix the issue by saving the Hyper-V clock counter just before the
suspend, and using it to correct the hv_sched_clock_offset in
resume. This makes hv tsc page based sched_clock continuous and ensures
that post resume, it starts from where it left off during suspend.
Override x86_platform.save_sched_clock_state and
x86_platform.restore_sched_clock_state routines to correct this as soon
as possible.

Note: if Invariant TSC is available, the issue doesn't happen because
1) we don't register read_hv_sched_clock_tsc() for sched clock:
See commit e5313f1c5404 ("clocksource/drivers/hyper-v: Rework
clocksource and sched clock setup");
2) the common x86 code adjusts TSC similarly: see
__restore_processor_state() ->  tsc_verify_tsc_adjust(true) and
x86_platform.restore_sched_clock_state().

Cc: stable@vger.kernel.org
Fixes: 1349401ff1aa ("clocksource/drivers/hyper-v: Suspend/resume Hyper-V clocksource for hibernation")
Co-developed-by: Dexuan Cui <decui@microsoft.com>
Signed-off-by: Dexuan Cui <decui@microsoft.com>
Signed-off-by: Naman Jain <namjain@linux.microsoft.com>
Reviewed-by: Michael Kelley <mhklinux@outlook.com>
Link: https://lore.kernel.org/r/20240917053917.76787-1-namjain@linux.microsoft.com
Signed-off-by: Wei Liu <wei.liu@kernel.org>
Message-ID: <20240917053917.76787-1-namjain@linux.microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Revert "x86/hyperv: Fix hv tsc page based sched_clock for hibernation" 2025-01-10T13:31:36+00:00 Greg Kroah-Hartman gregkh@linuxfoundation.org 2025-01-10T12:06:34+00:00 c8bc44c5f96172fdaab66a268a53dccc6c7ffa87 This reverts commit 6681113633dc738ec95fe33104843a1e25acef3b which is commit bcc80dec91ee745b3d66f3e48f0ec2efdea97149 upstream. The dependant patch before this one caused build errors in the 6.6.y tree, so revert this for now so that we can fix them up properly. Reported-by: Ignat Korchagin <ignat@cloudflare.com> Link: https://lore.kernel.org/r/3DB3A6D3-0D3A-4682-B4FA-407B2D3263B2@cloudflare.com Reported-by: Lars Wendler <wendler.lars@web.de> Link: https://lore.kernel.org/r/20250110103328.0e3906a8@chagall.paradoxon.rec Reported-by: Chris Clayton <chris2553@googlemail.com> Link: https://lore.kernel.org/r/10c7be00-b1f8-4389-801b-fb2d0b22468d@googlemail.com Cc: Dexuan Cui <decui@microsoft.com> Cc: Naman Jain <namjain@linux.microsoft.com> Cc: Michael Kelley <mhklinux@outlook.com> Cc: Wei Liu <wei.liu@kernel.org> Cc: Sasha Levin <sashal@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
This reverts commit 6681113633dc738ec95fe33104843a1e25acef3b which is
commit bcc80dec91ee745b3d66f3e48f0ec2efdea97149 upstream.

The dependant patch before this one caused build errors in the 6.6.y
tree, so revert this for now so that we can fix them up properly.

Reported-by: Ignat Korchagin <ignat@cloudflare.com>
Link: https://lore.kernel.org/r/3DB3A6D3-0D3A-4682-B4FA-407B2D3263B2@cloudflare.com
Reported-by: Lars Wendler <wendler.lars@web.de>
Link: https://lore.kernel.org/r/20250110103328.0e3906a8@chagall.paradoxon.rec
Reported-by: Chris Clayton <chris2553@googlemail.com>
Link: https://lore.kernel.org/r/10c7be00-b1f8-4389-801b-fb2d0b22468d@googlemail.com
Cc: Dexuan Cui <decui@microsoft.com>
Cc: Naman Jain <namjain@linux.microsoft.com>
Cc: Michael Kelley <mhklinux@outlook.com>
Cc: Wei Liu <wei.liu@kernel.org>
Cc: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
scsi: hisi_sas: Remove redundant checks for automatic debugfs dump 2025-01-09T12:32:09+00:00 Yihang Li liyihang9@huawei.com 2024-01-22T06:25:45+00:00 9722973ad03833ec4f693883f7f353ef128eb4d6 commit 3f030550476566b12091687c70071d05ad433e0d upstream. In commit 63f0733d07ce ("scsi: hisi_sas: Allocate DFX memory during dump trigger"), the memory allocation time of the DFX is changed from device initialization to dump occurs, so .debugfs_itct is not a valid address and do not need to check. The parameter hisi_sas_debugfs_enable is enough to check whether automatic debugfs dump is triggered, so remove redunant checks. Fixes: 63f0733d07ce ("scsi: hisi_sas: Allocate DFX memory during dump trigger") Signed-off-by: Yihang Li <liyihang9@huawei.com> Signed-off-by: Xiang Chen <chenxiang66@hisilicon.com> Link: https://lore.kernel.org/r/1705904747-62186-3-git-send-email-chenxiang66@hisilicon.com Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 3f030550476566b12091687c70071d05ad433e0d upstream.

