# git rev-parse -q --verify 8b11ec1b5ffb54f71cb5a5e5c8c4d36e5d113085^{commit}
8b11ec1b5ffb54f71cb5a5e5c8c4d36e5d113085
already have revision, skipping fetch
# git checkout -q -f -B kisskb 8b11ec1b5ffb54f71cb5a5e5c8c4d36e5d113085
# git clean -qxdf
# < git log -1
# commit 8b11ec1b5ffb54f71cb5a5e5c8c4d36e5d113085
# Author: Linus Torvalds <torvalds@linux-foundation.org>
# Date:   Wed Aug 1 13:43:38 2018 -0700
# 
#     mm: do not initialize TLB stack vma's with vma_init()
#     
#     Commit 2c4541e24c55 ("mm: use vma_init() to initialize VMAs on stack and
#     data segments") tried to initialize various left-over ad-hoc vma's
#     "properly", but actually made things worse for the temporary vma's used
#     for TLB flushing.
#     
#     vma_init() doesn't actually initialize all of the vma, just a few
#     fields, so doing something like
#     
#        -       struct vm_area_struct vma = { .vm_mm = tlb->mm, };
#        +       struct vm_area_struct vma;
#        +
#        +       vma_init(&vma, tlb->mm);
#     
#     was actually very bad: instead of having a nicely initialized vma with
#     every field but "vm_mm" zeroed, you'd have an entirely uninitialized vma
#     with only a couple of fields initialized.  And they weren't even fields
#     that the code in question mostly cared about.
#     
#     The flush_tlb_range() function takes a "struct vma" rather than a
#     "struct mm_struct", because a few architectures actually care about what
#     kind of range it is - being able to only do an ITLB flush if it's a
#     range that doesn't have data accesses enabled, for example.  And all the
#     normal users already have the vma for doing the range invalidation.
#     
#     But a few people want to call flush_tlb_range() with a range they just
#     made up, so they also end up using a made-up vma.  x86 just has a
#     special "flush_tlb_mm_range()" function for this, but other
#     architectures (arm and ia64) do the "use fake vma" thing instead, and
#     thus got caught up in the vma_init() changes.
#     
#     At the same time, the TLB flushing code really doesn't care about most
#     other fields in the vma, so vma_init() is just unnecessary and
#     pointless.
#     
#     This fixes things by having an explicit "this is just an initializer for
#     the TLB flush" initializer macro, which is used by the arm/arm64/ia64
#     people who mis-use this interface with just a dummy vma.
#     
#     Fixes: 2c4541e24c55 ("mm: use vma_init() to initialize VMAs on stack and data segments")
#     Cc: Dmitry Vyukov <dvyukov@google.com>
#     Cc: Oleg Nesterov <oleg@redhat.com>
#     Cc: Andrea Arcangeli <aarcange@redhat.com>
#     Cc: Kirill Shutemov <kirill.shutemov@linux.intel.com>
#     Cc: Andrew Morton <akpm@linux-foundation.org>
#     Cc: John Stultz <john.stultz@linaro.org>
#     Cc: Hugh Dickins <hughd@google.com>
#     Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
# < /opt/cross/kisskb/gcc-4.6.3-nolibc/mips-linux/bin/mips-linux-gcc --version
# < git log --format=%s --max-count=1 8b11ec1b5ffb54f71cb5a5e5c8c4d36e5d113085
# < make -s -j 48 ARCH=mips O=/kisskb/build/linus_mips-defconfig_mips CROSS_COMPILE=/opt/cross/kisskb/gcc-4.6.3-nolibc/mips-linux/bin/mips-linux-  defconfig
# make -s -j 48 ARCH=mips O=/kisskb/build/linus_mips-defconfig_mips CROSS_COMPILE=/opt/cross/kisskb/gcc-4.6.3-nolibc/mips-linux/bin/mips-linux-  
/kisskb/src/arch/mips/vdso/Makefile:32: MIPS VDSO requires binutils >= 2.25
/kisskb/src/arch/mips/vdso/Makefile:32: MIPS VDSO requires binutils >= 2.25
/kisskb/src/kernel/printk/printk.c: In function 'devkmsg_sysctl_set_loglvl':
