5.10.2-rc1 review

This is the start of the stable review cycle for the 5.10.2 release. There are 16 patches in this series, all will be posted as a response to this one. If anyone has any issues with these being applied, please let me know.

Responses should be made by Mon, 21 Dec 2020 12:53:29 +0000. Anything received after that time might be too late.

The whole patch series can be found in one patch at:

	https://www.kernel.org/pub/linux/kernel/v5.x/stable-review/patch-5.10.2-rc1.gz

or in the git tree and branch at:
git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable-rc.git linux-5.10.y
and the diffstat can be found below.

thanks,

greg k-h

-------------
Pseudo-Shortlog of commits:

Greg Kroah-Hartman <[email protected]>

    Linux 5.10.2-rc1

Alexander Sverdlin <[email protected]>
serial: 8250_omap: Avoid FIFO corruption caused by MDR1 access

Takashi Iwai <[email protected]>
ALSA: pcm: oss: Fix potential out-of-bounds shift

Thomas Gleixner <[email protected]>
USB: sisusbvga: Make console support depend on BROKEN

Oliver Neukum <[email protected]>
USB: UAS: introduce a quirk to set no_write_same

Mika Westerberg <[email protected]>
xhci-pci: Allow host runtime PM as default for Intel Maple Ridge xHCI

Hans de Goede <[email protected]>
xhci-pci: Allow host runtime PM as default for Intel Alpine Ridge LP

Tejas Joglekar <[email protected]>
usb: xhci: Set quirk for XHCI_SG_TRB_CACHE_SIZE_QUIRK

Li Jun <[email protected]>
xhci: Give USB2 ports time to enter U3 in bus suspend

Takashi Iwai <[email protected]>
ALSA: usb-audio: Fix control 'access overflow' errors from chmap

Takashi Iwai <[email protected]>
ALSA: usb-audio: Fix potential out-of-bounds shift

Oliver Neukum <[email protected]>
USB: add RESET_RESUME quirk for Snapscan 1212

Bui Quang Minh <[email protected]>
USB: dummy-hcd: Fix uninitialized array use in init()

Alan Stern <[email protected]>
USB: legotower: fix logical error in recent commit

Steven Rostedt (VMware) <[email protected]>
ktest.pl: Fix the logic for truncating the size of the log file for email

Steven Rostedt (VMware) <[email protected]>
ktest.pl: If size of log is too big to email, email error message

Peilin Ye <[email protected]>
ptrace: Prevent kernel-infoleak in ptrace_get_syscall_info()

-------------

Diffstat:

 Documentation/admin-guide/kernel-parameters.txt |  1 +
 Makefile                                        |  4 ++--
 drivers/tty/serial/8250/8250_omap.c             |  5 -----
 drivers/usb/core/quirks.c                       |  3 +++
 drivers/usb/gadget/udc/dummy_hcd.c              |  2 +-
 drivers/usb/host/xhci-hub.c                     |  4 ++++
 drivers/usb/host/xhci-pci.c                     |  6 +++++-
 drivers/usb/host/xhci-plat.c                    |  3 +++
 drivers/usb/host/xhci.h                         |  1 +
 drivers/usb/misc/legousbtower.c                 |  2 +-
 drivers/usb/misc/sisusbvga/Kconfig              |  2 +-
 drivers/usb/storage/uas.c                       |  3 +++
 drivers/usb/storage/unusual_uas.h               |  7 +++++--
 drivers/usb/storage/usb.c                       |  3 +++
 include/linux/usb_usual.h                       |  2 ++
 include/uapi/linux/ptrace.h                     |  3 ++-
 sound/core/oss/pcm_oss.c                        |  6 +++++-
 sound/usb/format.c                              |  2 ++
 sound/usb/stream.c                              |  6 +++---
 tools/testing/ktest/ktest.pl                    | 20 ++++++++++++--------
 20 files changed, 59 insertions(+), 26 deletions(-)

From: Peilin Ye <[email protected]>

commit 0032ce0f85a269a006e91277be5fdbc05fad8426 upstream.

ptrace_get_syscall_info() is potentially copying uninitialized stack memory to userspace, since the compiler may leave a 3-byte hole near the beginning of info. Fix it by adding a padding field to struct ptrace_syscall_info.

