<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/drivers/tty/serial/8250, branch linux-5.7.y</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>serial: 8250_mtk: Fix high-speed baud rates clamping</title>
<updated>2020-07-29T08:19:57+00:00</updated>
<author>
<name>Serge Semin</name>
<email>Sergey.Semin@baikalelectronics.ru</email>
</author>
<published>2020-07-14T12:41:12+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=53d34574b575d8eb02d60ae92c149e3930bcd1e9'/>
<id>53d34574b575d8eb02d60ae92c149e3930bcd1e9</id>
<content type='text'>
commit 551e553f0d4ab623e2a6f424ab5834f9c7b5229c upstream.

Commit 7b668c064ec3 ("serial: 8250: Fix max baud limit in generic 8250
port") fixed limits of a baud rate setting for a generic 8250 port.
In other words since that commit the baud rate has been permitted to be
within [uartclk / 16 / UART_DIV_MAX; uartclk / 16], which is absolutely
normal for a standard 8250 UART port. But there are custom 8250 ports,
which provide extended baud rate limits. In particular the Mediatek 8250
port can work with baud rates up to "uartclk" speed.

Normally that and any other peculiarity is supposed to be handled in a
custom set_termios() callback implemented in the vendor-specific
8250-port glue-driver. Currently that is how it's done for the most of
the vendor-specific 8250 ports, but for some reason for Mediatek a
solution has been spread out to both the glue-driver and to the generic
8250-port code. Due to that a bug has been introduced, which permitted the
extended baud rate limit for all even for standard 8250-ports. The bug
has been fixed by the commit 7b668c064ec3 ("serial: 8250: Fix max baud
limit in generic 8250 port") by narrowing the baud rates limit back down to
the normal bounds. Unfortunately by doing so we also broke the
Mediatek-specific extended bauds feature.

A fix of the problem described above is twofold. First since we can't get
back the extended baud rate limits feature to the generic set_termios()
function and that method supports only a standard baud rates range, the
requested baud rate must be locally stored before calling it and then
restored back to the new termios structure after the generic set_termios()
finished its magic business. By doing so we still use the
serial8250_do_set_termios() method to set the LCR/MCR/FCR/etc. registers,
while the extended baud rate setting procedure will be performed later in
the custom Mediatek-specific set_termios() callback. Second since a true
baud rate is now fully calculated in the custom set_termios() method we
need to locally update the port timeout by calling the
uart_update_timeout() function. After the fixes described above are
implemented in the 8250_mtk.c driver, the Mediatek 8250-port should
get back to normally working with extended baud rates.

Link: https://lore.kernel.org/linux-serial/20200701211337.3027448-1-danielwinkler@google.com

Fixes: 7b668c064ec3 ("serial: 8250: Fix max baud limit in generic 8250 port")
Reported-by: Daniel Winkler &lt;danielwinkler@google.com&gt;
Signed-off-by: Serge Semin &lt;Sergey.Semin@baikalelectronics.ru&gt;
Cc: stable &lt;stable@vger.kernel.org&gt;
Tested-by: Claire Chang &lt;tientzu@chromium.org&gt;
Link: https://lore.kernel.org/r/20200714124113.20918-1-Sergey.Semin@baikalelectronics.ru
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 551e553f0d4ab623e2a6f424ab5834f9c7b5229c upstream.

Commit 7b668c064ec3 ("serial: 8250: Fix max baud limit in generic 8250
port") fixed limits of a baud rate setting for a generic 8250 port.
In other words since that commit the baud rate has been permitted to be
within [uartclk / 16 / UART_DIV_MAX; uartclk / 16], which is absolutely
normal for a standard 8250 UART port. But there are custom 8250 ports,
which provide extended baud rate limits. In particular the Mediatek 8250
port can work with baud rates up to "uartclk" speed.

Normally that and any other peculiarity is supposed to be handled in a
custom set_termios() callback implemented in the vendor-specific
8250-port glue-driver. Currently that is how it's done for the most of
the vendor-specific 8250 ports, but for some reason for Mediatek a
solution has been spread out to both the glue-driver and to the generic
8250-port code. Due to that a bug has been introduced, which permitted the
extended baud rate limit for all even for standard 8250-ports. The bug
has been fixed by the commit 7b668c064ec3 ("serial: 8250: Fix max baud
limit in generic 8250 port") by narrowing the baud rates limit back down to
the normal bounds. Unfortunately by doing so we also broke the
Mediatek-specific extended bauds feature.

A fix of the problem described above is twofold. First since we can't get
back the extended baud rate limits feature to the generic set_termios()
function and that method supports only a standard baud rates range, the
requested baud rate must be locally stored before calling it and then
restored back to the new termios structure after the generic set_termios()
finished its magic business. By doing so we still use the
serial8250_do_set_termios() method to set the LCR/MCR/FCR/etc. registers,
while the extended baud rate setting procedure will be performed later in
the custom Mediatek-specific set_termios() callback. Second since a true
baud rate is now fully calculated in the custom set_termios() method we
need to locally update the port timeout by calling the
uart_update_timeout() function. After the fixes described above are
implemented in the 8250_mtk.c driver, the Mediatek 8250-port should
get back to normally working with extended baud rates.

