iv/linux
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

x86/vsyscall/64: Use proper accessor to update P4D entry

Browse Source 
commit 31ad7f8e7dc94d3b85ccf9b6141ce6dfd35a1781 upstream.

Writing to it directly does not work for Xen PV guests.

Fixes: 49275fef986a ("x86/vsyscall/64: Explicitly set _PAGE_USER in the pagetable hierarchy")
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Juergen Gross <jgross@suse.com>
Acked-by: Andy Lutomirski <luto@kernel.org>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20180319143154.3742-1-boris.ostrovsky@oracle.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Boris Ostrovsky 2018-03-19 10:31:54 -04:00 committed by Greg Kroah-Hartman
parent 852d9679a7
commit 373ccbd6eb
1 changed files with 1 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
arch/x86/entry/vsyscall/vsyscall_64.c
View File

@ -355,7 +355,7 @@ void __init set_vsyscall_pgtable_user_bits(pgd_t *root)
set_pgd(pgd, __pgd(pgd_val(*pgd) | _PAGE_USER));
p4d = p4d_offset(pgd, VSYSCALL_ADDR);
#if CONFIG_PGTABLE_LEVELS >= 5
p4d->p4d |= _PAGE_USER;
set_p4d(p4d, __p4d(p4d_val(*p4d) | _PAGE_USER));
#endif
pud = pud_offset(p4d, VSYSCALL_ADDR);
set_pud(pud, __pud(pud_val(*pud) | _PAGE_USER));