---
 include/uapi/linux/ptrace.h |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

@@ -81,7 +81,8 @@ struct seccomp_metadata {
 
 struct ptrace_syscall_info {
 	__u8 op;	/* PTRACE_SYSCALL_INFO_* */
-	__u32 arch __attribute__((__aligned__(sizeof(__u32))));
+	__u8 pad[3];
+	__u32 arch;
 	__u64 instruction_pointer;
 	__u64 stack_pointer;
 	union {

From: Steven Rostedt (VMware) <[email protected]>

commit 8cd6bc0359deebd8500e6de95899a8a78d3ec4ba upstream.

If the size of the error log is too big to send via email, and the sending fails, it wont email any result. This can be confusing for the user who is waiting for an email on the completion of the tests.

If it fails to send email, then try again without the log file stating that it failed to send an email. Obviously this will not be of use if the sending of email failed for some other reasons, but it will at least give the user some information when it fails for the most common reason.

---
 tools/testing/ktest/ktest.pl |    7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

@@ -4253,7 +4253,12 @@ sub do_send_mail {
     $mail_command =~ s/\$SUBJECT/$subject/g;
     $mail_command =~ s/\$MESSAGE/$message/g;
 
-    run_command $mail_command;
+    my $ret = run_command $mail_command;
+    if (!$ret && defined($file)) {
+	# try again without the file
+	$message .= "\n\n*** FAILED TO SEND LOG ***\n\n";
+	do_send_email($subject, $message);
+    }
 }
 
 sub send_email {

From: Steven Rostedt (VMware) <[email protected]>

commit 170f4869e66275f498ae4736106fb54c0fdcd036 upstream.

The logic for truncating the log file for emailing based on the MAIL_MAX_SIZE option is confusing and incorrect. Simplify it and have the tail of the log file truncated to the max size specified in the config.

---
 tools/testing/ktest/ktest.pl |   13 ++++++-------
 1 file changed, 6 insertions(+), 7 deletions(-)

@@ -1499,17 +1499,16 @@ sub dodie {
 	my $log_file;
 
 	if (defined($opt{"LOG_FILE"})) {
-	    my $whence = 0; # beginning of file
-	    my $pos = $test_log_start;
+	    my $whence = 2; # End of file
+	    my $log_size = tell LOG;
+	    my $size = $log_size - $test_log_start;
 
 	    if (defined($mail_max_size)) {
-		my $log_size = tell LOG;
-		$log_size -= $test_log_start;
-		if ($log_size > $mail_max_size) {
-		    $whence = 2; # end of file
-		    $pos = - $mail_max_size;
+		if ($size > $mail_max_size) {
+		    $size = $mail_max_size;
 		}
 	    }
+	    my $pos = - $size;
 	    $log_file = "$tmpdir/log";
 	    open (L, "$opt{LOG_FILE}") or die "Can't open $opt{LOG_FILE} to read)";
 	    open (O, "> $tmpdir/log") or die "Can't open $tmpdir/log\n";

From: Alan Stern <[email protected]>

commit b175d273d4e4100b66e68f0675fef7a3c07a7957 upstream.

Commit d9f0d82f06c6 ("USB: legousbtower: use usb_control_msg_recv()") contained an elementary logical error. The check of the return code from the new usb_control_msg_recv() function was inverted.

---
 drivers/usb/misc/legousbtower.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

@@ -797,7 +797,7 @@ static int tower_probe(struct usb_interf
 				      &get_version_reply,
 				      sizeof(get_version_reply),
 				      1000, GFP_KERNEL);
-	if (!result) {
+	if (result) {
 		dev_err(idev, "get version request failed: %d\n", result);
 		retval = result;
 		goto error;

From: Bui Quang Minh <[email protected]>

commit e90cfa813da7a527785033a0b247594c2de93dd8 upstream.

This error path

	err_add_pdata:
		for (i = 0; i < mod_data.num; i++)
			kfree(dum[i]);

can be triggered when not all dum's elements are initialized.

Fix this by initializing all dum's elements to NULL.

---
 drivers/usb/gadget/udc/dummy_hcd.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

@@ -2734,7 +2734,7 @@ static int __init init(void)
 {
 	int	retval = -ENOMEM;
 	int	i;
-	struct	dummy *dum[MAX_NUM_UDC];
+	struct	dummy *dum[MAX_NUM_UDC] = {};
 
 	if (usb_disabled())
 		return -ENODEV;

From: Oliver Neukum <[email protected]>

commit 08a02f954b0def3ada8ed6d4b2c7bcb67e885e9c upstream.