Link: https://lore.kernel.org/linux-serial/20200701211337.3027448-1-danielwinkler@google.com

Fixes: 7b668c064ec3 ("serial: 8250: Fix max baud limit in generic 8250 port")
Reported-by: Daniel Winkler &lt;danielwinkler@google.com&gt;
Signed-off-by: Serge Semin &lt;Sergey.Semin@baikalelectronics.ru&gt;
Cc: stable &lt;stable@vger.kernel.org&gt;
Tested-by: Claire Chang &lt;tientzu@chromium.org&gt;
Link: https://lore.kernel.org/r/20200714124113.20918-1-Sergey.Semin@baikalelectronics.ru
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>serial: 8250: fix null-ptr-deref in serial8250_start_tx()</title>
<updated>2020-07-29T08:19:57+00:00</updated>
<author>
<name>Yang Yingliang</name>
<email>yangyingliang@huawei.com</email>
</author>
<published>2020-07-21T14:38:52+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=eb710a1ac0b2c5d46917563b78ebef429b0e8738'/>
<id>eb710a1ac0b2c5d46917563b78ebef429b0e8738</id>
<content type='text'>
commit f4c23a140d80ef5e6d3d1f8f57007649014b60fa upstream.

I got null-ptr-deref in serial8250_start_tx():

[   78.114630] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000
[   78.123778] Mem abort info:
[   78.126560]   ESR = 0x86000007
[   78.129603]   EC = 0x21: IABT (current EL), IL = 32 bits
[   78.134891]   SET = 0, FnV = 0
[   78.137933]   EA = 0, S1PTW = 0
[   78.141064] user pgtable: 64k pages, 48-bit VAs, pgdp=00000027d41a8600
[   78.147562] [0000000000000000] pgd=00000027893f0003, p4d=00000027893f0003, pud=00000027893f0003, pmd=00000027c9a20003, pte=0000000000000000
[   78.160029] Internal error: Oops: 86000007 [#1] SMP
[   78.164886] Modules linked in: sunrpc vfat fat aes_ce_blk crypto_simd cryptd aes_ce_cipher crct10dif_ce ghash_ce sha2_ce sha256_arm64 sha1_ce ses enclosure sg sbsa_gwdt ipmi_ssif spi_dw_mmio sch_fq_codel vhost_net tun vhost vhost_iotlb tap ip_tables ext4 mbcache jbd2 ahci hisi_sas_v3_hw libahci hisi_sas_main libsas hns3 scsi_transport_sas hclge libata megaraid_sas ipmi_si hnae3 ipmi_devintf ipmi_msghandler br_netfilter bridge stp llc nvme nvme_core xt_sctp sctp libcrc32c dm_mod nbd
[   78.207383] CPU: 11 PID: 23258 Comm: null-ptr Not tainted 5.8.0-rc6+ #48
[   78.214056] Hardware name: Huawei TaiShan 2280 V2/BC82AMDC, BIOS 2280-V2 CS V3.B210.01 03/12/2020
[   78.222888] pstate: 80400089 (Nzcv daIf +PAN -UAO BTYPE=--)
[   78.228435] pc : 0x0
[   78.230618] lr : serial8250_start_tx+0x160/0x260
[   78.235215] sp : ffff800062eefb80
[   78.238517] x29: ffff800062eefb80 x28: 0000000000000fff
[   78.243807] x27: ffff800062eefd80 x26: ffff202fd83b3000
[   78.249098] x25: ffff800062eefd80 x24: ffff202fd83b3000
[   78.254388] x23: ffff002fc5e50be8 x22: 0000000000000002
[   78.259679] x21: 0000000000000001 x20: 0000000000000000
[   78.264969] x19: ffffa688827eecc8 x18: 0000000000000000
[   78.270259] x17: 0000000000000000 x16: 0000000000000000
[   78.275550] x15: ffffa68881bc67a8 x14: 00000000000002e6
[   78.280841] x13: ffffa68881bc67a8 x12: 000000000000c539
[   78.286131] x11: d37a6f4de9bd37a7 x10: ffffa68881cccff0
[   78.291421] x9 : ffffa68881bc6000 x8 : ffffa688819daa88
[   78.296711] x7 : ffffa688822a0f20 x6 : ffffa688819e0000
[   78.302002] x5 : ffff800062eef9d0 x4 : ffffa68881e707a8
[   78.307292] x3 : 0000000000000000 x2 : 0000000000000002
[   78.312582] x1 : 0000000000000001 x0 : ffffa688827eecc8
[   78.317873] Call trace:
[   78.320312]  0x0
[   78.322147]  __uart_start.isra.9+0x64/0x78
[   78.326229]  uart_start+0xb8/0x1c8
[   78.329620]  uart_flush_chars+0x24/0x30
[   78.333442]  n_tty_receive_buf_common+0x7b0/0xc30
[   78.338128]  n_tty_receive_buf+0x44/0x2c8
[   78.342122]  tty_ioctl+0x348/0x11f8
[   78.345599]  ksys_ioctl+0xd8/0xf8
[   78.348903]  __arm64_sys_ioctl+0x2c/0xc8
[   78.352812]  el0_svc_common.constprop.2+0x88/0x1b0
[   78.357583]  do_el0_svc+0x44/0xd0
[   78.360887]  el0_sync_handler+0x14c/0x1d0
[   78.364880]  el0_sync+0x140/0x180
[   78.368185] Code: bad PC value

SERIAL_PORT_DFNS is not defined on each arch, if it's not defined,
serial8250_set_defaults() won't be called in serial8250_isa_init_ports(),
so the p-&gt;serial_in pointer won't be initialized, and it leads a null-ptr-deref.
Fix this problem by calling serial8250_set_defaults() after init uart port.

