linux-stable.git/drivers/tty, branch v6.2.13 Linux kernel stable tree serial: 8250: Prevent starting up DMA Rx on THRI interrupt 2023-04-13T15:02:47+00:00 Ilpo Järvinen ilpo.jarvinen@linux.intel.com 2023-03-17T10:30:34+00:00 f23850d7eb2996ee727b93bffc68f5ffb21f94c6 commit 90b8596ac46043e4a782d9111f5b285251b13756 upstream. Hans de Goede reported Bluetooth adapters (HCIs) connected over an UART connection failed due corrupted Rx payload. The problem was narrowed down to DMA Rx starting on UART_IIR_THRI interrupt. The problem occurs despite LSR having DR bit set, which is precondition for attempting to start DMA Rx in the first place. From a debug patch: [x.807834] 8250irq: iir=cc lsr+saved=60 received=0/15 ier=0f dma_t/rx/err=0/0/0 [x.808676] 8250irq: iir=c2 lsr+saved=61 received=0/0 ier=0f dma_t/rx/err=0/0/0 [x.808776] 8250irq: iir=cc lsr+saved=60 received=1/12 ier=0d dma_t/rx/err=0/1/0 [x.808870] Bluetooth: hci0: Frame reassembly failed (-84) In the debug snippet, received field indicates 1 byte was transferred over DMA and 12 bytes after that with the non-DMA Rx. The sole byte DMA handled was corrupted (gets zeroed) which leads to the HCI failure. This problem became apparent after commit e8ffbb71f783 ("serial: 8250: use THRE & __stop_tx also with DMA") changed Tx stop behavior. Tx stop is now triggered from a THRI interrupt. Despite that this problem looks like a HW bug, this fix is not adding UART_BUG_xx flag to the driver beucase it seems useful in general to avoid starting DMA when there are only a few bytes to transfer. Skipping DMA for small transfers avoids the extra overhead DMA incurs. Thus, don't setup DMA Rx on UART_IIR_THRI but leave it to a subsequent interrupt which has Rx a related IIR value. By returning false from handle_rx_dma(), the DMA vs non-DMA decision is postponed until either UART_IIR_RDI (FIFO threshold worth of bytes awaiting) or UART_IIR_TIMEOUT (inter-character timeout) triggers at a later time which allows better to discern whether the number of bytes warrants starting DMA or not. Reported-by: Hans de Goede <hdegoede@redhat.com> Tested-by: Hans de Goede <hdegoede@redhat.com> Fixes: e8ffbb71f783 ("serial: 8250: use THRE & __stop_tx also with DMA") Cc: stable@vger.kernel.org Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Acked-by: Hans de Goede <hdegoede@redhat.com> Link: https://lore.kernel.org/r/20230317103034.12881-1-ilpo.jarvinen@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 90b8596ac46043e4a782d9111f5b285251b13756 upstream.

Hans de Goede reported Bluetooth adapters (HCIs) connected over an UART
connection failed due corrupted Rx payload. The problem was narrowed
down to DMA Rx starting on UART_IIR_THRI interrupt. The problem occurs
despite LSR having DR bit set, which is precondition for attempting to
start DMA Rx in the first place.

From a debug patch:
[x.807834] 8250irq: iir=cc lsr+saved=60 received=0/15 ier=0f dma_t/rx/err=0/0/0
[x.808676] 8250irq: iir=c2 lsr+saved=61 received=0/0 ier=0f dma_t/rx/err=0/0/0
[x.808776] 8250irq: iir=cc lsr+saved=60 received=1/12 ier=0d dma_t/rx/err=0/1/0
[x.808870] Bluetooth: hci0: Frame reassembly failed (-84)

In the debug snippet, received field indicates 1 byte was transferred
over DMA and 12 bytes after that with the non-DMA Rx. The sole byte DMA
handled was corrupted (gets zeroed) which leads to the HCI failure.

This problem became apparent after commit e8ffbb71f783 ("serial: 8250:
use THRE & __stop_tx also with DMA") changed Tx stop behavior. Tx stop
is now triggered from a THRI interrupt.

