Revision 6941051d3028963c3b0b3fcdd0815f2b51b957bb authored by Sudeep Holla on 18 October 2019, 10:58:15 UTC, committed by Rafael J. Wysocki on 22 October 2019, 16:07:30 UTC
Scheduled policy update work may end up racing with the freeing of the policy and unregistering the driver. One possible race is as below, where the cpufreq_driver is unregistered, but the scheduled work gets executed at later stage when, cpufreq_driver is NULL (i.e. after freeing the policy and driver). Unable to handle kernel NULL pointer dereference at virtual address 0000001c pgd = (ptrval) [0000001c] *pgd=80000080204003, *pmd=00000000 Internal error: Oops: 206 [#1] SMP THUMB2 Modules linked in: CPU: 0 PID: 34 Comm: kworker/0:1 Not tainted 5.4.0-rc3-00006-g67f5a8081a4b #86 Hardware name: ARM-Versatile Express Workqueue: events handle_update PC is at cpufreq_set_policy+0x58/0x228 LR is at dev_pm_qos_read_value+0x77/0xac Control: 70c5387d Table: 80203000 DAC: fffffffd Process kworker/0:1 (pid: 34, stack limit = 0x(ptrval)) (cpufreq_set_policy) from (refresh_frequency_limits.part.24+0x37/0x48) (refresh_frequency_limits.part.24) from (handle_update+0x2f/0x38) (handle_update) from (process_one_work+0x16d/0x3cc) (process_one_work) from (worker_thread+0xff/0x414) (worker_thread) from (kthread+0xff/0x100) (kthread) from (ret_from_fork+0x11/0x28) Fixes: 67d874c3b2c6 ("cpufreq: Register notifiers with the PM QoS framework") Signed-off-by: Sudeep Holla <sudeep.holla@arm.com> [ rjw: Cancel the work before dropping the QoS requests ] Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
1 parent 2aac8bd
tags.sh
#!/bin/bash
# SPDX-License-Identifier: GPL-2.0-only
# Generate tags or cscope files
# Usage tags.sh <mode>
#
# mode may be any of: tags, TAGS, cscope
#
# Uses the following environment variables:
# SUBARCH, SRCARCH, srctree
if [ "$KBUILD_VERBOSE" = "1" ]; then
set -x
fi
# RCS_FIND_IGNORE has escaped ()s -- remove them.
ignore="$(echo "$RCS_FIND_IGNORE" | sed 's|\\||g' )"
# tags and cscope files should also ignore MODVERSION *.mod.c files
ignore="$ignore ( -name *.mod.c ) -prune -o"
# Use make KBUILD_ABS_SRCTREE=1 {tags|cscope}
# to force full paths for a non-O= build
if [ "${srctree}" = "." -o -z "${srctree}" ]; then
tree=
else
tree=${srctree}/
fi
# ignore userspace tools
ignore="$ignore ( -path ${tree}tools ) -prune -o"
# Detect if ALLSOURCE_ARCHS is set. If not, we assume SRCARCH
if [ "${ALLSOURCE_ARCHS}" = "" ]; then
ALLSOURCE_ARCHS=${SRCARCH}
elif [ "${ALLSOURCE_ARCHS}" = "all" ]; then
ALLSOURCE_ARCHS=$(find ${tree}arch/ -mindepth 1 -maxdepth 1 -type d -printf '%f ')
fi
# find sources in arch/$1
find_arch_sources()
{
for i in $archincludedir; do