Signed-off-by: Yang Yingliang &lt;yangyingliang@huawei.com&gt;
Cc: stable &lt;stable@vger.kernel.org&gt;
Link: https://lore.kernel.org/r/20200721143852.4058352-1-yangyingliang@huawei.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit f4c23a140d80ef5e6d3d1f8f57007649014b60fa upstream.

I got null-ptr-deref in serial8250_start_tx():

[   78.114630] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000
[   78.123778] Mem abort info:
[   78.126560]   ESR = 0x86000007
[   78.129603]   EC = 0x21: IABT (current EL), IL = 32 bits
[   78.134891]   SET = 0, FnV = 0
[   78.137933]   EA = 0, S1PTW = 0
[   78.141064] user pgtable: 64k pages, 48-bit VAs, pgdp=00000027d41a8600
[   78.147562] [0000000000000000] pgd=00000027893f0003, p4d=00000027893f0003, pud=00000027893f0003, pmd=00000027c9a20003, pte=0000000000000000
[   78.160029] Internal error: Oops: 86000007 [#1] SMP
[   78.164886] Modules linked in: sunrpc vfat fat aes_ce_blk crypto_simd cryptd aes_ce_cipher crct10dif_ce ghash_ce sha2_ce sha256_arm64 sha1_ce ses enclosure sg sbsa_gwdt ipmi_ssif spi_dw_mmio sch_fq_codel vhost_net tun vhost vhost_iotlb tap ip_tables ext4 mbcache jbd2 ahci hisi_sas_v3_hw libahci hisi_sas_main libsas hns3 scsi_transport_sas hclge libata megaraid_sas ipmi_si hnae3 ipmi_devintf ipmi_msghandler br_netfilter bridge stp llc nvme nvme_core xt_sctp sctp libcrc32c dm_mod nbd
[   78.207383] CPU: 11 PID: 23258 Comm: null-ptr Not tainted 5.8.0-rc6+ #48
[   78.214056] Hardware name: Huawei TaiShan 2280 V2/BC82AMDC, BIOS 2280-V2 CS V3.B210.01 03/12/2020
[   78.222888] pstate: 80400089 (Nzcv daIf +PAN -UAO BTYPE=--)
[   78.228435] pc : 0x0
[   78.230618] lr : serial8250_start_tx+0x160/0x260
[   78.235215] sp : ffff800062eefb80
[   78.238517] x29: ffff800062eefb80 x28: 0000000000000fff
[   78.243807] x27: ffff800062eefd80 x26: ffff202fd83b3000
[   78.249098] x25: ffff800062eefd80 x24: ffff202fd83b3000
[   78.254388] x23: ffff002fc5e50be8 x22: 0000000000000002
[   78.259679] x21: 0000000000000001 x20: 0000000000000000
[   78.264969] x19: ffffa688827eecc8 x18: 0000000000000000
[   78.270259] x17: 0000000000000000 x16: 0000000000000000
[   78.275550] x15: ffffa68881bc67a8 x14: 00000000000002e6
[   78.280841] x13: ffffa68881bc67a8 x12: 000000000000c539
[   78.286131] x11: d37a6f4de9bd37a7 x10: ffffa68881cccff0
[   78.291421] x9 : ffffa68881bc6000 x8 : ffffa688819daa88
[   78.296711] x7 : ffffa688822a0f20 x6 : ffffa688819e0000
[   78.302002] x5 : ffff800062eef9d0 x4 : ffffa68881e707a8
[   78.307292] x3 : 0000000000000000 x2 : 0000000000000002
[   78.312582] x1 : 0000000000000001 x0 : ffffa688827eecc8
[   78.317873] Call trace:
[   78.320312]  0x0
[   78.322147]  __uart_start.isra.9+0x64/0x78
[   78.326229]  uart_start+0xb8/0x1c8
[   78.329620]  uart_flush_chars+0x24/0x30
[   78.333442]  n_tty_receive_buf_common+0x7b0/0xc30
[   78.338128]  n_tty_receive_buf+0x44/0x2c8
[   78.342122]  tty_ioctl+0x348/0x11f8
[   78.345599]  ksys_ioctl+0xd8/0xf8
[   78.348903]  __arm64_sys_ioctl+0x2c/0xc8
[   78.352812]  el0_svc_common.constprop.2+0x88/0x1b0
[   78.357583]  do_el0_svc+0x44/0xd0
[   78.360887]  el0_sync_handler+0x14c/0x1d0
[   78.364880]  el0_sync+0x140/0x180
[   78.368185] Code: bad PC value

SERIAL_PORT_DFNS is not defined on each arch, if it's not defined,
serial8250_set_defaults() won't be called in serial8250_isa_init_ports(),
so the p-&gt;serial_in pointer won't be initialized, and it leads a null-ptr-deref.
Fix this problem by calling serial8250_set_defaults() after init uart port.

