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pwm: atmel-hlcdc: Fix frequency output being half of expected#6

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pwm: atmel-hlcdc: Fix frequency output being half of expected#6
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The atmel-hlcdc PWM driver generates an output frequency that is
exactly half of the value requested in the device tree. For example,
a request for 1000 Hz results in a 500 Hz output.

This is caused by an incorrect prescaler calculation. The driver's
formula for the clock divider did not match the hardware, which uses
a division factor of 2^(pres + 1). The driver was missing the "+1",
causing the output period to be doubled.

This patch corrects the calculation to 2^(pres + 1), aligning it
with the hardware's behavior and ensuring the generated frequency is
correct.

The atmel-hlcdc PWM driver generates an output frequency that is
exactly half of the value requested in the device tree. For example,
a request for 1000 Hz results in a 500 Hz output.

This is caused by an incorrect prescaler calculation. The driver's
formula for the clock divider did not match the hardware, which uses
a division factor of 2^(pres + 1). The driver was missing the "+1",
causing the output period to be doubled.

This patch corrects the calculation to `2^(pres + 1)`, aligning it
with the hardware's behavior and ensuring the generated frequency is
correct.
cristibirsan pushed a commit that referenced this pull request Feb 12, 2026
[ Upstream commit 2939203 ]

In the current implementation, the enetc_xdp_xmit() always transmits
redirected XDP frames even if the link is down, but the frames cannot
be transmitted from TX BD rings when the link is down, so the frames
are still kept in the TX BD rings. If the XDP program is uninstalled,
users will see the following warning logs.

fsl_enetc 0000:00:00.0 eno0: timeout for tx ring #6 clear

More worse, the TX BD ring cannot work properly anymore, because the
HW PIR and CIR are not equal after the re-initialization of the TX
BD ring. At this point, the BDs between CIR and PIR are invalid,
which will cause a hardware malfunction.

Another reason is that there is internal context in the ring prefetch
logic that will retain the state from the first incarnation of the ring
and continue prefetching from the stale location when we re-initialize
the ring. The internal context is only reset by an FLR. That is to say,
for LS1028A ENETC, software cannot set the HW CIR and PIR when
initializing the TX BD ring.

It does not make sense to transmit redirected XDP frames when the link is
down. Add a link status check to prevent transmission in this condition.
This fixes part of the issue, but more complex cases remain. For example,
the TX BD ring may still contain unsent frames when the link goes down.
Those situations require additional patches, which will build on this
one.

Fixes: 9d2b68c ("net: enetc: add support for XDP_REDIRECT")
Signed-off-by: Wei Fang <wei.fang@nxp.com>
Reviewed-by: Frank Li <Frank.Li@nxp.com>
Reviewed-by: Hariprasad Kelam <hkelam@marvell.com>
Reviewed-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Link: https://patch.msgid.link/20251211020919.121113-1-wei.fang@nxp.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
cristibirsan pushed a commit that referenced this pull request Feb 12, 2026
commit c943bfc upstream.

After a copy pair swap the block device's "device" symlink points to
the secondary CCW device, but the gendisk's parent remained the
primary, leaving /sys/block/<dasdx> under the wrong parent.

Move the gendisk to the secondary's device with device_move(), keeping
the sysfs topology consistent after the swap.

Fixes: 413862c ("s390/dasd: add copy pair swap capability")
Cc: stable@vger.kernel.org #6.1
Reviewed-by: Jan Hoeppner <hoeppner@linux.ibm.com>
Signed-off-by: Stefan Haberland <sth@linux.ibm.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
lranders pushed a commit to lranders/linux4microchip-linux that referenced this pull request Apr 27, 2026
[ Upstream commit d935187 ]

A potential circular locking dependency (ABBA deadlock) exists between
`ec_dev->lock` and the clock framework's `prepare_lock`.

The first order (A -> B) occurs when scp_ipi_send() is called while
`ec_dev->lock` is held (e.g., within cros_ec_cmd_xfer()):
1. cros_ec_cmd_xfer() acquires `ec_dev->lock` and calls scp_ipi_send().
2. scp_ipi_send() calls clk_prepare_enable(), which acquires
   `prepare_lock`.
See #0 in the following example calling trace.
(Lock Order: `ec_dev->lock` -> `prepare_lock`)

The reverse order (B -> A) is more complex and has been observed
(learned) by lockdep.  It involves the clock prepare operation
triggering power domain changes, which then propagates through sysfs
and power supply uevents, eventually calling back into the ChromeOS EC
driver and attempting to acquire `ec_dev->lock`:
1. Something calls clk_prepare(), which acquires `prepare_lock`.  It
   then triggers genpd operations like genpd_runtime_resume(), which
   takes `&genpd->mlock`.
2. Power domain changes can trigger regulator changes; regulator
   changes can then trigger device link changes; device link changes
   can then trigger sysfs changes.  Eventually, power_supply_uevent()
   is called.
3. This leads to calls like cros_usbpd_charger_get_prop(), which calls
   cros_ec_cmd_xfer_status(), which then attempts to acquire
   `ec_dev->lock`.
See linux4microchip#1 ~ linux4microchip#6 in the following example calling trace.
(Lock Order: `prepare_lock` -> `&genpd->mlock` -> ... -> `&ec_dev->lock`)

Move the clk_prepare()/clk_unprepare() operations for `scp->clk` to the
remoteproc prepare()/unprepare() callbacks.  This ensures `prepare_lock`
is only acquired in prepare()/unprepare() callbacks.  Since
`ec_dev->lock` is not involved in the callbacks, the dependency loop is
broken.

