diff options
| author | Kirill A. Shutemov <[email protected]> | 2018-01-29 14:08:45 +0300 |
|---|---|---|
| committer | Ingo Molnar <[email protected]> | 2018-01-31 08:39:40 +0100 |
| commit | 5bf30316991d5bcda046343ee77d823cf16fdd03 (patch) | |
| tree | 8f5f7413461e1a77bf6407fc6a3aa3fdee58c374 /net/unix/sysctl_net_unix.c | |
| parent | 72906f38934a49faf4d2d38ea9ae32adcf7d5d0c (diff) | |
x86/kexec: Make kexec (mostly) work in 5-level paging mode
Currently kexec() will crash when switching into a 5-level paging
enabled kernel.
I missed that we need to change relocate_kernel() to set CR4.LA57
flag if the kernel has 5-level paging enabled.
I avoided using #ifdef CONFIG_X86_5LEVEL here and inferred if we need to
enable 5-level paging from previous CR4 value. This way the code is
ready for boot-time switching between paging modes.
With this patch applied, in addition to kexec 4-to-4 which always worked,
we can kexec 4-to-5 and 5-to-5 - while 5-to-4 will need more work.
Reported-by: Baoquan He <[email protected]>
Signed-off-by: Kirill A. Shutemov <[email protected]>
Tested-by: Baoquan He <[email protected]>
Cc: <[email protected]> # v4.14+
Cc: Borislav Petkov <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: [email protected]
Fixes: 77ef56e4f0fb ("x86: Enable 5-level paging support via CONFIG_X86_5LEVEL=y")
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>
Diffstat (limited to 'net/unix/sysctl_net_unix.c')
0 files changed, 0 insertions, 0 deletions