Despite that this problem looks like a HW bug, this fix is not adding
UART_BUG_xx flag to the driver beucase it seems useful in general to
avoid starting DMA when there are only a few bytes to transfer.
Skipping DMA for small transfers avoids the extra overhead DMA incurs.

Thus, don't setup DMA Rx on UART_IIR_THRI but leave it to a subsequent
interrupt which has Rx a related IIR value.

By returning false from handle_rx_dma(), the DMA vs non-DMA decision is
postponed until either UART_IIR_RDI (FIFO threshold worth of bytes
awaiting) or UART_IIR_TIMEOUT (inter-character timeout) triggers at a
later time which allows better to discern whether the number of bytes
warrants starting DMA or not.

Reported-by: Hans de Goede <hdegoede@redhat.com>
Tested-by: Hans de Goede <hdegoede@redhat.com>
Fixes: e8ffbb71f783 ("serial: 8250: use THRE & __stop_tx also with DMA")
Cc: stable@vger.kernel.org
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Acked-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20230317103034.12881-1-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
tty: serial: fsl_lpuart: fix crash in lpuart_uport_is_active 2023-04-13T15:02:46+00:00 Sherry Sun sherry.sun@nxp.com 2023-03-23T11:09:23+00:00 f4341fbb9c4186f32c70b309c06bb8d7ec59807e commit 178e00f36f934a88682d96aa046c1f90cb6f83a7 upstream. For serdev framework, tty->dev is a NULL pointer, lpuart_uport_is_active calling device_may_wakeup() may cause kernel NULL pointer crash, so here add the NULL pointer check before using it. Fixes: 4f5cb8c5e915 ("tty: serial: fsl_lpuart: enable wakeup source for lpuart") Cc: stable <stable@kernel.org> Signed-off-by: Sherry Sun <sherry.sun@nxp.com> Link: https://lore.kernel.org/r/20230323110923.24581-1-sherry.sun@nxp.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 178e00f36f934a88682d96aa046c1f90cb6f83a7 upstream.

For serdev framework, tty->dev is a NULL pointer, lpuart_uport_is_active
calling device_may_wakeup() may cause kernel NULL pointer crash, so here
add the NULL pointer check before using it.

Fixes: 4f5cb8c5e915 ("tty: serial: fsl_lpuart: enable wakeup source for lpuart")
Cc: stable <stable@kernel.org>
Signed-off-by: Sherry Sun <sherry.sun@nxp.com>
Link: https://lore.kernel.org/r/20230323110923.24581-1-sherry.sun@nxp.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
tty: serial: fsl_lpuart: avoid checking for transfer complete when UARTCTRL_SBK is asserted in lpuart32_tx_empty 2023-04-13T15:02:46+00:00 Sherry Sun sherry.sun@nxp.com 2023-03-23T05:44:15+00:00 b4f4fc898c89c627695df8215e74f41d4e91504d commit 9425914f3de6febbd6250395f56c8279676d9c3c upstream. According to LPUART RM, Transmission Complete Flag becomes 0 if queuing a break character by writing 1 to CTRL[SBK], so here need to avoid checking for transmission complete when UARTCTRL_SBK is asserted, otherwise the lpuart32_tx_empty may never get TIOCSER_TEMT. Commit 2411fd94ceaa("tty: serial: fsl_lpuart: skip waiting for transmission complete when UARTCTRL_SBK is asserted") only fix it in lpuart32_set_termios(), here also fix it in lpuart32_tx_empty(). Fixes: 380c966c093e ("tty: serial: fsl_lpuart: add 32-bit register interface support") Cc: stable <stable@kernel.org> Signed-off-by: Sherry Sun <sherry.sun@nxp.com> Link: https://lore.kernel.org/r/20230323054415.20363-1-sherry.sun@nxp.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 9425914f3de6febbd6250395f56c8279676d9c3c upstream.

According to LPUART RM, Transmission Complete Flag becomes 0 if queuing
a break character by writing 1 to CTRL[SBK], so here need to avoid
checking for transmission complete when UARTCTRL_SBK is asserted,
otherwise the lpuart32_tx_empty may never get TIOCSER_TEMT.