This means the clock is always "prepared" when the SCP is running.  The
prolonged "prepared time" for the clock should be acceptable as SCP is
designed to be a very power efficient processor.  The power consumption
impact can be negligible.

A simplified calling trace reported by lockdep:
> -> linux4microchip#6 (&ec_dev->lock)
>        cros_ec_cmd_xfer
>        cros_ec_cmd_xfer_status
>        cros_usbpd_charger_get_port_status
>        cros_usbpd_charger_get_prop
>        power_supply_get_property
>        power_supply_show_property
>        power_supply_uevent
>        dev_uevent
>        uevent_show
>        dev_attr_show
>        sysfs_kf_seq_show
>        kernfs_seq_show
> -> linux4microchip#5 (kn->active#2)
>        kernfs_drain
>        __kernfs_remove
>        kernfs_remove_by_name_ns
>        sysfs_remove_file_ns
>        device_del
>        __device_link_del
>        device_links_driver_bound
> -> linux4microchip#4 (device_links_lock)
>        device_link_remove
>        _regulator_put
>        regulator_put
> -> linux4microchip#3 (regulator_list_mutex)
>        regulator_lock_dependent
>        regulator_disable
>        scpsys_power_off
>        _genpd_power_off
>        genpd_power_off
> -> linux4microchip#2 (&genpd->mlock/1)
>        genpd_add_subdomain
>        pm_genpd_add_subdomain
>        scpsys_add_subdomain
>        scpsys_probe
> -> linux4microchip#1 (&genpd->mlock)
>        genpd_runtime_resume
>        __rpm_callback
>        rpm_callback
>        rpm_resume
>        __pm_runtime_resume
>        clk_core_prepare
>        clk_prepare
> -> #0 (prepare_lock)
>        clk_prepare
>        scp_ipi_send
>        scp_send_ipi
>        mtk_rpmsg_send
>        rpmsg_send
>        cros_ec_pkt_xfer_rpmsg

Signed-off-by: Tzung-Bi Shih <tzungbi@kernel.org>
Reviewed-by: Chen-Yu Tsai <wenst@chromium.org>
Tested-by: Chen-Yu Tsai <wenst@chromium.org>
Link: https://lore.kernel.org/r/20260112110755.2435899-1-tzungbi@kernel.org
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
lranders pushed a commit to lranders/linux4microchip-linux that referenced this pull request Apr 27, 2026
commit 1ac22c8 upstream.

This leak will cause a hang when tearing down the SCSI host. For example,
iscsid hangs with the following call trace:

[130120.652718] scsi_alloc_sdev: Allocation failure during SCSI scanning, some SCSI devices might not be configured

PID: 2528     TASK: ffff9d0408974e00  CPU: 3    COMMAND: "iscsid"
 #0 [ffffb5b9c134b9e0] __schedule at ffffffff860657d4
 linux4microchip#1 [ffffb5b9c134ba28] schedule at ffffffff86065c6f
 linux4microchip#2 [ffffb5b9c134ba40] schedule_timeout at ffffffff86069fb0
 linux4microchip#3 [ffffb5b9c134bab0] __wait_for_common at ffffffff8606674f
 linux4microchip#4 [ffffb5b9c134bb10] scsi_remove_host at ffffffff85bfe84b
 linux4microchip#5 [ffffb5b9c134bb30] iscsi_sw_tcp_session_destroy at ffffffffc03031c4 [iscsi_tcp]
 linux4microchip#6 [ffffb5b9c134bb48] iscsi_if_recv_msg at ffffffffc0292692 [scsi_transport_iscsi]
 linux4microchip#7 [ffffb5b9c134bb98] iscsi_if_rx at ffffffffc02929c2 [scsi_transport_iscsi]
 linux4microchip#8 [ffffb5b9c134bbf0] netlink_unicast at ffffffff85e551d6
 #9 [ffffb5b9c134bc38] netlink_sendmsg at ffffffff85e554ef

Fixes: 8fe4ce5 ("scsi: core: Fix a use-after-free")
Cc: stable@vger.kernel.org
Signed-off-by: Junxiao Bi <junxiao.bi@oracle.com>
Reviewed-by: Mike Christie <michael.christie@oracle.com>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Link: https://patch.msgid.link/20260223232728.93350-1-junxiao.bi@oracle.com
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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