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x86/mm: Do not use paravirtualized calls in native_set_p4d() 

In 4-level paging mode, native_set_p4d() updates the entry in the top-level
page table. With PTI, update to the top-level kernel page table requires
update to the userspace copy of the table as well, using pti_set_user_pgd().

native_set_p4d() uses p4d_val() and pgd_val() to convert types between
p4d_t and pgd_t.

p4d_val() and pgd_val() are paravirtualized and we must not use them in
native helpers, as they crash the boot in paravirtualized environments.

Replace p4d_val() and pgd_val() with native_p4d_val() and
native_pgd_val() in native_set_p4d().

Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: 91f606a8fa ("x86/mm: Replace compile-time checks for 5-level paging with runtime-time checks")
Link: http://lkml.kernel.org/r/20180305081641.4290-1-kirill.shutemov@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This commit is contained in:
Kirill A. Shutemov 2018-03-05 11:16:41 +03:00 committed by Ingo Molnar
parent c100a58360
commit a5b162b2ec
1 changed files with 2 additions and 2 deletions
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4
arch/x86/include/asm/pgtable_64.h
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@ -224,9 +224,9 @@ static inline void native_set_p4d(p4d_t *p4dp, p4d_t p4d)
return;
}
pgd = native_make_pgd(p4d_val(p4d));
pgd = native_make_pgd(native_p4d_val(p4d));
pgd = pti_set_user_pgd((pgd_t *)p4dp, pgd);
*p4dp = native_make_p4d(pgd_val(pgd));
*p4dp = native_make_p4d(native_pgd_val(pgd));
}
static inline void native_p4d_clear(p4d_t *p4d)