In commit 63f0733d07ce ("scsi: hisi_sas: Allocate DFX memory during dump
trigger"), the memory allocation time of the DFX is changed from device
initialization to dump occurs, so .debugfs_itct is not a valid address and
do not need to check.

The parameter hisi_sas_debugfs_enable is enough to check whether automatic
debugfs dump is triggered, so remove redunant checks.

Fixes: 63f0733d07ce ("scsi: hisi_sas: Allocate DFX memory during dump trigger")
Signed-off-by: Yihang Li <liyihang9@huawei.com>
Signed-off-by: Xiang Chen <chenxiang66@hisilicon.com>
Link: https://lore.kernel.org/r/1705904747-62186-3-git-send-email-chenxiang66@hisilicon.com
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
RDMA/bnxt_re: Fix max SGEs for the Work Request 2025-01-09T12:32:09+00:00 Kashyap Desai kashyap.desai@broadcom.com 2024-12-04T07:54:12+00:00 3de1b50f055dc2ca7072a526cdda21f691c22dd9 commit 79d330fbdffd8cee06d8bdf38d82cb62d8363a27 upstream. Gen P7 supports up to 13 SGEs for now. WQE software structure can hold only 6 now. Since the max send sge is reported as 13, the stack can give requests up to 13 SGEs. This is causing traffic failures and system crashes. Use the define for max SGE supported for variable size. This will work for both static and variable WQEs. Fixes: 227f51743b61 ("RDMA/bnxt_re: Fix the max WQE size for static WQE support") Signed-off-by: Kashyap Desai <kashyap.desai@broadcom.com> Signed-off-by: Selvin Xavier <selvin.xavier@broadcom.com> Link: https://patch.msgid.link/20241204075416.478431-2-kalesh-anakkur.purayil@broadcom.com Signed-off-by: Leon Romanovsky <leon@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 79d330fbdffd8cee06d8bdf38d82cb62d8363a27 upstream.

Gen P7 supports up to 13 SGEs for now. WQE software structure
can hold only 6 now. Since the max send sge is reported as
13, the stack can give requests up to 13 SGEs. This is causing
traffic failures and system crashes.

Use the define for max SGE supported for variable size. This
will work for both static and variable WQEs.

Fixes: 227f51743b61 ("RDMA/bnxt_re: Fix the max WQE size for static WQE support")
Signed-off-by: Kashyap Desai <kashyap.desai@broadcom.com>
Signed-off-by: Selvin Xavier <selvin.xavier@broadcom.com>
Link: https://patch.msgid.link/20241204075416.478431-2-kalesh-anakkur.purayil@broadcom.com
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
gve: guard XDP xmit NDO on existence of xdp queues 2025-01-09T12:32:08+00:00 Joshua Washington joshwash@google.com 2024-12-18T13:34:12+00:00 cbe9eb2c39d09f3c8574febcfa39d8c09d0c7cb5 commit ff7c2dea9dd1a436fc79d6273adffdcc4a7ffea3 upstream. In GVE, dedicated XDP queues only exist when an XDP program is installed and the interface is up. As such, the NDO XDP XMIT callback should return early if either of these conditions are false. In the case of no loaded XDP program, priv->num_xdp_queues=0 which can cause a divide-by-zero error, and in the case of interface down, num_xdp_queues remains untouched to persist XDP queue count for the next interface up, but the TX pointer itself would be NULL. The XDP xmit callback also needs to synchronize with a device transitioning from open to close. This synchronization will happen via the GVE_PRIV_FLAGS_NAPI_ENABLED bit along with a synchronize_net() call, which waits for any RCU critical sections at call-time to complete. Fixes: 39a7f4aa3e4a ("gve: Add XDP REDIRECT support for GQI-QPL format") Cc: stable@vger.kernel.org Signed-off-by: Joshua Washington <joshwash@google.com> Signed-off-by: Praveen Kaligineedi <pkaligineedi@google.com> Reviewed-by: Praveen Kaligineedi <pkaligineedi@google.com> Reviewed-by: Shailend Chand <shailend@google.com> Reviewed-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit ff7c2dea9dd1a436fc79d6273adffdcc4a7ffea3 upstream.

