[sparc64] Fix device naming inconsistency between sunhv_console and sunhv_reg (Closes: #926539)

debian/changelog

@@ -1,3 +1,11 @@
+linux (4.19.37-5) UNRELEASED; urgency=medium
+
+  [ Romain Perier ]
+  * [sparc64] Fix device naming inconsistency between sunhv_console and sunhv_reg
+    (Closes: #926539)
+
+ -- Romain Perier <romain.perier@gmail.com>  Wed, 19 Jun 2019 16:20:29 +0200
+
 linux (4.19.37-4) unstable; urgency=high
 
   [ Ben Hutchings ]

debian/patches/bugfix/sparc64/sunhv-fix-device-naming-inconsistency-between-sunhv_console-and-sunhv_reg.patch

@@ -0,0 +1,63 @@
+From foo@baz Wed 19 Jun 2019 02:34:37 PM CEST
+From: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
+Date: Tue, 11 Jun 2019 17:38:37 +0200
+Subject: sunhv: Fix device naming inconsistency between sunhv_console and sunhv_reg
+Bug-Debian: https://bugs.debian.org/926539
+Origin: https://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc.git/commit/?id=07a6d63eb1b54b5fb38092780fe618dfe1d96e23
+
+From: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
+
+[ Upstream commit 07a6d63eb1b54b5fb38092780fe618dfe1d96e23 ]
+
+In d5a2aa24, the name in struct console sunhv_console was changed from "ttyS"
+to "ttyHV" while the name in struct uart_ops sunhv_pops remained unchanged.
+
+This results in the hypervisor console device to be listed as "ttyHV0" under
+/proc/consoles while the device node is still named "ttyS0":
+
+root@osaka:~# cat /proc/consoles
+ttyHV0               -W- (EC p  )    4:64
+tty0                 -WU (E     )    4:1
+root@osaka:~# readlink /sys/dev/char/4:64
+../../devices/root/f02836f0/f0285690/tty/ttyS0
+root@osaka:~#
+
+This means that any userland code which tries to determine the name of the
+device file of the hypervisor console device can not rely on the information
+provided by /proc/consoles. In particular, booting current versions of debian-
+installer inside a SPARC LDOM will fail with the installer unable to determine
+the console device.
+
+After renaming the device in struct uart_ops sunhv_pops to "ttyHV" as well,
+the inconsistency is fixed and it is possible again to determine the name
+of the device file of the hypervisor console device by reading the contents
+of /proc/console:
+
+root@osaka:~# cat /proc/consoles
+ttyHV0               -W- (EC p  )    4:64
+tty0                 -WU (E     )    4:1
+root@osaka:~# readlink /sys/dev/char/4:64
+../../devices/root/f02836f0/f0285690/tty/ttyHV0
+root@osaka:~#
+
+With this change, debian-installer works correctly when installing inside
+a SPARC LDOM.
+
+Signed-off-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
+Signed-off-by: David S. Miller <davem@davemloft.net>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ drivers/tty/serial/sunhv.c |    2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+--- a/drivers/tty/serial/sunhv.c
++++ b/drivers/tty/serial/sunhv.c
+@@ -397,7 +397,7 @@ static const struct uart_ops sunhv_pops
+ static struct uart_driver sunhv_reg = {
+ 	.owner			= THIS_MODULE,
+ 	.driver_name		= "sunhv",
+-	.dev_name		= "ttyS",
++	.dev_name		= "ttyHV",
+ 	.major			= TTY_MAJOR,
+ };
+ 

debian/patches/series

@@ -83,6 +83,7 @@ bugfix/mips/MIPS-Loongson-Introduce-and-use-loongson_llsc_mb.patch
 bugfix/powerpc/powerpc-vdso-make-vdso32-installation-conditional-in.patch
 bugfix/mips/MIPS-scall64-o32-Fix-indirect-syscall-number-load.patch
 bugfix/mips/MIPS-Bounds-check-virt_addr_valid.patch
+bugfix/sparc64/sunhv-fix-device-naming-inconsistency-between-sunhv_console-and-sunhv_reg.patch
 
 # Arch features
 features/mips/MIPS-increase-MAX-PHYSMEM-BITS-on-Loongson-3-only.patch