Signed-off-by: Yang Yingliang &lt;yangyingliang@huawei.com&gt;
Cc: stable &lt;stable@vger.kernel.org&gt;
Link: https://lore.kernel.org/r/20200721143852.4058352-1-yangyingliang@huawei.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>serial: exar: Fix GPIO configuration for Sealevel cards based on XR17V35X</title>
<updated>2020-07-29T08:19:48+00:00</updated>
<author>
<name>Matthew Howell</name>
<email>matthew.howell@sealevel.com</email>
</author>
<published>2020-07-22T20:11:24+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=16155138e82bebf86d8b0ed82df33ba8ef463f49'/>
<id>16155138e82bebf86d8b0ed82df33ba8ef463f49</id>
<content type='text'>
[ Upstream commit 5fdbe136ae19ab751daaa4d08d9a42f3e30d17f9 ]

Sealevel XR17V35X based devices are inoperable on kernel versions
4.11 and above due to a change in the GPIO preconfiguration introduced in
commit
7dea8165f1d. This patch fixes this by preconfiguring the GPIO on Sealevel
cards to the value (0x00) used prior to commit 7dea8165f1d

With GPIOs preconfigured as per commit 7dea8165f1d all ports on
Sealevel XR17V35X based devices become stuck in high impedance
mode, regardless of dip-switch or software configuration. This
causes the device to become effectively unusable. This patch (in
various forms) has been distributed to our customers and no issues
related to it have been reported.

Fixes: 7dea8165f1d6 ("serial: exar: Preconfigure xr17v35x MPIOs as output")
Signed-off-by: Matthew Howell &lt;matthew.howell@sealevel.com&gt;
Link: https://lore.kernel.org/r/alpine.DEB.2.21.2007221605270.13247@tstest-VirtualBox
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 5fdbe136ae19ab751daaa4d08d9a42f3e30d17f9 ]

Sealevel XR17V35X based devices are inoperable on kernel versions
4.11 and above due to a change in the GPIO preconfiguration introduced in
commit
7dea8165f1d. This patch fixes this by preconfiguring the GPIO on Sealevel
cards to the value (0x00) used prior to commit 7dea8165f1d

With GPIOs preconfigured as per commit 7dea8165f1d all ports on
Sealevel XR17V35X based devices become stuck in high impedance
mode, regardless of dip-switch or software configuration. This
causes the device to become effectively unusable. This patch (in
various forms) has been distributed to our customers and no issues
related to it have been reported.

Fixes: 7dea8165f1d6 ("serial: exar: Preconfigure xr17v35x MPIOs as output")
Signed-off-by: Matthew Howell &lt;matthew.howell@sealevel.com&gt;
Link: https://lore.kernel.org/r/alpine.DEB.2.21.2007221605270.13247@tstest-VirtualBox
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>serial: 8250: Fix max baud limit in generic 8250 port</title>
<updated>2020-06-24T15:48:22+00:00</updated>
<author>
<name>Serge Semin</name>
<email>Sergey.Semin@baikalelectronics.ru</email>
</author>
<published>2020-05-06T23:31:32+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=a0b87556acee782a45b73d1592e9e871d379b769'/>
<id>a0b87556acee782a45b73d1592e9e871d379b769</id>
<content type='text'>
[ Upstream commit 7b668c064ec33f3d687c3a413d05e355172e6c92 ]

Standard 8250 UART ports are designed in a way so they can communicate
with baud rates up to 1/16 of a reference frequency. It's expected from
most of the currently supported UART controllers. That's why the former
version of serial8250_get_baud_rate() method called uart_get_baud_rate()
with min and max baud rates passed as (port-&gt;uartclk / 16 / UART_DIV_MAX)
and ((port-&gt;uartclk + tolerance) / 16) respectively. Doing otherwise, like
it was suggested in commit ("serial: 8250_mtk: support big baud rate."),
caused acceptance of bauds, which was higher than the normal UART
controllers actually supported. As a result if some user-space program
requested to set a baud greater than (uartclk / 16) it would have been
permitted without truncation, but then serial8250_get_divisor(baud)
(which calls uart_get_divisor() to get the reference clock divisor) would
have returned a zero divisor. Setting zero divisor will cause an
unpredictable effect varying from chip to chip. In case of DW APB UART the
communications just stop.

Lets fix this problem by getting back the limitation of (uartclk +
tolerance) / 16 maximum baud supported by the generic 8250 port. Mediatek
8250 UART ports driver developer shouldn't have touched it in the first
place  notably seeing he already provided a custom version of set_termios()
callback in that glue-driver which took into account the extended baud
rate values and accordingly updated the standard and vendor-specific
divisor latch registers anyway.