Commit 2411fd94ceaa("tty: serial: fsl_lpuart: skip waiting for
transmission complete when UARTCTRL_SBK is asserted") only fix it in
lpuart32_set_termios(), here also fix it in lpuart32_tx_empty().

Fixes: 380c966c093e ("tty: serial: fsl_lpuart: add 32-bit register interface support")
Cc: stable <stable@kernel.org>
Signed-off-by: Sherry Sun <sherry.sun@nxp.com>
Link: https://lore.kernel.org/r/20230323054415.20363-1-sherry.sun@nxp.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
tty: serial: sh-sci: Fix Rx on RZ/G2L SCI 2023-04-13T15:02:46+00:00 Biju Das biju.das.jz@bp.renesas.com 2023-03-21T11:47:50+00:00 39bc6e89738134cd12b8320292221fc52ce2a489 commit f92ed0cd9328aed918ebb0ebb64d259eccbcc6e7 upstream. SCI IP on RZ/G2L alike SoCs do not need regshift compared to other SCI IPs on the SH platform. Currently, it does regshift and configuring Rx wrongly. Drop adding regshift for RZ/G2L alike SoCs. Fixes: dfc80387aefb ("serial: sh-sci: Compute the regshift value for SCI ports") Cc: stable@vger.kernel.org Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com> Link: https://lore.kernel.org/r/20230321114753.75038-3-biju.das.jz@bp.renesas.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit f92ed0cd9328aed918ebb0ebb64d259eccbcc6e7 upstream.

SCI IP on RZ/G2L alike SoCs do not need regshift compared to other SCI
IPs on the SH platform. Currently, it does regshift and configuring Rx
wrongly. Drop adding regshift for RZ/G2L alike SoCs.

Fixes: dfc80387aefb ("serial: sh-sci: Compute the regshift value for SCI ports")
Cc: stable@vger.kernel.org
Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
Link: https://lore.kernel.org/r/20230321114753.75038-3-biju.das.jz@bp.renesas.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
tty: serial: sh-sci: Fix transmit end interrupt handler 2023-04-13T15:02:46+00:00 Biju Das biju.das.jz@bp.renesas.com 2023-03-17T15:04:03+00:00 dc8dbe92b46521c1e555fc913e712e35e7b9fcc3 commit b43a18647f03c87e77d50d6fe74904b61b96323e upstream. The fourth interrupt on SCI port is transmit end interrupt compared to the break interrupt on other port types. So, shuffle the interrupts to fix the transmit end interrupt handler. Fixes: e1d0be616186 ("sh-sci: Add h8300 SCI") Cc: stable <stable@kernel.org> Suggested-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com> Link: https://lore.kernel.org/r/20230317150403.154094-1-biju.das.jz@bp.renesas.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit b43a18647f03c87e77d50d6fe74904b61b96323e upstream.

The fourth interrupt on SCI port is transmit end interrupt compared to
the break interrupt on other port types. So, shuffle the interrupts to fix
the transmit end interrupt handler.

Fixes: e1d0be616186 ("sh-sci: Add h8300 SCI")
Cc: stable <stable@kernel.org>
Suggested-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
Link: https://lore.kernel.org/r/20230317150403.154094-1-biju.das.jz@bp.renesas.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
hvc/xen: prevent concurrent accesses to the shared ring 2023-03-30T10:51:21+00:00 Roger Pau Monne roger.pau@citrix.com 2022-11-30T15:09:11+00:00 ae935d2d2ea51b01255c2f2abb5ccab8b685d281 [ Upstream commit 6214894f49a967c749ee6c07cb00f9cede748df4 ] The hvc machinery registers both a console and a tty device based on the hv ops provided by the specific implementation. Those two interfaces however have different locks, and there's no single locks that's shared between the tty and the console implementations, hence the driver needs to protect itself against concurrent accesses. Otherwise concurrent calls using the split interfaces are likely to corrupt the ring indexes, leaving the console unusable. Introduce a lock to xencons_info to serialize accesses to the shared ring. This is only required when using the shared memory console, concurrent accesses to the hypercall based console implementation are not an issue. Note the conditional logic in domU_read_console() is slightly modified so the notify_daemon() call can be done outside of the locked region: it's an hypercall and there's no need for it to be done with the lock held. Fixes: b536b4b96230 ('xen: use the hvc console infrastructure for Xen console') Signed-off-by: Roger Pau Monné <roger.pau@citrix.com> Reviewed-by: Juergen Gross <jgross@suse.com> Link: https://lore.kernel.org/r/20221130150919.13935-1-roger.pau@citrix.com Signed-off-by: Juergen Gross <jgross@suse.com> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 6214894f49a967c749ee6c07cb00f9cede748df4 ]

