Refactor RedHat support:

- Isolate file check to different elif (allowing to add more)
- Do the PTI debugfs check first (faster and supposed to be dynamic)
- If pti_enable is 0, don't trust dmesg (supposed to be dynamic)
This commit is contained in:
Vincent Brillault 2018-01-08 12:39:03 +01:00
parent 34ef5ef21b
commit 66f7708095
No known key found for this signature in database
GPG Key ID: CFEA15DE034F0688
1 changed files with 14 additions and 5 deletions

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@ -171,15 +171,20 @@ if [ ! -e /sys/kernel/debug/sched_features ]; then
# try to mount the debugfs hierarchy ourselves and remember it to umount afterwards
mount -t debugfs debugfs /sys/kernel/debug 2>/dev/null && mounted_debugfs=1
fi
if [ -e /sys/kernel/debug/ibrs_enabled -o -e /sys/kernel/debug/x86/ibrs_enabled ]; then
if [ -e /sys/kernel/debug/ibrs_enabled ]; then
# if the file is there, we have IBRS compiled-in
pstatus green YES
ibrs_supported=1
ibrs_enabled=$(cat /sys/kernel/debug/ibrs_enabled 2>/dev/null)
elif [ -e /sys/kernel/debug/x86/ibrs_enabled ]; then
# RedHat uses a different path (see https://access.redhat.com/articles/3311301)
pstatus green YES
ibrs_supported=1
ibrs_enabled=$(cat /sys/kernel/debug/x86/ibrs_enabled 2>/dev/null)
else
pstatus red NO
fi
[ -f /sys/kernel/debug/ibrs_enabled ] && ibrs_enabled=$(cat /sys/kernel/debug/ibrs_enabled 2>/dev/null) || ibrs_enabled=$(cat /sys/kernel/debug/x86/ibrs_enabled 2>/dev/null)
/bin/echo -n "* IBRS enabled for Kernel space: "
# 0 means disabled
# 1 is enabled only for kernel space
@ -285,13 +290,17 @@ if grep ^flags /proc/cpuinfo | grep -qw pti; then
# vanilla PTI patch sets the 'pti' flag in cpuinfo
pstatus green YES
kpti_enabled=1
elif [ -e /sys/kernel/debug/x86/pti_enabled ]; then
# RedHat Backport creates a dedicated file, see https://access.redhat.com/articles/3311301
kpti_enabled=$(cat /sys/kernel/debug/x86/pti_enabled 2>/dev/null)
elif dmesg | grep -Eq 'Kernel/User page tables isolation: enabled|Kernel page table isolation enabled'; then
# if we can't find the flag, grep in dmesg
pstatus green YES
kpti_enabled=1
elif [ -e /sys/kernel/debug/x86/pti_enabled -a "$(cat /sys/kernel/debug/x86/pti_enabled 2>/dev/null)" = 1 ]; then
else
kpti_enabled=0
fi
if [ "$kpti_enabled" = 1 ]; then
pstatus green YES
kpti_enabled=1
else
pstatus red NO
fi