I got reports that some models of this old scanner need this when using runtime PM.

---
 drivers/usb/core/quirks.c |    3 +++
 1 file changed, 3 insertions(+)

@@ -342,6 +342,9 @@ static const struct usb_device_id usb_qu
 	{ USB_DEVICE(0x06a3, 0x0006), .driver_info =
 			USB_QUIRK_CONFIG_INTF_STRINGS },
 
+	/* Agfa SNAPSCAN 1212U */
+	{ USB_DEVICE(0x06bd, 0x0001), .driver_info = USB_QUIRK_RESET_RESUME },
+
 	/* Guillemot Webcam Hercules Dualpix Exchange (2nd ID) */
 	{ USB_DEVICE(0x06f8, 0x0804), .driver_info = USB_QUIRK_RESET_RESUME },
 

From: Takashi Iwai <[email protected]>

commit 43d5ca88dfcd35e43010fdd818e067aa9a55f5ba upstream.

syzbot spotted a potential out-of-bounds shift in the USB-audio format parser that receives the arbitrary shift value from the USB descriptor.

Add a range check for avoiding the undefined behavior.

---
 sound/usb/format.c |    2 ++
 1 file changed, 2 insertions(+)

@@ -40,6 +40,8 @@ static u64 parse_audio_format_i_type(str
 	case UAC_VERSION_1:
 	default: {
 		struct uac_format_type_i_discrete_descriptor *fmt = _fmt;
+		if (format >= 64)
+			return 0; /* invalid format */
 		sample_width = fmt->bBitResolution;
 		sample_bytes = fmt->bSubframeSize;
 		format = 1ULL << format;

From: Takashi Iwai <[email protected]>

commit c6dde8ffd071aea9d1ce64279178e470977b235c upstream.

The current channel-map control implementation in USB-audio driver may lead to an error message like
"control 3:0:0:Playback Channel Map:0: access overflow"
when CONFIG_SND_CTL_VALIDATION is set. It's because the chmap get callback clears the whole array no matter which count is set, and rather the false-positive detection.

This patch fixes the problem by clearing only the needed array range at usb_chmap_ctl_get().

---
 sound/usb/stream.c |    6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

@@ -193,16 +193,16 @@ static int usb_chmap_ctl_get(struct snd_
 	struct snd_pcm_chmap *info = snd_kcontrol_chip(kcontrol);
 	struct snd_usb_substream *subs = info->private_data;
 	struct snd_pcm_chmap_elem *chmap = NULL;
-	int i;
+	int i = 0;
 
-	memset(ucontrol->value.integer.value, 0,
-	       sizeof(ucontrol->value.integer.value));
 	if (subs->cur_audiofmt)
 		chmap = subs->cur_audiofmt->chmap;
 	if (chmap) {
 		for (i = 0; i < chmap->channels; i++)
 			ucontrol->value.integer.value[i] = chmap->map[i];
 	}
+	for (; i < subs->channels_max; i++)
+		ucontrol->value.integer.value[i] = 0;
 	return 0;
 }
 

From: Li Jun <[email protected]>

commit c1373f10479b624fb6dba0805d673e860f1b421d upstream.

If a USB2 device wakeup is not enabled/supported the link state may still be in U0 in xhci_bus_suspend(), where it's then manually put to suspended U3 state.

Just as with selective suspend the device needs time to enter U3 suspend before continuing with further suspend operations (e.g. system suspend), otherwise we may enter system suspend with link state in U0.

[commit message rewording -Mathias]

---
 drivers/usb/host/xhci-hub.c |    4 ++++
 1 file changed, 4 insertions(+)

@@ -1712,6 +1712,10 @@ retry:
 	hcd->state = HC_STATE_SUSPENDED;
 	bus_state->next_statechange = jiffies + msecs_to_jiffies(10);
 	spin_unlock_irqrestore(&xhci->lock, flags);
+
+	if (bus_state->bus_suspended)
+		usleep_range(5000, 10000);
+
 	return 0;
 }
 

From: Tejas Joglekar <[email protected]>

commit bac1ec551434697ca3c5bb5d258811ba5446866a upstream.