The hvc machinery registers both a console and a tty device based on
the hv ops provided by the specific implementation.  Those two
interfaces however have different locks, and there's no single locks
that's shared between the tty and the console implementations, hence
the driver needs to protect itself against concurrent accesses.
Otherwise concurrent calls using the split interfaces are likely to
corrupt the ring indexes, leaving the console unusable.

Introduce a lock to xencons_info to serialize accesses to the shared
ring.  This is only required when using the shared memory console,
concurrent accesses to the hypercall based console implementation are
not an issue.

Note the conditional logic in domU_read_console() is slightly modified
so the notify_daemon() call can be done outside of the locked region:
it's an hypercall and there's no need for it to be done with the lock
held.

Fixes: b536b4b96230 ('xen: use the hvc console infrastructure for Xen console')
Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Link: https://lore.kernel.org/r/20221130150919.13935-1-roger.pau@citrix.com
Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
serial: 8250: ASPEED_VUART: select REGMAP instead of depending on it 2023-03-22T12:37:58+00:00 Randy Dunlap rdunlap@infradead.org 2023-02-26T05:39:53+00:00 32f36bc91f9132879fb390c543985858a88888b2 commit f8086d1a65ac693e3fd863128352b4b11ee7324d upstream. REGMAP is a hidden (not user visible) symbol. Users cannot set it directly thru "make *config", so drivers should select it instead of depending on it if they need it. Consistently using "select" or "depends on" can also help reduce Kconfig circular dependency issues. Therefore, change the use of "depends on REGMAP" to "select REGMAP". Fixes: 8d310c9107a2 ("drivers/tty/serial/8250: Make Aspeed VUART SIRQ polarity configurable") Cc: stable <stable@kernel.org> Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Oskar Senft <osk@google.com> Cc: linux-serial@vger.kernel.org Link: https://lore.kernel.org/r/20230226053953.4681-9-rdunlap@infradead.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit f8086d1a65ac693e3fd863128352b4b11ee7324d upstream.

REGMAP is a hidden (not user visible) symbol. Users cannot set it
directly thru "make *config", so drivers should select it instead of
depending on it if they need it.

Consistently using "select" or "depends on" can also help reduce
Kconfig circular dependency issues.

Therefore, change the use of "depends on REGMAP" to "select REGMAP".

Fixes: 8d310c9107a2 ("drivers/tty/serial/8250: Make Aspeed VUART SIRQ polarity configurable")
Cc: stable <stable@kernel.org>
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Oskar Senft <osk@google.com>
Cc: linux-serial@vger.kernel.org
Link: https://lore.kernel.org/r/20230226053953.4681-9-rdunlap@infradead.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
serial: 8250_fsl: fix handle_irq locking 2023-03-22T12:37:57+00:00 Johan Hovold johan@kernel.org 2023-02-27T08:50:46+00:00 f0ff9d2e2d9f61467ec4838705dded40204429a2 commit 6e01f9a594ee0f69fb52cc8d11971612b4817f0b upstream. The 8250 handle_irq callback is not just called from the interrupt handler but also from a timer callback when polling (e.g. for ports without an interrupt line). Consequently the callback must explicitly disable interrupts to avoid a potential deadlock with another interrupt in polled mode. Fix up the two paths in the freescale callback that failed to re-enable interrupts when polling. Fixes: 853a9ae29e97 ("serial: 8250: fix handle_irq locking") Cc: stable@vger.kernel.org # 5.13 Reported-by: Dan Carpenter <error27@gmail.com> Link: https://lore.kernel.org/r/Y/xYzqp4ogmOF5t0@kili Signed-off-by: Johan Hovold <johan@kernel.org> Acked-by: Jiri Slaby <jirislaby@kernel.org> Link: https://lore.kernel.org/r/20230227085046.24282-1-johan@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 6e01f9a594ee0f69fb52cc8d11971612b4817f0b upstream.

