# git rev-parse -q --verify a3ac7917b73070010c05b4485b8582a6c9cd69b6^{commit}
a3ac7917b73070010c05b4485b8582a6c9cd69b6
already have revision, skipping fetch
# git checkout -q -f -B kisskb a3ac7917b73070010c05b4485b8582a6c9cd69b6
# git clean -qxdf
# < git log -1
# commit a3ac7917b73070010c05b4485b8582a6c9cd69b6
# Author: Linus Torvalds <torvalds@linux-foundation.org>
# Date:   Mon Mar 25 14:49:00 2019 -0700
# 
#     Revert "parport: daisy: use new parport device model"
#     
#     This reverts commit 1aec4211204d9463d1fd209eb50453de16254599.
#     
#     Steven Rostedt reports that it causes a hang at bootup and bisected it
#     to this commit.
#     
#     The troigger is apparently a module alias for "parport_lowlevel" that
#     points to "parport_pc", which causes a hang with
#     
#         modprobe -q -- parport_lowlevel
#     
#     blocking forever with a backtrace like this:
#     
#         wait_for_completion_killable+0x1c/0x28
#         call_usermodehelper_exec+0xa7/0x108
#         __request_module+0x351/0x3d8
#         get_lowlevel_driver+0x28/0x41 [parport]
#         __parport_register_driver+0x39/0x1f4 [parport]
#         daisy_drv_init+0x31/0x4f [parport]
#         parport_bus_init+0x5d/0x7b [parport]
#         parport_default_proc_register+0x26/0x1000 [parport]
#         do_one_initcall+0xc2/0x1e0
#         do_init_module+0x50/0x1d4
#         load_module+0x1c2e/0x21b3
#         sys_init_module+0xef/0x117
#     
#     Supid says:
#      "Due to the new device model daisy driver will now try to find the
#       parallel ports while trying to register its driver so that it can bind
#       with them. Now, since daisy driver is loaded while parport bus is
#       initialising the list of parport is still empty and it tries to load
#       the lowlevel driver, which has an alias set to parport_pc, now causes
#       a deadlock"
#     
#     But I don't think the daisy driver should be loaded by the parport
#     initialization in the first place, so let's revert the whole change.
#     
#     If the daisy driver can just initialize separately on its own (like a
#     driver should), instead of hooking into the parport init sequence
#     directly, this issue probably would go away.
#     
#     Reported-and-bisected-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
#     Reported-by: Michal Kubecek <mkubecek@suse.cz>
#     Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
#     Cc: Sudip Mukherjee <sudipm.mukherjee@gmail.com>
#     Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
# < /opt/cross/kisskb/br-aarch64-glibc-2016.08-613-ge98b4dd/bin/aarch64-linux-gcc --version
# < /opt/cross/kisskb/br-aarch64-glibc-2016.08-613-ge98b4dd/bin/aarch64-linux-ld --version
# < git log --format=%s --max-count=1 a3ac7917b73070010c05b4485b8582a6c9cd69b6
# < make -s -j 8 ARCH=arm64 O=/kisskb/build/linus_arm64-defconfig_arm64-gcc5.4 CROSS_COMPILE=/opt/cross/kisskb/br-aarch64-glibc-2016.08-613-ge98b4dd/bin/aarch64-linux-  defconfig
# make -s -j 8 ARCH=arm64 O=/kisskb/build/linus_arm64-defconfig_arm64-gcc5.4 CROSS_COMPILE=/opt/cross/kisskb/br-aarch64-glibc-2016.08-613-ge98b4dd/bin/aarch64-linux-  
arch/arm64/Makefile:27: ld does not support --fix-cortex-a53-843419; kernel may be susceptible to erratum
arch/arm64/Makefile:40: LSE atomics not supported by binutils
/kisskb/src/net/sunrpc/xprtsock.c: In function 'xs_read_stream_request.constprop':
/kisskb/src/net/sunrpc/xprtsock.c:529:9: warning: 'ret' may be used uninitialized in this function [-Wmaybe-uninitialized]
  return ret < 0 ? ret : read;
         ^
/kisskb/src/net/sunrpc/xprtsock.c:525:10: warning: 'read' may be used uninitialized in this function [-Wmaybe-uninitialized]
   return read;
          ^
/kisskb/src/drivers/i2c/busses/i2c-sh_mobile.c: In function 'sh_mobile_i2c_isr':
/kisskb/src/drivers/i2c/busses/i2c-sh_mobile.c:399:26: warning: 'data' may be used uninitialized in this function [-Wmaybe-uninitialized]
   pd->msg->buf[real_pos] = data;
                          ^
/kisskb/src/drivers/i2c/busses/i2c-sh_mobile.c:372:16: note: 'data' was declared here
  unsigned char data;
                ^
In file included from /kisskb/src/include/linux/rwsem.h:16:0,
                 from /kisskb/src/include/linux/notifier.h:15,
                 from /kisskb/src/include/linux/clk.h:17,
                 from /kisskb/src/drivers/tty/serial/sh-sci.c:24:
/kisskb/src/drivers/tty/serial/sh-sci.c: In function 'sci_dma_rx_submit':
/kisskb/src/include/linux/spinlock.h:279:3: warning: 'flags' may be used uninitialized in this function [-Wmaybe-uninitialized]
   _raw_spin_unlock_irqrestore(lock, flags); \
   ^
/kisskb/src/drivers/tty/serial/sh-sci.c:1363:16: note: 'flags' was declared here
  unsigned long flags;
                ^
Completed OK
# rm -rf /kisskb/build/linus_arm64-defconfig_arm64-gcc5.4
# Build took: 0:06:09.868515