This commit uses the private data passed by parent device to set the quirk for Synopsys xHC. This patch fixes the SNPS xHC hang issue when the data is scattered across small buffers which does not make atleast MPS size for given TRB cache size of SNPS xHC.

---
 drivers/usb/host/xhci-plat.c |    3 +++
 drivers/usb/host/xhci.h      |    1 +
 2 files changed, 4 insertions(+)

@@ -333,6 +333,9 @@ static int xhci_plat_probe(struct platfo
 	if (priv && (priv->quirks & XHCI_SKIP_PHY_INIT))
 		hcd->skip_phy_initialization = 1;
 
+	if (priv && (priv->quirks & XHCI_SG_TRB_CACHE_SIZE_QUIRK))
+		xhci->quirks |= XHCI_SG_TRB_CACHE_SIZE_QUIRK;
+
 	ret = usb_add_hcd(hcd, irq, IRQF_SHARED);
 	if (ret)
 		goto disable_usb_phy;

@@ -1878,6 +1878,7 @@ struct xhci_hcd {
 #define XHCI_RENESAS_FW_QUIRK	BIT_ULL(36)
 #define XHCI_SKIP_PHY_INIT	BIT_ULL(37)
 #define XHCI_DISABLE_SPARSE	BIT_ULL(38)
+#define XHCI_SG_TRB_CACHE_SIZE_QUIRK	BIT_ULL(39)
 
 	unsigned int		num_active_eps;
 	unsigned int		limit_active_eps;

From: Hans de Goede <[email protected]>

commit c4d1ca05b8e68a4b5a3c4455cb6ec25b3df6d9dd upstream.

The xHCI controller on Alpine Ridge LP keeps the whole Thunderbolt controller awake if the host controller is not allowed to sleep. This is the case even if no USB devices are connected to the host.

Add the Intel Alpine Ridge LP product-id to the list of product-ids for which we allow runtime PM by default.

---
 drivers/usb/host/xhci-pci.c |    2 ++
 1 file changed, 2 insertions(+)

@@ -47,6 +47,7 @@
 #define PCI_DEVICE_ID_INTEL_DNV_XHCI			0x19d0
 #define PCI_DEVICE_ID_INTEL_ALPINE_RIDGE_2C_XHCI	0x15b5
 #define PCI_DEVICE_ID_INTEL_ALPINE_RIDGE_4C_XHCI	0x15b6
+#define PCI_DEVICE_ID_INTEL_ALPINE_RIDGE_LP_XHCI	0x15c1
 #define PCI_DEVICE_ID_INTEL_ALPINE_RIDGE_C_2C_XHCI	0x15db
 #define PCI_DEVICE_ID_INTEL_ALPINE_RIDGE_C_4C_XHCI	0x15d4
 #define PCI_DEVICE_ID_INTEL_TITAN_RIDGE_2C_XHCI		0x15e9

@@ -232,6 +233,7 @@ static void xhci_pci_quirks(struct devic
 	if (pdev->vendor == PCI_VENDOR_ID_INTEL &&
 	    (pdev->device == PCI_DEVICE_ID_INTEL_ALPINE_RIDGE_2C_XHCI ||
 	     pdev->device == PCI_DEVICE_ID_INTEL_ALPINE_RIDGE_4C_XHCI ||
+	     pdev->device == PCI_DEVICE_ID_INTEL_ALPINE_RIDGE_LP_XHCI ||
 	     pdev->device == PCI_DEVICE_ID_INTEL_ALPINE_RIDGE_C_2C_XHCI ||
 	     pdev->device == PCI_DEVICE_ID_INTEL_ALPINE_RIDGE_C_4C_XHCI ||
 	     pdev->device == PCI_DEVICE_ID_INTEL_TITAN_RIDGE_2C_XHCI ||

From: Mika Westerberg <[email protected]>

commit 5a8e3229ac27956bdcc25b2709e5d196d109a27a upstream.

Intel Maple Ridge is successor of Titan Ridge Thunderbolt controller. As Titan Ridge this one also includes xHCI host controller. In order to safe energy we should put it to low power state by default when idle. For this reason allow host runtime PM for Maple Ridge.