prune="$prune -wholename $i -prune -o"
done
find ${tree}arch/$1 $ignore $prune -name "$2" -not -type l -print;
}
# find sources in arch/$1/include
find_arch_include_sources()
{
include=$(find ${tree}arch/$1/ -name include -type d -print);
if [ -n "$include" ]; then
archincludedir="$archincludedir $include"
find $include $ignore -name "$2" -not -type l -print;
fi
}
# find sources in include/
find_include_sources()
{
find ${tree}include $ignore -name config -prune -o -name "$1" \
-not -type l -print;
}
# find sources in rest of tree
# we could benefit from a list of dirs to search in here
find_other_sources()
{
find ${tree}* $ignore \
\( -path ${tree}include -o -path ${tree}arch -o -name '.tmp_*' \) -prune -o \
-name "$1" -not -type l -print;
}
find_sources()
{
find_arch_sources $1 "$2"
}
all_sources()
{
find_arch_include_sources ${SRCARCH} '*.[chS]'
if [ ! -z "$archinclude" ]; then
find_arch_include_sources $archinclude '*.[chS]'
fi
find_include_sources '*.[chS]'
for arch in $ALLSOURCE_ARCHS
do
find_sources $arch '*.[chS]'
done
find_other_sources '*.[chS]'
}
all_compiled_sources()
{
for i in $(all_sources); do
case "$i" in
*.[cS])
j=${i/\.[cS]/\.o}
j="${j#$tree}"
if [ -e $j ]; then
echo $i
fi
;;
*)
echo $i
;;
esac
done
}
all_target_sources()
{
if [ -n "$COMPILED_SOURCE" ]; then
all_compiled_sources
else
all_sources
fi
}
all_kconfigs()
{
find ${tree}arch/ -maxdepth 1 $ignore \
-name "Kconfig*" -not -type l -print;
for arch in $ALLSOURCE_ARCHS; do
find_sources $arch 'Kconfig*'
done
find_other_sources 'Kconfig*'
}
docscope()
{
(echo \-k; echo \-q; all_target_sources) > cscope.files
cscope -b -f cscope.out
}
dogtags()
{
all_target_sources | gtags -i -f -
}
# Basic regular expressions with an optional /kind-spec/ for ctags and
# the following limitations:
# - No regex modifiers
# - Use \{0,1\} instead of \?, because etags expects an unescaped ?
# - \s is not working with etags, use a space or [ \t]
# - \w works, but does not match underscores in etags
# - etags regular expressions have to match at the start of a line;
# a ^[^#] is prepended by setup_regex unless an anchor is already present
regex_asm=(
'/^\(ENTRY\|_GLOBAL\)(\([[:alnum:]_\\]*\)).*/\2/'
)
regex_c=(
'/^SYSCALL_DEFINE[0-9](\([[:alnum:]_]*\).*/sys_\1/'
'/^BPF_CALL_[0-9](\([[:alnum:]_]*\).*/\1/'
'/^COMPAT_SYSCALL_DEFINE[0-9](\([[:alnum:]_]*\).*/compat_sys_\1/'
'/^TRACE_EVENT(\([[:alnum:]_]*\).*/trace_\1/'
'/^TRACE_EVENT(\([[:alnum:]_]*\).*/trace_\1_rcuidle/'
'/^DEFINE_EVENT([^,)]*, *\([[:alnum:]_]*\).*/trace_\1/'
'/^DEFINE_EVENT([^,)]*, *\([[:alnum:]_]*\).*/trace_\1_rcuidle/'
'/^DEFINE_INSN_CACHE_OPS(\([[:alnum:]_]*\).*/get_\1_slot/'