The 8250 handle_irq callback is not just called from the interrupt
handler but also from a timer callback when polling (e.g. for ports
without an interrupt line). Consequently the callback must explicitly
disable interrupts to avoid a potential deadlock with another interrupt
in polled mode.

Fix up the two paths in the freescale callback that failed to re-enable
interrupts when polling.

Fixes: 853a9ae29e97 ("serial: 8250: fix handle_irq locking")
Cc: stable@vger.kernel.org	# 5.13
Reported-by: Dan Carpenter <error27@gmail.com>
Link: https://lore.kernel.org/r/Y/xYzqp4ogmOF5t0@kili
Signed-off-by: Johan Hovold <johan@kernel.org>
Acked-by: Jiri Slaby <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20230227085046.24282-1-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
serial: 8250_em: Fix UART port type 2023-03-22T12:37:57+00:00 Biju Das biju.das.jz@bp.renesas.com 2023-02-27T11:41:46+00:00 d3310e840ed05d587f548126e3421ceb40debcca commit 32e293be736b853f168cd065d9cbc1b0c69f545d upstream. As per HW manual for EMEV2 "R19UH0040EJ0400 Rev.4.00", the UART IP found on EMMA mobile SoC is Register-compatible with the general-purpose 16750 UART chip. Fix UART port type as 16750 and enable 64-bytes fifo support. Fixes: 22886ee96895 ("serial8250-em: Emma Mobile UART driver V2") Cc: stable@vger.kernel.org Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com> Link: https://lore.kernel.org/r/20230227114152.22265-2-biju.das.jz@bp.renesas.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 32e293be736b853f168cd065d9cbc1b0c69f545d upstream.

As per HW manual for  EMEV2 "R19UH0040EJ0400 Rev.4.00", the UART
IP found on EMMA mobile SoC is Register-compatible with the
general-purpose 16750 UART chip. Fix UART port type as 16750 and
enable 64-bytes fifo support.

Fixes: 22886ee96895 ("serial8250-em: Emma Mobile UART driver V2")
Cc: stable@vger.kernel.org
Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
Link: https://lore.kernel.org/r/20230227114152.22265-2-biju.das.jz@bp.renesas.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
tty: serial: fsl_lpuart: skip waiting for transmission complete when UARTCTRL_SBK is asserted 2023-03-22T12:37:57+00:00 Sherry Sun sherry.sun@nxp.com 2023-02-23T09:39:41+00:00 c5e655f4230f8a21f0412695a0ad6ada7fadac0a commit 2411fd94ceaa6e11326e95d6ebf876cbfed28d23 upstream. According to LPUART RM, Transmission Complete Flag becomes 0 if queuing a break character by writing 1 to CTRL[SBK], so here need to skip waiting for transmission complete when UARTCTRL_SBK is asserted, otherwise the kernel may stuck here. And actually set_termios() adds transmission completion waiting to avoid data loss or data breakage when changing the baud rate, but we don't need to worry about this when queuing break characters. Signed-off-by: Sherry Sun <sherry.sun@nxp.com> Cc: stable <stable@kernel.org> Link: https://lore.kernel.org/r/20230223093941.31790-1-sherry.sun@nxp.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 2411fd94ceaa6e11326e95d6ebf876cbfed28d23 upstream.

According to LPUART RM, Transmission Complete Flag becomes 0 if queuing
a break character by writing 1 to CTRL[SBK], so here need to skip
waiting for transmission complete when UARTCTRL_SBK is asserted,
otherwise the kernel may stuck here.
And actually set_termios() adds transmission completion waiting to avoid
data loss or data breakage when changing the baud rate, but we don't
need to worry about this when queuing break characters.

Signed-off-by: Sherry Sun <sherry.sun@nxp.com>
Cc: stable <stable@kernel.org>
Link: https://lore.kernel.org/r/20230223093941.31790-1-sherry.sun@nxp.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>