/kisskb/src/kernel/printk/printk.c:183:16: warning: 'old' may be used uninitialized in this function [-Wuninitialized]
/kisskb/src/kernel/rcu/srcutree.c: In function 'init_srcu_struct_fields':
/kisskb/src/kernel/rcu/srcutree.c:146:32: warning: 'levelspread[<U61e0>]' may be used uninitialized in this function [-Wuninitialized]
/kisskb/src/kernel/rcu/srcutree.c:94:6: note: 'levelspread[<U61e0>]' was declared here
/kisskb/src/drivers/base/regmap/regmap.c: In function '_regmap_raw_write':
/kisskb/src/drivers/base/regmap/regmap.c:1819:6: warning: 'ret' may be used uninitialized in this function [-Wuninitialized]
/kisskb/src/drivers/base/regmap/regmap.c: In function 'regmap_raw_read':
/kisskb/src/drivers/base/regmap/regmap.c:2497:6: warning: 'ret' may be used uninitialized in this function [-Wuninitialized]
/kisskb/src/kernel/cgroup/cgroup-v1.c: In function 'cgroup1_mount':
/kisskb/src/kernel/cgroup/cgroup-v1.c:1256:20: warning: 'root' 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:339:21: note: 'pdeo' was declared here
/kisskb/src/drivers/tty/serial/8250/8250_core.c: In function 'univ8250_release_irq':
/kisskb/src/drivers/tty/serial/8250/8250_core.c:251:18: warning: 'i' may be used uninitialized in this function [-Wuninitialized]
/kisskb/src/drivers/tty/serial/8250/8250_core.c:231:19: note: 'i' was declared here
/kisskb/src/arch/mips/vdso/Makefile:32: MIPS VDSO requires binutils >= 2.25
/kisskb/src/kernel/printk/printk.c: In function 'devkmsg_sysctl_set_loglvl':
/kisskb/src/kernel/printk/printk.c:183:16: warning: 'old' may be used uninitialized in this function [-Wuninitialized]
FIT description: Linux 4.18.0-rc7-g8b11ec1
Created:         Thu Aug  2 10:00:03 2018
 Image 0 (kernel@0)
  Description:  Linux 4.18.0-rc7-g8b11ec1
  Created:      Thu Aug  2 10:00:03 2018
  Type:         Kernel Image
  Compression:  gzip compressed
  Data Size:    4340065 Bytes = 4238.34 kB = 4.14 MB
  Architecture: MIPS
  OS:           Linux
  Load Address: 0x80100000
  Entry Point:  0x80832210
  Hash algo:    sha1
  Hash value:   c5346436f3af40278612fd918cfac47bbb7765d9
 Image 1 (fdt@boston)
  Description:  img,boston Device Tree
  Created:      Thu Aug  2 10:00:03 2018
  Type:         Flat Device Tree
  Compression:  uncompressed
  Data Size:    3668 Bytes = 3.58 kB = 0.00 MB
  Architecture: MIPS
  Hash algo:    sha1
  Hash value:   569c37cc891ce1e1f3a193cb41cc691a5d2debb5
 Image 2 (fdt@ni169445)
  Description:  NI 169445 device tree
  Created:      Thu Aug  2 10:00:03 2018
  Type:         Flat Device Tree
  Compression:  uncompressed
  Data Size:    1871 Bytes = 1.83 kB = 0.00 MB
  Architecture: MIPS
  Hash algo:    sha1
  Hash value:   51b89b31605ee62038c8468c429af091dfc75ec7
 Image 3 (fdt@xilfpga)
  Description:  MIPSfpga (xilfpga) Device Tree
  Created:      Thu Aug  2 10:00:03 2018
  Type:         Flat Device Tree
  Compression:  uncompressed
  Data Size:    2708 Bytes = 2.64 kB = 0.00 MB
  Architecture: MIPS
  Hash algo:    sha1
  Hash value:   509ce58e44c561d54539e64e9d4b47054e696fc6
 Default Configuration: 'conf@default'
 Configuration 0 (conf@default)
  Description:  Generic Linux kernel
  Kernel:       kernel@0
 Configuration 1 (conf@boston)
  Description:  Boston Linux kernel
  Kernel:       kernel@0
  FDT:          fdt@boston
 Configuration 2 (conf@ni169445)
  Description:  NI 169445 Linux Kernel
  Kernel:       kernel@0
  FDT:          fdt@ni169445
 Configuration 3 (conf@xilfpga)
  Description:  MIPSfpga Linux kernel
  Kernel:       kernel@0
  FDT:          fdt@xilfpga
Completed OK
# rm -rf /kisskb/build/linus_mips-defconfig_mips
# Build took: 0:01:25.601081