'/^DEFINE_INSN_CACHE_OPS(\([[:alnum:]_]*\).*/free_\1_slot/'
'/^PAGEFLAG(\([[:alnum:]_]*\).*/Page\1/'
'/^PAGEFLAG(\([[:alnum:]_]*\).*/SetPage\1/'
'/^PAGEFLAG(\([[:alnum:]_]*\).*/ClearPage\1/'
'/^TESTSETFLAG(\([[:alnum:]_]*\).*/TestSetPage\1/'
'/^TESTPAGEFLAG(\([[:alnum:]_]*\).*/Page\1/'
'/^SETPAGEFLAG(\([[:alnum:]_]*\).*/SetPage\1/'
'/\<__SETPAGEFLAG(\([[:alnum:]_]*\).*/__SetPage\1/'
'/\<TESTCLEARFLAG(\([[:alnum:]_]*\).*/TestClearPage\1/'
'/\<__TESTCLEARFLAG(\([[:alnum:]_]*\).*/TestClearPage\1/'
'/\<CLEARPAGEFLAG(\([[:alnum:]_]*\).*/ClearPage\1/'
'/\<__CLEARPAGEFLAG(\([[:alnum:]_]*\).*/__ClearPage\1/'
'/^__PAGEFLAG(\([[:alnum:]_]*\).*/__SetPage\1/'
'/^__PAGEFLAG(\([[:alnum:]_]*\).*/__ClearPage\1/'
'/^PAGEFLAG_FALSE(\([[:alnum:]_]*\).*/Page\1/'
'/\<TESTSCFLAG(\([[:alnum:]_]*\).*/TestSetPage\1/'
'/\<TESTSCFLAG(\([[:alnum:]_]*\).*/TestClearPage\1/'
'/\<SETPAGEFLAG_NOOP(\([[:alnum:]_]*\).*/SetPage\1/'
'/\<CLEARPAGEFLAG_NOOP(\([[:alnum:]_]*\).*/ClearPage\1/'
'/\<__CLEARPAGEFLAG_NOOP(\([[:alnum:]_]*\).*/__ClearPage\1/'
'/\<TESTCLEARFLAG_FALSE(\([[:alnum:]_]*\).*/TestClearPage\1/'
'/^PAGE_TYPE_OPS(\([[:alnum:]_]*\).*/Page\1/'
'/^PAGE_TYPE_OPS(\([[:alnum:]_]*\).*/__SetPage\1/'
'/^PAGE_TYPE_OPS(\([[:alnum:]_]*\).*/__ClearPage\1/'
'/^TASK_PFA_TEST([^,]*, *\([[:alnum:]_]*\))/task_\1/'
'/^TASK_PFA_SET([^,]*, *\([[:alnum:]_]*\))/task_set_\1/'
'/^TASK_PFA_CLEAR([^,]*, *\([[:alnum:]_]*\))/task_clear_\1/'
'/^DEF_MMIO_\(IN\|OUT\)_[XD](\([[:alnum:]_]*\),[^)]*)/\2/'
'/^DEBUGGER_BOILERPLATE(\([[:alnum:]_]*\))/\1/'
'/^DEF_PCI_AC_\(\|NO\)RET(\([[:alnum:]_]*\).*/\2/'
'/^PCI_OP_READ(\(\w*\).*[1-4])/pci_bus_read_config_\1/'
'/^PCI_OP_WRITE(\(\w*\).*[1-4])/pci_bus_write_config_\1/'
'/\<DEFINE_\(RT_MUTEX\|MUTEX\|SEMAPHORE\|SPINLOCK\)(\([[:alnum:]_]*\)/\2/v/'
'/\<DEFINE_\(RAW_SPINLOCK\|RWLOCK\|SEQLOCK\)(\([[:alnum:]_]*\)/\2/v/'
'/\<DECLARE_\(RWSEM\|COMPLETION\)(\([[:alnum:]_]\+\)/\2/v/'
'/\<DECLARE_BITMAP(\([[:alnum:]_]*\)/\1/v/'
'/\(^\|\s\)\(\|L\|H\)LIST_HEAD(\([[:alnum:]_]*\)/\3/v/'
'/\(^\|\s\)RADIX_TREE(\([[:alnum:]_]*\)/\2/v/'
'/\<DEFINE_PER_CPU([^,]*, *\([[:alnum:]_]*\)/\1/v/'
'/\<DEFINE_PER_CPU_SHARED_ALIGNED([^,]*, *\([[:alnum:]_]*\)/\1/v/'
'/\<DECLARE_WAIT_QUEUE_HEAD(\([[:alnum:]_]*\)/\1/v/'
'/\<DECLARE_\(TASKLET\|WORK\|DELAYED_WORK\)(\([[:alnum:]_]*\)/\2/v/'
'/\(^\s\)OFFSET(\([[:alnum:]_]*\)/\2/v/'
'/\(^\s\)DEFINE(\([[:alnum:]_]*\)/\2/v/'
'/\<\(DEFINE\|DECLARE\)_HASHTABLE(\([[:alnum:]_]*\)/\2/v/'
'/\<DEFINE_ID\(R\|A\)(\([[:alnum:]_]\+\)/\2/'
'/\<DEFINE_WD_CLASS(\([[:alnum:]_]\+\)/\1/'
'/\<ATOMIC_NOTIFIER_HEAD(\([[:alnum:]_]\+\)/\1/'
'/\<RAW_NOTIFIER_HEAD(\([[:alnum:]_]\+\)/\1/'
'/\<DECLARE_FAULT_ATTR(\([[:alnum:]_]\+\)/\1/'
'/\<BLOCKING_NOTIFIER_HEAD(\([[:alnum:]_]\+\)/\1/'