---
 drivers/usb/host/xhci-pci.c |    4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

@@ -56,6 +56,7 @@
 #define PCI_DEVICE_ID_INTEL_ICE_LAKE_XHCI		0x8a13
 #define PCI_DEVICE_ID_INTEL_CML_XHCI			0xa3af
 #define PCI_DEVICE_ID_INTEL_TIGER_LAKE_XHCI		0x9a13
+#define PCI_DEVICE_ID_INTEL_MAPLE_RIDGE_XHCI		0x1138
 
 #define PCI_DEVICE_ID_AMD_PROMONTORYA_4			0x43b9
 #define PCI_DEVICE_ID_AMD_PROMONTORYA_3			0x43ba

@@ -240,7 +241,8 @@ static void xhci_pci_quirks(struct devic
 	     pdev->device == PCI_DEVICE_ID_INTEL_TITAN_RIDGE_4C_XHCI ||
 	     pdev->device == PCI_DEVICE_ID_INTEL_TITAN_RIDGE_DD_XHCI ||
 	     pdev->device == PCI_DEVICE_ID_INTEL_ICE_LAKE_XHCI ||
-	     pdev->device == PCI_DEVICE_ID_INTEL_TIGER_LAKE_XHCI))
+	     pdev->device == PCI_DEVICE_ID_INTEL_TIGER_LAKE_XHCI ||
+	     pdev->device == PCI_DEVICE_ID_INTEL_MAPLE_RIDGE_XHCI))
 		xhci->quirks |= XHCI_DEFAULT_PM_RUNTIME_ALLOW;
 
 	if (pdev->vendor == PCI_VENDOR_ID_ETRON &&

From: Oliver Neukum <[email protected]>

commit 8010622c86ca5bb44bc98492f5968726fc7c7a21 upstream.

UAS does not share the pessimistic assumption storage is making that devices cannot deal with WRITE_SAME. A few devices supported by UAS, are reported to not deal well with WRITE_SAME. Those need a quirk.

Add it to the device that needs it.

---
 Documentation/admin-guide/kernel-parameters.txt |    1 +
 drivers/usb/storage/uas.c                       |    3 +++
 drivers/usb/storage/unusual_uas.h               |    7 +++++--
 drivers/usb/storage/usb.c                       |    3 +++
 include/linux/usb_usual.h                       |    2 ++
 5 files changed, 14 insertions(+), 2 deletions(-)

@@ -5663,6 +5663,7 @@
 					device);
 				j = NO_REPORT_LUNS (don't use report luns
 					command, uas only);
+				k = NO_SAME (do not use WRITE_SAME, uas only)
 				l = NOT_LOCKABLE (don't try to lock and
 					unlock ejectable media, not on uas);
 				m = MAX_SECTORS_64 (don't transfer more

@@ -867,6 +867,9 @@ static int uas_slave_configure(struct sc
 	if (devinfo->flags & US_FL_NO_READ_CAPACITY_16)
 		sdev->no_read_capacity_16 = 1;
 
+	/* Some disks cannot handle WRITE_SAME */
+	if (devinfo->flags & US_FL_NO_SAME)
+		sdev->no_write_same = 1;
 	/*
 	 * Some disks return the total number of blocks in response
 	 * to READ CAPACITY rather than the highest block number.

@@ -35,12 +35,15 @@ UNUSUAL_DEV(0x054c, 0x087d, 0x0000, 0x99
 		USB_SC_DEVICE, USB_PR_DEVICE, NULL,
 		US_FL_NO_REPORT_OPCODES),
 
-/* Reported-by: Julian Groß <[email protected]> */
+/*
+ *  Initially Reported-by: Julian Groß <[email protected]>
+ *  Further reports David C. Partridge <[email protected]>
+ */
 UNUSUAL_DEV(0x059f, 0x105f, 0x0000, 0x9999,
 		"LaCie",
 		"2Big Quadra USB3",
 		USB_SC_DEVICE, USB_PR_DEVICE, NULL,
-		US_FL_NO_REPORT_OPCODES),
+		US_FL_NO_REPORT_OPCODES | US_FL_NO_SAME),
 