In GVE, dedicated XDP queues only exist when an XDP program is installed
and the interface is up. As such, the NDO XDP XMIT callback should
return early if either of these conditions are false.

In the case of no loaded XDP program, priv->num_xdp_queues=0 which can
cause a divide-by-zero error, and in the case of interface down,
num_xdp_queues remains untouched to persist XDP queue count for the next
interface up, but the TX pointer itself would be NULL.

The XDP xmit callback also needs to synchronize with a device
transitioning from open to close. This synchronization will happen via
the GVE_PRIV_FLAGS_NAPI_ENABLED bit along with a synchronize_net() call,
which waits for any RCU critical sections at call-time to complete.

Fixes: 39a7f4aa3e4a ("gve: Add XDP REDIRECT support for GQI-QPL format")
Cc: stable@vger.kernel.org
Signed-off-by: Joshua Washington <joshwash@google.com>
Signed-off-by: Praveen Kaligineedi <pkaligineedi@google.com>
Reviewed-by: Praveen Kaligineedi <pkaligineedi@google.com>
Reviewed-by: Shailend Chand <shailend@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
gve: guard XSK operations on the existence of queues 2025-01-09T12:32:08+00:00 Joshua Washington joshwash@google.com 2024-12-18T13:34:13+00:00 771d66f2bd8c4dba1286a9163ab982cecd825718 commit 40338d7987d810fcaa95c500b1068a52b08eec9b upstream. This patch predicates the enabling and disabling of XSK pools on the existence of queues. As it stands, if the interface is down, disabling or enabling XSK pools would result in a crash, as the RX queue pointer would be NULL. XSK pool registration will occur as part of the next interface up. Similarly, xsk_wakeup needs be guarded against queues disappearing while the function is executing, so a check against the GVE_PRIV_FLAGS_NAPI_ENABLED flag is added to synchronize with the disabling of the bit and the synchronize_net() in gve_turndown. Fixes: fd8e40321a12 ("gve: Add AF_XDP zero-copy support for GQI-QPL format") Cc: stable@vger.kernel.org Signed-off-by: Joshua Washington <joshwash@google.com> Signed-off-by: Praveen Kaligineedi <pkaligineedi@google.com> Reviewed-by: Praveen Kaligineedi <pkaligineedi@google.com> Reviewed-by: Shailend Chand <shailend@google.com> Reviewed-by: Willem de Bruijn <willemb@google.com> Reviewed-by: Larysa Zaremba <larysa.zaremba@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 40338d7987d810fcaa95c500b1068a52b08eec9b upstream.

This patch predicates the enabling and disabling of XSK pools on the
existence of queues. As it stands, if the interface is down, disabling
or enabling XSK pools would result in a crash, as the RX queue pointer
would be NULL. XSK pool registration will occur as part of the next
interface up.

Similarly, xsk_wakeup needs be guarded against queues disappearing
while the function is executing, so a check against the
GVE_PRIV_FLAGS_NAPI_ENABLED flag is added to synchronize with the
disabling of the bit and the synchronize_net() in gve_turndown.

Fixes: fd8e40321a12 ("gve: Add AF_XDP zero-copy support for GQI-QPL format")
Cc: stable@vger.kernel.org
Signed-off-by: Joshua Washington <joshwash@google.com>
Signed-off-by: Praveen Kaligineedi <pkaligineedi@google.com>
Reviewed-by: Praveen Kaligineedi <pkaligineedi@google.com>
Reviewed-by: Shailend Chand <shailend@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Reviewed-by: Larysa Zaremba <larysa.zaremba@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drm: adv7511: Fix use-after-free in adv7533_attach_dsi() 2025-01-09T12:32:08+00:00 Biju Das biju.das.jz@bp.renesas.com 2024-11-19T19:20:29+00:00 1f49aaf55652580ae63ab83d67211fe6a55d83dc commit 81adbd3ff21c1182e06aa02c6be0bfd9ea02d8e8 upstream. The host_node pointer was assigned and freed in adv7533_parse_dt(), and later, adv7533_attach_dsi() uses the same. Fix this use-after-free issue by dropping of_node_put() in adv7533_parse_dt() and calling of_node_put() in error path of probe() and also in the remove(). Fixes: 1e4d58cd7f88 ("drm/bridge: adv7533: Create a MIPI DSI device") Cc: stable@vger.kernel.org Reviewed-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com> Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com> Link: https://patchwork.freedesktop.org/patch/msgid/20241119192040.152657-2-biju.das.jz@bp.renesas.com Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 81adbd3ff21c1182e06aa02c6be0bfd9ea02d8e8 upstream.