Fixes: 81bb549fdf14 ("serial: 8250_mtk: support big baud rate.")
Signed-off-by: Serge Semin &lt;Sergey.Semin@baikalelectronics.ru&gt;
Cc: Alexey Malahov &lt;Alexey.Malahov@baikalelectronics.ru&gt;
Cc: Thomas Bogendoerfer &lt;tsbogend@alpha.franken.de&gt;
Cc: Paul Burton &lt;paulburton@kernel.org&gt;
Cc: Ralf Baechle &lt;ralf@linux-mips.org&gt;
Cc: Arnd Bergmann &lt;arnd@arndb.de&gt;
Cc: Long Cheng &lt;long.cheng@mediatek.com&gt;
Cc: Andy Shevchenko &lt;andriy.shevchenko@linux.intel.com&gt;
Cc: Maxime Ripard &lt;mripard@kernel.org&gt;
Cc: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Cc: Will Deacon &lt;will@kernel.org&gt;
Cc: Russell King &lt;linux@armlinux.org.uk&gt;
Cc: linux-mips@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-mediatek@lists.infradead.org
Link: https://lore.kernel.org/r/20200506233136.11842-2-Sergey.Semin@baikalelectronics.ru
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 7b668c064ec33f3d687c3a413d05e355172e6c92 ]

Standard 8250 UART ports are designed in a way so they can communicate
with baud rates up to 1/16 of a reference frequency. It's expected from
most of the currently supported UART controllers. That's why the former
version of serial8250_get_baud_rate() method called uart_get_baud_rate()
with min and max baud rates passed as (port-&gt;uartclk / 16 / UART_DIV_MAX)
and ((port-&gt;uartclk + tolerance) / 16) respectively. Doing otherwise, like
it was suggested in commit ("serial: 8250_mtk: support big baud rate."),
caused acceptance of bauds, which was higher than the normal UART
controllers actually supported. As a result if some user-space program
requested to set a baud greater than (uartclk / 16) it would have been
permitted without truncation, but then serial8250_get_divisor(baud)
(which calls uart_get_divisor() to get the reference clock divisor) would
have returned a zero divisor. Setting zero divisor will cause an
unpredictable effect varying from chip to chip. In case of DW APB UART the
communications just stop.

Lets fix this problem by getting back the limitation of (uartclk +
tolerance) / 16 maximum baud supported by the generic 8250 port. Mediatek
8250 UART ports driver developer shouldn't have touched it in the first
place  notably seeing he already provided a custom version of set_termios()
callback in that glue-driver which took into account the extended baud
rate values and accordingly updated the standard and vendor-specific
divisor latch registers anyway.

Fixes: 81bb549fdf14 ("serial: 8250_mtk: support big baud rate.")
Signed-off-by: Serge Semin &lt;Sergey.Semin@baikalelectronics.ru&gt;
Cc: Alexey Malahov &lt;Alexey.Malahov@baikalelectronics.ru&gt;
Cc: Thomas Bogendoerfer &lt;tsbogend@alpha.franken.de&gt;
Cc: Paul Burton &lt;paulburton@kernel.org&gt;
Cc: Ralf Baechle &lt;ralf@linux-mips.org&gt;
Cc: Arnd Bergmann &lt;arnd@arndb.de&gt;
Cc: Long Cheng &lt;long.cheng@mediatek.com&gt;
Cc: Andy Shevchenko &lt;andriy.shevchenko@linux.intel.com&gt;
Cc: Maxime Ripard &lt;mripard@kernel.org&gt;
Cc: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Cc: Will Deacon &lt;will@kernel.org&gt;
Cc: Russell King &lt;linux@armlinux.org.uk&gt;
Cc: linux-mips@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-mediatek@lists.infradead.org
Link: https://lore.kernel.org/r/20200506233136.11842-2-Sergey.Semin@baikalelectronics.ru
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>serial: 8250: Avoid error message on reprobe</title>
<updated>2020-06-22T07:33:01+00:00</updated>
<author>
<name>Lukas Wunner</name>
<email>lukas@wunner.de</email>
</author>
<published>2020-05-12T12:40:01+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=b799bed7f03ffe52aa390d51dd5bf88cecd67d4c'/>
<id>b799bed7f03ffe52aa390d51dd5bf88cecd67d4c</id>
<content type='text'>
commit e0a851fe6b9b619527bd928aa93caaddd003f70c upstream.

If the call to uart_add_one_port() in serial8250_register_8250_port()
fails, a half-initialized entry in the serial_8250ports[] array is left
behind.

A subsequent reprobe of the same serial port causes that entry to be
reused.  Because uart-&gt;port.dev is set, uart_remove_one_port() is called
for the half-initialized entry and bails out with an error message:

bcm2835-aux-uart 3f215040.serial: Removing wrong port: (null) != (ptrval)

The same happens on failure of mctrl_gpio_init() since commit
4a96895f74c9 ("tty/serial/8250: use mctrl_gpio helpers").

Fix by zeroing the uart-&gt;port.dev pointer in the probe error path.

The bug was introduced in v2.6.10 by historical commit befff6f5bf5f
("[SERIAL] Add new port registration/unregistration functions."):
https://git.kernel.org/tglx/history/c/befff6f5bf5f

The commit added an unconditional call to uart_remove_one_port() in
serial8250_register_port().  In v3.7, commit 835d844d1a28 ("8250_pnp:
do pnp probe before legacy probe") made that call conditional on
uart-&gt;port.dev which allows me to fix the issue by zeroing that pointer
in the error path.  Thus, the present commit will fix the problem as far
back as v3.7 whereas still older versions need to also cherry-pick
835d844d1a28.