 /*
  * Apricorn USB3 dongle sometimes returns "USBSUSBSUSBS" in response to SCSI

@@ -541,6 +541,9 @@ void usb_stor_adjust_quirks(struct usb_d
 		case 'j':
 			f |= US_FL_NO_REPORT_LUNS;
 			break;
+		case 'k':
+			f |= US_FL_NO_SAME;
+			break;
 		case 'l':
 			f |= US_FL_NOT_LOCKABLE;
 			break;

@@ -84,6 +84,8 @@
 		/* Cannot handle REPORT_LUNS */			\
 	US_FLAG(ALWAYS_SYNC, 0x20000000)			\
 		/* lies about caching, so always sync */	\
+	US_FLAG(NO_SAME, 0x40000000)				\
+		/* Cannot handle WRITE_SAME */			\
 
 #define US_FLAG(name, value)	US_FL_##name = value ,
 enum { US_DO_ALL_FLAGS };

From: Thomas Gleixner <[email protected]>

commit 862ee699fefe1e6d6f2c1518395f0b999b8beb15 upstream.

The console part of sisusbvga is broken vs. printk(). It uses in_atomic() to detect contexts in which it cannot sleep despite the big fat comment in preempt.h which says: Do not use in_atomic() in driver code.

in_atomic() does not work on kernels with CONFIG_PREEMPT_COUNT=n which means that spin/rw_lock held regions are not detected by it.

There is no way to make this work by handing context information through to the driver and this only can be solved once the core printk infrastructure supports sleepable console drivers.

Make it depend on BROKEN for now.

---
 drivers/usb/misc/sisusbvga/Kconfig |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

@@ -16,7 +16,7 @@ config USB_SISUSBVGA
 
 config USB_SISUSBVGA_CON
 	bool "Text console and mode switching support" if USB_SISUSBVGA
-	depends on VT
+	depends on VT && BROKEN
 	select FONT_8x16
 	help
 	  Say Y here if you want a VGA text console via the USB dongle or

From: Takashi Iwai <[email protected]>

commit 175b8d89fe292796811fdee87fa39799a5b6b87a upstream.

syzbot spotted a potential out-of-bounds shift in the PCM OSS layer where it calculates the buffer size with the arbitrary shift value given via an ioctl.

Add a range check for avoiding the undefined behavior.
As the value can be treated by a signed integer, the max shift should be 30.

---
 sound/core/oss/pcm_oss.c |    6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

@@ -1935,11 +1935,15 @@ static int snd_pcm_oss_set_subdivide(str
 static int snd_pcm_oss_set_fragment1(struct snd_pcm_substream *substream, unsigned int val)
 {
 	struct snd_pcm_runtime *runtime;
+	int fragshift;
 
 	runtime = substream->runtime;
 	if (runtime->oss.subdivision || runtime->oss.fragshift)
 		return -EINVAL;
-	runtime->oss.fragshift = val & 0xffff;
+	fragshift = val & 0xffff;
+	if (fragshift >= 31)
+		return -EINVAL;
+	runtime->oss.fragshift = fragshift;
 	runtime->oss.maxfrags = (val >> 16) & 0xffff;
 	if (runtime->oss.fragshift < 4)		/* < 16 */
 		runtime->oss.fragshift = 4;

From: Alexander Sverdlin <[email protected]>

commit d96f04d347e4011977abdbb4da5d8f303ebd26f8 upstream.

It has been observed that once per 300-1300 port openings the first transmitted byte is being corrupted on AM3352 ("v" written to FIFO appeared as "e" on the wire). It only happened if single byte has been transmitted right after port open, which means, DMA is not used for this transfer and the corruption never happened afterwards.

Therefore I've carefully re-read the MDR1 errata (link below), which says "when accessing the MDR1 registers that causes a dummy under-run condition that will freeze the UART in IrDA transmission. In UART mode, this may corrupt the transferred data". Strictly speaking, omap_8250_mdr1_errataset() performs a read access and if the value is the same as should be written, exits without errata-recommended FIFO reset.

A brief check of the serial_omap_mdr1_errataset() from the competing omap-serial driver showed it has no read access of MDR1. After removing the read access from omap_8250_mdr1_errataset() the data corruption never happened any more.