The host_node pointer was assigned and freed in adv7533_parse_dt(), and
later, adv7533_attach_dsi() uses the same. Fix this use-after-free issue
by dropping of_node_put() in adv7533_parse_dt() and calling of_node_put()
in error path of probe() and also in the remove().

Fixes: 1e4d58cd7f88 ("drm/bridge: adv7533: Create a MIPI DSI device")
Cc: stable@vger.kernel.org
Reviewed-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20241119192040.152657-2-biju.das.jz@bp.renesas.com
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drm: adv7511: Drop dsi single lane support 2025-01-09T12:32:08+00:00 Biju Das biju.das.jz@bp.renesas.com 2024-11-19T19:20:31+00:00 7b977f8c26b65c7788da19a150434171c1df953d commit 79d67c499c3f886202a40c5cb27e747e4fa4d738 upstream. As per [1] and [2], ADV7535/7533 supports only 2-, 3-, or 4-lane. Drop unsupported 1-lane. [1] https://www.analog.com/media/en/technical-documentation/data-sheets/ADV7535.pdf [2] https://www.analog.com/media/en/technical-documentation/data-sheets/ADV7533.pdf Fixes: 1e4d58cd7f88 ("drm/bridge: adv7533: Create a MIPI DSI device") Reported-by: Hien Huynh <hien.huynh.px@renesas.com> Cc: stable@vger.kernel.org Reviewed-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com> Reviewed-by: Adam Ford <aford173@gmail.com> Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com> Link: https://patchwork.freedesktop.org/patch/msgid/20241119192040.152657-4-biju.das.jz@bp.renesas.com Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 79d67c499c3f886202a40c5cb27e747e4fa4d738 upstream.

As per [1] and [2], ADV7535/7533 supports only 2-, 3-, or 4-lane. Drop
unsupported 1-lane.

[1] https://www.analog.com/media/en/technical-documentation/data-sheets/ADV7535.pdf
[2] https://www.analog.com/media/en/technical-documentation/data-sheets/ADV7533.pdf

Fixes: 1e4d58cd7f88 ("drm/bridge: adv7533: Create a MIPI DSI device")
Reported-by: Hien Huynh <hien.huynh.px@renesas.com>
Cc: stable@vger.kernel.org
Reviewed-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Reviewed-by: Adam Ford <aford173@gmail.com>
Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20241119192040.152657-4-biju.das.jz@bp.renesas.com
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
sky2: Add device ID 11ab:4373 for Marvell 88E8075 2025-01-09T12:32:07+00:00 Pascal Hambourg pascal@plouf.fr.eu.org 2024-12-23T16:44:01+00:00 b32c3b748d29eb1fcc9463f903b3540dccd5c887 commit 03c8d0af2e409e15c16130b185e12b5efba0a6b9 upstream. A Marvell 88E8075 ethernet controller has this device ID instead of 11ab:4370 and works fine with the sky2 driver. Signed-off-by: Pascal Hambourg <pascal@plouf.fr.eu.org> Cc: stable@vger.kernel.org Link: https://patch.msgid.link/10165a62-99fb-4be6-8c64-84afd6234085@plouf.fr.eu.org Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 03c8d0af2e409e15c16130b185e12b5efba0a6b9 upstream.

A Marvell 88E8075 ethernet controller has this device ID instead of
11ab:4370 and works fine with the sky2 driver.