Fixes: 835d844d1a28 ("8250_pnp: do pnp probe before legacy probe")
Signed-off-by: Lukas Wunner &lt;lukas@wunner.de&gt;
Cc: stable@vger.kernel.org # v2.6.10
Cc: stable@vger.kernel.org # v2.6.10: 835d844d1a28: 8250_pnp: do pnp probe before legacy
Reviewed-by: Andy Shevchenko &lt;andriy.shevchenko@linux.intel.com&gt;
Link: https://lore.kernel.org/r/b4a072013ee1a1d13ee06b4325afb19bda57ca1b.1589285873.git.lukas@wunner.de
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit e0a851fe6b9b619527bd928aa93caaddd003f70c upstream.

If the call to uart_add_one_port() in serial8250_register_8250_port()
fails, a half-initialized entry in the serial_8250ports[] array is left
behind.

A subsequent reprobe of the same serial port causes that entry to be
reused.  Because uart-&gt;port.dev is set, uart_remove_one_port() is called
for the half-initialized entry and bails out with an error message:

bcm2835-aux-uart 3f215040.serial: Removing wrong port: (null) != (ptrval)

The same happens on failure of mctrl_gpio_init() since commit
4a96895f74c9 ("tty/serial/8250: use mctrl_gpio helpers").

Fix by zeroing the uart-&gt;port.dev pointer in the probe error path.

The bug was introduced in v2.6.10 by historical commit befff6f5bf5f
("[SERIAL] Add new port registration/unregistration functions."):
https://git.kernel.org/tglx/history/c/befff6f5bf5f

The commit added an unconditional call to uart_remove_one_port() in
serial8250_register_port().  In v3.7, commit 835d844d1a28 ("8250_pnp:
do pnp probe before legacy probe") made that call conditional on
uart-&gt;port.dev which allows me to fix the issue by zeroing that pointer
in the error path.  Thus, the present commit will fix the problem as far
back as v3.7 whereas still older versions need to also cherry-pick
835d844d1a28.

Fixes: 835d844d1a28 ("8250_pnp: do pnp probe before legacy probe")
Signed-off-by: Lukas Wunner &lt;lukas@wunner.de&gt;
Cc: stable@vger.kernel.org # v2.6.10
Cc: stable@vger.kernel.org # v2.6.10: 835d844d1a28: 8250_pnp: do pnp probe before legacy
Reviewed-by: Andy Shevchenko &lt;andriy.shevchenko@linux.intel.com&gt;
Link: https://lore.kernel.org/r/b4a072013ee1a1d13ee06b4325afb19bda57ca1b.1589285873.git.lukas@wunner.de
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>serial: 8250_pci: Move Pericom IDs to pci_ids.h</title>
<updated>2020-06-22T07:32:59+00:00</updated>
<author>
<name>Kai-Heng Feng</name>
<email>kai.heng.feng@canonical.com</email>
</author>
<published>2020-05-08T06:53:40+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=e552506849dc09f20a1bdcafa9d9cca88a7788c0'/>
<id>e552506849dc09f20a1bdcafa9d9cca88a7788c0</id>
<content type='text'>
[ Upstream commit 62a7f3009a460001eb46984395280dd900bc4ef4 ]

Move the IDs to pci_ids.h so it can be used by next patch.

Link: https://lore.kernel.org/r/20200508065343.32751-1-kai.heng.feng@canonical.com
Signed-off-by: Kai-Heng Feng &lt;kai.heng.feng@canonical.com&gt;
Signed-off-by: Bjorn Helgaas &lt;bhelgaas@google.com&gt;
Acked-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Cc: stable@vger.kernel.org
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 62a7f3009a460001eb46984395280dd900bc4ef4 ]

Move the IDs to pci_ids.h so it can be used by next patch.

Link: https://lore.kernel.org/r/20200508065343.32751-1-kai.heng.feng@canonical.com
Signed-off-by: Kai-Heng Feng &lt;kai.heng.feng@canonical.com&gt;
Signed-off-by: Bjorn Helgaas &lt;bhelgaas@google.com&gt;
Acked-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Cc: stable@vger.kernel.org
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>serial: 8250: Enable 16550A variants by default on non-x86</title>
<updated>2020-06-10T18:21:44+00:00</updated>
<author>
<name>Josh Triplett</name>
<email>josh@joshtriplett.org</email>
</author>
<published>2020-05-26T16:13:57+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=740049da812ce7d935c985997bc2341993586ed9'/>
<id>740049da812ce7d935c985997bc2341993586ed9</id>
<content type='text'>
commit 15a3f03d5ec0118f1e5db3fc1018686e72744e37 upstream.

Some embedded devices still use these serial ports; make sure they're
still enabled by default on architectures more likely to have them, to
avoid rendering someone's console unavailable.

Reported-by: Vladimir Oltean &lt;vladimir.oltean@nxp.com&gt;
Reported-by: Maxim Kochetkov &lt;fido_max@inbox.ru&gt;
Fixes: dc56ecb81a0a ("serial: 8250: Support disabling mdelay-filled probes of 16550A variants")
Cc: stable &lt;stable@vger.kernel.org&gt;
Signed-off-by: Josh Triplett &lt;josh@joshtriplett.org&gt;
Link: https://lore.kernel.org/r/a20b5fb7dd295cfb48160eecf4bdebd76332d67d.1590509426.git.josh@joshtriplett.org
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 15a3f03d5ec0118f1e5db3fc1018686e72744e37 upstream.

