# git rev-parse -q --verify 9933819099c4600b41a042f27a074470a43cf6b9^{commit}
9933819099c4600b41a042f27a074470a43cf6b9
already have revision, skipping fetch
# git checkout -q -f -B kisskb 9933819099c4600b41a042f27a074470a43cf6b9
# git clean -qxdf
# < git log -1
# commit 9933819099c4600b41a042f27a074470a43cf6b9
# Author: Christophe Leroy <christophe.leroy@c-s.fr>
# Date:   Mon Jan 27 10:42:04 2020 +0000
# 
#     powerpc/32s: Fix CPU wake-up from sleep mode
#     
#     Commit f7354ccac844 ("powerpc/32: Remove CURRENT_THREAD_INFO and
#     rename TI_CPU") broke the CPU wake-up from sleep mode (i.e. when
#     _TLF_SLEEPING is set) by delaying the tovirt(r2, r2).
#     
#     This is because r2 is not restored by fast_exception_return. It used
#     to work (by chance ?) because CPU wake-up interrupt never comes from
#     user, so r2 is expected to point to 'current' on return.
#     
#     Commit e2fb9f544431 ("powerpc/32: Prepare for Kernel Userspace Access
#     Protection") broke it even more by clobbering r0 which is not
#     restored by fast_exception_return either.
#     
#     Use r6 instead of r0. This is possible because r3-r6 are restored by
#     fast_exception_return and only r3-r5 are used for exception arguments.
#     
#     For r2 it could be converted back to virtual address, but stay on the
#     safe side and restore it from the stack instead. It should be live
#     in the cache at that moment, so loading from the stack should make
#     no difference compared to converting it from phys to virt.
#     
#     Fixes: f7354ccac844 ("powerpc/32: Remove CURRENT_THREAD_INFO and rename TI_CPU")
#     Fixes: e2fb9f544431 ("powerpc/32: Prepare for Kernel Userspace Access Protection")
#     Cc: stable@vger.kernel.org
#     Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
#     Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
#     Link: https://lore.kernel.org/r/6d02c3ae6ad77af34392e98117e44c2bf6d13ba1.1580121710.git.christophe.leroy@c-s.fr
# < /opt/cross/kisskb/gcc-4.6.3-nolibc/sh4-linux/bin/sh4-linux-gcc --version
# < /opt/cross/kisskb/gcc-4.6.3-nolibc/sh4-linux/bin/sh4-linux-ld --version
# < git log --format=%s --max-count=1 9933819099c4600b41a042f27a074470a43cf6b9
# < make -s -j 80 ARCH=sh O=/kisskb/build/powerpc-next_sh-defconfig_sh4 CROSS_COMPILE=/opt/cross/kisskb/gcc-4.6.3-nolibc/sh4-linux/bin/sh4-linux-  defconfig
# make -s -j 80 ARCH=sh O=/kisskb/build/powerpc-next_sh-defconfig_sh4 CROSS_COMPILE=/opt/cross/kisskb/gcc-4.6.3-nolibc/sh4-linux/bin/sh4-linux-  
  Generating include/generated/machtypes.h
<stdin>:1511:2: warning: #warning syscall clone3 not implemented [-Wcpp]
/kisskb/src/arch/sh/kernel/cpu/sh4/../sh3/../../entry-common.S: Assembler messages:
/kisskb/src/arch/sh/kernel/cpu/sh4/../sh3/../../entry-common.S:385: Warning: overflow in branch to syscall_exit_work; converted into longer instruction sequence
/kisskb/src/arch/sh/kernel/cpu/sh4/../sh3/../../entry-common.S:388: Warning: overflow in branch to syscall_exit_work; converted into longer instruction sequence
/kisskb/src/kernel/printk/printk.c: In function 'devkmsg_sysctl_set_loglvl':
/kisskb/src/kernel/printk/printk.c:204:16: warning: 'old' may be used uninitialized in this function [-Wuninitialized]
/kisskb/src/mm/vmstat.c: In function 'sysctl_vm_numa_stat_handler':
/kisskb/src/mm/vmstat.c:90:5: warning: 'oldval' may be used uninitialized in this function [-Wuninitialized]
/kisskb/src/fs/proc/inode.c: In function 'proc_reg_open':
/kisskb/src/include/linux/list.h:65:12: warning: 'pdeo' may be used uninitialized in this function [-Wuninitialized]
/kisskb/src/fs/proc/inode.c:338:21: note: 'pdeo' was declared here
/kisskb/src/fs/ext4/extents.c: In function 'ext4_convert_unwritten_io_end_vec':
/kisskb/src/fs/ext4/extents.c:5054:23: warning: 'ret' may be used uninitialized in this function [-Wuninitialized]
/kisskb/src/fs/ext4/readpage.c: In function 'ext4_mpage_readpages':
/kisskb/src/fs/ext4/readpage.c:412:1: warning: the frame size of 1180 bytes is larger than 1024 bytes [-Wframe-larger-than=]
/kisskb/src/drivers/base/regmap/regmap.c: In function 'regmap_raw_read':
/kisskb/src/drivers/base/regmap/regmap.c:2591:6: warning: 'ret' may be used uninitialized in this function [-Wuninitialized]
/kisskb/src/drivers/base/regmap/regmap.c: In function '_regmap_raw_write':
/kisskb/src/drivers/base/regmap/regmap.c:1852:6: warning: 'ret' may be used uninitialized in this function [-Wuninitialized]
/kisskb/src/drivers/sh/clk/cpg.c: In function 'r8':
/kisskb/src/drivers/sh/clk/cpg.c:41:2: warning: passing argument 1 of 'ioread8' discards 'const' qualifier from pointer target type [enabled by default]
/kisskb/src/include/asm-generic/iomap.h:29:21: note: expected 'void *' but argument is of type 'const void *'
/kisskb/src/drivers/sh/clk/cpg.c: In function 'r16':
/kisskb/src/drivers/sh/clk/cpg.c:46:2: warning: passing argument 1 of 'ioread16' discards 'const' qualifier from pointer target type [enabled by default]
/kisskb/src/include/asm-generic/iomap.h:30:21: note: expected 'void *' but argument is of type 'const void *'
/kisskb/src/drivers/sh/clk/cpg.c: In function 'r32':
/kisskb/src/drivers/sh/clk/cpg.c:51:2: warning: passing argument 1 of 'ioread32' discards 'const' qualifier from pointer target type [enabled by default]
/kisskb/src/include/asm-generic/iomap.h:32:21: note: expected 'void *' but argument is of type 'const void *'
/kisskb/src/mm/hugetlb.c: In function 'alloc_pool_huge_page':
/kisskb/src/mm/hugetlb.c:1426:5: warning: 'page' may be used uninitialized in this function [-Wuninitialized]
/kisskb/src/fs/mpage.c: In function '__mpage_writepage':
/kisskb/src/fs/mpage.c:690:1: warning: the frame size of 1148 bytes is larger than 1024 bytes [-Wframe-larger-than=]
/kisskb/src/fs/mpage.c: In function 'do_mpage_readpage':
/kisskb/src/fs/mpage.c:338:1: warning: the frame size of 1108 bytes is larger than 1024 bytes [-Wframe-larger-than=]
/kisskb/src/drivers/usb/core/devio.c: In function 'async_completed':
/kisskb/src/drivers/usb/core/devio.c:625:23: warning: 'errno' may be used uninitialized in this function [-Wuninitialized]
  Kernel: arch/sh/boot/zImage is ready
Completed OK
# rm -rf /kisskb/build/powerpc-next_sh-defconfig_sh4
# Build took: 0:00:44.041884