'/\<DEVICE_ATTR_\(RW\|RO\|WO\)(\([[:alnum:]_]\+\)/dev_attr_\2/'
'/\<DRIVER_ATTR_\(RW\|RO\|WO\)(\([[:alnum:]_]\+\)/driver_attr_\2/'
'/\<\(DEFINE\|DECLARE\)_STATIC_KEY_\(TRUE\|FALSE\)\(\|_RO\)(\([[:alnum:]_]\+\)/\4/'
)
regex_kconfig=(
'/^[[:blank:]]*\(menu\|\)config[[:blank:]]\+\([[:alnum:]_]\+\)/\2/'
'/^[[:blank:]]*\(menu\|\)config[[:blank:]]\+\([[:alnum:]_]\+\)/CONFIG_\2/'
)
setup_regex()
{
local mode=$1 lang tmp=() r
shift
regex=()
for lang; do
case "$lang" in
asm) tmp=("${regex_asm[@]}") ;;
c) tmp=("${regex_c[@]}") ;;
kconfig) tmp=("${regex_kconfig[@]}") ;;
esac
for r in "${tmp[@]}"; do
if test "$mode" = "exuberant"; then
regex[${#regex[@]}]="--regex-$lang=${r}b"
else
# Remove ctags /kind-spec/
case "$r" in
/*/*/?/)
r=${r%?/}
esac
# Prepend ^[^#] unless already anchored
case "$r" in
/^*) ;;
*)
r="/^[^#]*${r#/}"
esac
regex[${#regex[@]}]="--regex=$r"
fi
done
done
}
exuberant()
{
setup_regex exuberant asm c
all_target_sources | xargs $1 -a \
-I __initdata,__exitdata,__initconst,__ro_after_init \
-I __initdata_memblock \
-I __refdata,__attribute,__maybe_unused,__always_unused \
-I __acquires,__releases,__deprecated,__always_inline \
-I __read_mostly,__aligned,____cacheline_aligned \
-I ____cacheline_aligned_in_smp \
-I __cacheline_aligned,__cacheline_aligned_in_smp \
-I ____cacheline_internodealigned_in_smp \
-I __used,__packed,__packed2__,__must_check,__must_hold \
-I EXPORT_SYMBOL,EXPORT_SYMBOL_GPL,ACPI_EXPORT_SYMBOL \
-I DEFINE_TRACE,EXPORT_TRACEPOINT_SYMBOL,EXPORT_TRACEPOINT_SYMBOL_GPL \
-I static,const \
--extra=+fq --c-kinds=+px --fields=+iaS --langmap=c:+.h \
"${regex[@]}"
setup_regex exuberant kconfig
all_kconfigs | xargs $1 -a \
--langdef=kconfig --language-force=kconfig "${regex[@]}"
}
emacs()
{
setup_regex emacs asm c
all_target_sources | xargs $1 -a "${regex[@]}"
setup_regex emacs kconfig
all_kconfigs | xargs $1 -a "${regex[@]}"
}
xtags()
{
if $1 --version 2>&1 | grep -iq exuberant; then
exuberant $1
elif $1 --version 2>&1 | grep -iq emacs; then
emacs $1
else
all_target_sources | xargs $1 -a
fi
}
# Support um (which uses SUBARCH)
if [ "${ARCH}" = "um" ]; then
if [ "$SUBARCH" = "i386" ]; then
archinclude=x86
elif [ "$SUBARCH" = "x86_64" ]; then
archinclude=x86
else
archinclude=${SUBARCH}
fi
fi
remove_structs=
case "$1" in
"cscope")
docscope
;;
"gtags")
dogtags
;;
"tags")
rm -f tags
xtags ctags
remove_structs=y
;;
"TAGS")
rm -f TAGS
xtags etags
remove_structs=y
;;
esac
# Remove structure forward declarations.
if [ -n "$remove_structs" ]; then
LANG=C sed -i -e '/^\([a-zA-Z_][a-zA-Z0-9_]*\)\t.*\t\/\^struct \1;.*\$\/;"\tx$/d' $1
fi
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