Signed-off-by: Pascal Hambourg <pascal@plouf.fr.eu.org>
Cc: stable@vger.kernel.org
Link: https://patch.msgid.link/10165a62-99fb-4be6-8c64-84afd6234085@plouf.fr.eu.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
pinctrl: mcp23s08: Fix sleeping in atomic context due to regmap locking 2025-01-09T12:32:07+00:00 Evgenii Shatokhin e.shatokhin@yadro.com 2024-12-09T07:46:59+00:00 8c6fd5803b988a5e78c9b9e42c70a936d7cfc6ec commit a37eecb705f33726f1fb7cd2a67e514a15dfe693 upstream. If a device uses MCP23xxx IO expander to receive IRQs, the following bug can happen: BUG: sleeping function called from invalid context at kernel/locking/mutex.c:283 in_atomic(): 1, irqs_disabled(): 1, non_block: 0, ... preempt_count: 1, expected: 0 ... Call Trace: ... __might_resched+0x104/0x10e __might_sleep+0x3e/0x62 mutex_lock+0x20/0x4c regmap_lock_mutex+0x10/0x18 regmap_update_bits_base+0x2c/0x66 mcp23s08_irq_set_type+0x1ae/0x1d6 __irq_set_trigger+0x56/0x172 __setup_irq+0x1e6/0x646 request_threaded_irq+0xb6/0x160 ... We observed the problem while experimenting with a touchscreen driver which used MCP23017 IO expander (I2C). The regmap in the pinctrl-mcp23s08 driver uses a mutex for protection from concurrent accesses, which is the default for regmaps without .fast_io, .disable_locking, etc. mcp23s08_irq_set_type() calls regmap_update_bits_base(), and the latter locks the mutex. However, __setup_irq() locks desc->lock spinlock before calling these functions. As a result, the system tries to lock the mutex whole holding the spinlock. It seems, the internal regmap locks are not needed in this driver at all. mcp->lock seems to protect the regmap from concurrent accesses already, except, probably, in mcp_pinconf_get/set. mcp23s08_irq_set_type() and mcp23s08_irq_mask/unmask() are called under chip_bus_lock(), which calls mcp23s08_irq_bus_lock(). The latter takes mcp->lock and enables regmap caching, so that the potentially slow I2C accesses are deferred until chip_bus_unlock(). The accesses to the regmap from mcp23s08_probe_one() do not need additional locking. In all remaining places where the regmap is accessed, except mcp_pinconf_get/set(), the driver already takes mcp->lock. This patch adds locking in mcp_pinconf_get/set() and disables internal locking in the regmap config. Among other things, it fixes the sleeping in atomic context described above. Fixes: 8f38910ba4f6 ("pinctrl: mcp23s08: switch to regmap caching") Cc: stable@vger.kernel.org Signed-off-by: Evgenii Shatokhin <e.shatokhin@yadro.com> Link: https://lore.kernel.org/20241209074659.1442898-1-e.shatokhin@yadro.com Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit a37eecb705f33726f1fb7cd2a67e514a15dfe693 upstream.

If a device uses MCP23xxx IO expander to receive IRQs, the following
bug can happen:

  BUG: sleeping function called from invalid context
    at kernel/locking/mutex.c:283
  in_atomic(): 1, irqs_disabled(): 1, non_block: 0, ...
  preempt_count: 1, expected: 0
  ...
  Call Trace:
  ...
  __might_resched+0x104/0x10e
  __might_sleep+0x3e/0x62
  mutex_lock+0x20/0x4c
  regmap_lock_mutex+0x10/0x18
  regmap_update_bits_base+0x2c/0x66
  mcp23s08_irq_set_type+0x1ae/0x1d6
  __irq_set_trigger+0x56/0x172
  __setup_irq+0x1e6/0x646
  request_threaded_irq+0xb6/0x160
  ...

We observed the problem while experimenting with a touchscreen driver which
used MCP23017 IO expander (I2C).

The regmap in the pinctrl-mcp23s08 driver uses a mutex for protection from
concurrent accesses, which is the default for regmaps without .fast_io,
.disable_locking, etc.

mcp23s08_irq_set_type() calls regmap_update_bits_base(), and the latter
locks the mutex.

However, __setup_irq() locks desc->lock spinlock before calling these
functions. As a result, the system tries to lock the mutex whole holding
the spinlock.

It seems, the internal regmap locks are not needed in this driver at all.
mcp->lock seems to protect the regmap from concurrent accesses already,
except, probably, in mcp_pinconf_get/set.

mcp23s08_irq_set_type() and mcp23s08_irq_mask/unmask() are called under
chip_bus_lock(), which calls mcp23s08_irq_bus_lock(). The latter takes
mcp->lock and enables regmap caching, so that the potentially slow I2C
accesses are deferred until chip_bus_unlock().

The accesses to the regmap from mcp23s08_probe_one() do not need additional
locking.

In all remaining places where the regmap is accessed, except
mcp_pinconf_get/set(), the driver already takes mcp->lock.

This patch adds locking in mcp_pinconf_get/set() and disables internal
locking in the regmap config. Among other things, it fixes the sleeping
in atomic context described above.

Fixes: 8f38910ba4f6 ("pinctrl: mcp23s08: switch to regmap caching")
Cc: stable@vger.kernel.org
Signed-off-by: Evgenii Shatokhin <e.shatokhin@yadro.com>
Link: https://lore.kernel.org/20241209074659.1442898-1-e.shatokhin@yadro.com
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>