Some embedded devices still use these serial ports; make sure they're
still enabled by default on architectures more likely to have them, to
avoid rendering someone's console unavailable.

Reported-by: Vladimir Oltean &lt;vladimir.oltean@nxp.com&gt;
Reported-by: Maxim Kochetkov &lt;fido_max@inbox.ru&gt;
Fixes: dc56ecb81a0a ("serial: 8250: Support disabling mdelay-filled probes of 16550A variants")
Cc: stable &lt;stable@vger.kernel.org&gt;
Signed-off-by: Josh Triplett &lt;josh@joshtriplett.org&gt;
Link: https://lore.kernel.org/r/a20b5fb7dd295cfb48160eecf4bdebd76332d67d.1590509426.git.josh@joshtriplett.org
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'tty-5.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty</title>
<updated>2020-03-31T23:18:55+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2020-03-31T23:18:55+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=1f944f976d7ef8a29d1ad296253d3a9387c58e62'/>
<id>1f944f976d7ef8a29d1ad296253d3a9387c58e62</id>
<content type='text'>
Pull tty/serial updates from Greg KH:
 "Here is the big set of TTY / Serial patches for 5.7-rc1

  Lots of console fixups and reworking in here, serial core tweaks
  (doesn't that ever get old, why are we still creating new serial
  devices?), serial driver updates, line-protocol driver updates, and
  some vt cleanups and fixes included in here as well.

  All have been in linux-next with no reported issues"

* tag 'tty-5.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (161 commits)
  serial: 8250: Optimize irq enable after console write
  serial: 8250: Fix rs485 delay after console write
  vt: vt_ioctl: fix use-after-free in vt_in_use()
  vt: vt_ioctl: fix VT_DISALLOCATE freeing in-use virtual console
  tty: serial: make SERIAL_SPRD depend on COMMON_CLK
  tty: serial: fsl_lpuart: fix return value checking
  tty: serial: fsl_lpuart: move dma_request_chan()
  ARM: dts: tango4: Make /serial compatible with ns16550a
  ARM: dts: mmp*: Make the serial ports compatible with xscale-uart
  ARM: dts: mmp*: Fix serial port names
  ARM: dts: mmp2-brownstone: Don't redeclare phandle references
  ARM: dts: pxa*: Make the serial ports compatible with xscale-uart
  ARM: dts: pxa*: Fix serial port names
  ARM: dts: pxa*: Don't redeclare phandle references
  serial: omap: drop unused dt-bindings header
  serial: 8250: 8250_omap: Add DMA support for UARTs on K3 SoCs
  serial: 8250: 8250_omap: Work around errata causing spurious IRQs with DMA
  serial: 8250: 8250_omap: Extend driver data to pass FIFO trigger info
  serial: 8250: 8250_omap: Move locking out from __dma_rx_do_complete()
  serial: 8250: 8250_omap: Account for data in flight during DMA teardown
  ...
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull tty/serial updates from Greg KH:
 "Here is the big set of TTY / Serial patches for 5.7-rc1

  Lots of console fixups and reworking in here, serial core tweaks
  (doesn't that ever get old, why are we still creating new serial
  devices?), serial driver updates, line-protocol driver updates, and
  some vt cleanups and fixes included in here as well.

  All have been in linux-next with no reported issues"