---
 drivers/tty/serial/8250/8250_omap.c |    5 -----
 1 file changed, 5 deletions(-)

@@ -184,11 +184,6 @@ static void omap_8250_mdr1_errataset(str
 				     struct omap8250_priv *priv)
 {
 	u8 timeout = 255;
-	u8 old_mdr1;
-
-	old_mdr1 = serial_in(up, UART_OMAP_MDR1);
-	if (old_mdr1 == priv->mdr1)
-		return;
 
 	serial_out(up, UART_OMAP_MDR1, priv->mdr1);
 	udelay(2);

hello,

Compiled and booted 5.10.2-rc1+. No typical dmesg regression or regressions

software engineer
rajagiri school of engineering and technology - autonomous

Build results:

	total: 154 pass: 154 fail: 0
Qemu test results:
	total: 427 pass: 427 fail: 0

Guenter

Thanks for testing these and letting me know.

greg k-h

Results from Linaro’s test farm.
No regressions on arm64, arm, x86_64, and i386.

Summary
------------------------------------------------------------------------

kernel: 5.10.2-rc1
git repo: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable-rc.git
git branch: linux-5.10.y
git commit: c96cfd687a3f1d1d461dd4a73eb51410c4fd45d8
git describe: v5.10.1-17-gc96cfd687a3f
Test details: https://qa-reports.linaro.org/lkft/linux-stable-rc-linux-5.10.y/build/v5.10.1-17-gc96cfd687a3f

No regressions (compared to build v5.10.1)

No fixes (compared to build v5.10.1)

Ran 51496 total tests in the following environments and test suites.

Environments
--------------
- arc
- arm
- arm64
- dragonboard-410c
- hi6220-hikey
- i386
- juno-r2
- juno-r2-compat
- juno-r2-kasan
- mips
- parisc
- powerpc
- qemu-arm-clang
- qemu-arm64-clang
- qemu-arm64-kasan
- qemu-i386-clang
- qemu-x86_64-clang
- qemu-x86_64-kasan
- qemu-x86_64-kcsan
- qemu_arm
- qemu_arm64
- qemu_arm64-compat
- qemu_i386
- qemu_x86_64
- qemu_x86_64-compat
- riscv
- s390
- sh
- sparc
- x15
- x86
- x86-kasan

Test Suites
-----------
* build
* fwts
* install-android-platform-tools-r2600
* kselftest
* kselftest-vsyscall-mode-native
* kselftest-vsyscall-mode-none
* kunit
* kvm-unit-tests
* libhugetlbfs
* linux-log-parser
* ltp-cap_bounds-tests
* ltp-commands-tests
* ltp-containers-tests
* ltp-controllers-tests
* ltp-cpuhotplug-tests
* ltp-crypto-tests
* ltp-cve-tests
* ltp-dio-tests
* ltp-fcntl-locktests-tests
* ltp-filecaps-tests
* ltp-fs_bind-tests
* ltp-fs_perms_simple-tests
* ltp-fs-tests
* ltp-fsx-tests
* ltp-hugetlb-tests
* ltp-io-tests
* ltp-ipc-tests
* ltp-math-tests
* ltp-mm-tests
* ltp-nptl-tests
* ltp-open-posix-tests
* ltp-pty-tests
* ltp-sched-tests
* ltp-securebits-tests
* ltp-syscalls-tests
* ltp-tracing-tests
* network-basic-tests
* perf
* rcutorture
* v4l2-compliance

Linaro LKFT
https://lkft.linaro.org

Thanks for testing these and letting me know.

greg k-h

Test results for stable-v5.10:

    12 builds:	12 pass, 0 fail
    26 boots:	26 pass, 0 fail
    64 tests:	63 pass, 1 fail

Linux version: 5.10.2-rc1-gc96cfd687a3f
Boards tested: tegra124-jetson-tk1, tegra186-p2771-0000,

                tegra194-p2972-0000, tegra20-ventana,
                tegra210-p2371-2180, tegra210-p3450-0000,
                tegra30-cardhu-a04

Test failures: tegra194-p2972-0000: boot.py

Same warning failure as before. The fix for this is now in the mainline if you would like to pick it up ...

commit c9f64d1fc101c64ea2be1b2e562b4395127befc9

Author: Thierry Reding <[email protected]>
Date:   Tue Nov 10 08:37:57 2020 +0100

net: ipconfig: Avoid spurious blank lines in boot log

Otherwise ...

Cheers
Jon

nvpublic

I've now queued this up for the next release, thanks for testing these and letting me know.

greg k-h