* tag 'tty-5.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (161 commits)
  serial: 8250: Optimize irq enable after console write
  serial: 8250: Fix rs485 delay after console write
  vt: vt_ioctl: fix use-after-free in vt_in_use()
  vt: vt_ioctl: fix VT_DISALLOCATE freeing in-use virtual console
  tty: serial: make SERIAL_SPRD depend on COMMON_CLK
  tty: serial: fsl_lpuart: fix return value checking
  tty: serial: fsl_lpuart: move dma_request_chan()
  ARM: dts: tango4: Make /serial compatible with ns16550a
  ARM: dts: mmp*: Make the serial ports compatible with xscale-uart
  ARM: dts: mmp*: Fix serial port names
  ARM: dts: mmp2-brownstone: Don't redeclare phandle references
  ARM: dts: pxa*: Make the serial ports compatible with xscale-uart
  ARM: dts: pxa*: Fix serial port names
  ARM: dts: pxa*: Don't redeclare phandle references
  serial: omap: drop unused dt-bindings header
  serial: 8250: 8250_omap: Add DMA support for UARTs on K3 SoCs
  serial: 8250: 8250_omap: Work around errata causing spurious IRQs with DMA
  serial: 8250: 8250_omap: Extend driver data to pass FIFO trigger info
  serial: 8250: 8250_omap: Move locking out from __dma_rx_do_complete()
  serial: 8250: 8250_omap: Account for data in flight during DMA teardown
  ...
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge branch 'pm-qos'</title>
<updated>2020-03-30T12:45:57+00:00</updated>
<author>
<name>Rafael J. Wysocki</name>
<email>rafael.j.wysocki@intel.com</email>
</author>
<published>2020-03-30T12:45:57+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=8f1073ed8c18353ff2263294b243a315a71e9d48'/>
<id>8f1073ed8c18353ff2263294b243a315a71e9d48</id>
<content type='text'>
* pm-qos: (30 commits)
  PM: QoS: annotate data races in pm_qos_*_value()
  Documentation: power: fix pm_qos_interface.rst format warning
  PM: QoS: Make CPU latency QoS depend on CONFIG_CPU_IDLE
  Documentation: PM: QoS: Update to reflect previous code changes
  PM: QoS: Update file information comments
  PM: QoS: Drop PM_QOS_CPU_DMA_LATENCY and rename related functions
  sound: Call cpu_latency_qos_*() instead of pm_qos_*()
  drivers: usb: Call cpu_latency_qos_*() instead of pm_qos_*()
  drivers: tty: Call cpu_latency_qos_*() instead of pm_qos_*()
  drivers: spi: Call cpu_latency_qos_*() instead of pm_qos_*()
  drivers: net: Call cpu_latency_qos_*() instead of pm_qos_*()
  drivers: mmc: Call cpu_latency_qos_*() instead of pm_qos_*()
  drivers: media: Call cpu_latency_qos_*() instead of pm_qos_*()
  drivers: hsi: Call cpu_latency_qos_*() instead of pm_qos_*()
  drm: i915: Call cpu_latency_qos_*() instead of pm_qos_*()
  x86: platform: iosf_mbi: Call cpu_latency_qos_*() instead of pm_qos_*()
  cpuidle: Call cpu_latency_qos_limit() instead of pm_qos_request()
  PM: QoS: Add CPU latency QoS API wrappers
  PM: QoS: Adjust pm_qos_request() signature and reorder pm_qos.h
  PM: QoS: Simplify definitions of CPU latency QoS trace events
  ...
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
* pm-qos: (30 commits)
  PM: QoS: annotate data races in pm_qos_*_value()
  Documentation: power: fix pm_qos_interface.rst format warning
  PM: QoS: Make CPU latency QoS depend on CONFIG_CPU_IDLE
  Documentation: PM: QoS: Update to reflect previous code changes
  PM: QoS: Update file information comments
  PM: QoS: Drop PM_QOS_CPU_DMA_LATENCY and rename related functions
  sound: Call cpu_latency_qos_*() instead of pm_qos_*()
  drivers: usb: Call cpu_latency_qos_*() instead of pm_qos_*()
  drivers: tty: Call cpu_latency_qos_*() instead of pm_qos_*()
  drivers: spi: Call cpu_latency_qos_*() instead of pm_qos_*()
  drivers: net: Call cpu_latency_qos_*() instead of pm_qos_*()
  drivers: mmc: Call cpu_latency_qos_*() instead of pm_qos_*()
  drivers: media: Call cpu_latency_qos_*() instead of pm_qos_*()
  drivers: hsi: Call cpu_latency_qos_*() instead of pm_qos_*()
  drm: i915: Call cpu_latency_qos_*() instead of pm_qos_*()
  x86: platform: iosf_mbi: Call cpu_latency_qos_*() instead of pm_qos_*()
  cpuidle: Call cpu_latency_qos_limit() instead of pm_qos_request()
  PM: QoS: Add CPU latency QoS API wrappers
  PM: QoS: Adjust pm_qos_request() signature and reorder pm_qos.h
  PM: QoS: Simplify definitions of CPU latency QoS trace events
  ...
</pre>
</div>
</content>
</entry>
<entry>
<title>serial: 8250: Optimize irq enable after console write</title>
<updated>2020-03-27T14:45:54+00:00</updated>
<author>
<name>Lukas Wunner</name>
<email>lukas@wunner.de</email>
</author>
<published>2020-03-27T14:38:16+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=8d5b305484e8a3216eeb700ed6c6de870306adbd'/>
<id>8d5b305484e8a3216eeb700ed6c6de870306adbd</id>
<content type='text'>
Commit 7f9803072ff6 ("serial: 8250: Support console on software emulated
rs485 ports") amended serial8250_console_write() with rs485 support, but
positioned the invocation of -&gt;rs485_stop_tx() after re-enablement of
interrupts.  The irq handler and -&gt;console_write() are serialized with
the port spinlock, so no problem there, but due to the rs485 delay, the
irq handler may unnecessarily spin for a while.  Avoid that by moving
-&gt;rs485_stop_tx() before re-enablement of interrupts, which also mirrors
the order at the beginning of serial8250_console_write().

Signed-off-by: Lukas Wunner &lt;lukas@wunner.de&gt;
Link: https://lore.kernel.org/r/019839cb1f61b01210b6ff9ac9f9079ca77f8411.1585319447.git.lukas@wunner.de
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Commit 7f9803072ff6 ("serial: 8250: Support console on software emulated
rs485 ports") amended serial8250_console_write() with rs485 support, but
positioned the invocation of -&gt;rs485_stop_tx() after re-enablement of
interrupts.  The irq handler and -&gt;console_write() are serialized with
the port spinlock, so no problem there, but due to the rs485 delay, the
irq handler may unnecessarily spin for a while.  Avoid that by moving
-&gt;rs485_stop_tx() before re-enablement of interrupts, which also mirrors
the order at the beginning of serial8250_console_write().

Signed-off-by: Lukas Wunner &lt;lukas@wunner.de&gt;
Link: https://lore.kernel.org/r/019839cb1f61b01210b6ff9ac9f9079ca77f8411.1585319447.git.lukas@wunner.de
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
</feed>
