linux-kernel - [GIT pull] efi updates for 4.17

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Date:   Sun, 15 Apr 2018 19:26:54 +0200 (CEST)
From:   Thomas Gleixner <tglx@...utronix.de>
To:     Linus Torvalds <torvalds@...ux-foundation.org>
cc:     LKML <linux-kernel@...r.kernel.org>, Ingo Molnar <mingo@...nel.org>
Subject: [GIT pull] efi updates for 4.17

Linus,

please pull the latest efi-urgent-for-linus git tree from:

   git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git efi-urgent-for-linus

A single fix for an early boot warning caused by invoking this_cpu_has()
before SMP initialization.

Thanks,

	tglx

------------------>
Sai Praneeth (1):
      x86/mm: Fix bogus warning during EFI bootup, use boot_cpu_has() instead of this_cpu_has() in build_cr3_noflush()


 arch/x86/include/asm/tlbflush.h | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/arch/x86/include/asm/tlbflush.h b/arch/x86/include/asm/tlbflush.h
index 84137c22fdfa..6690cd3fc8b1 100644
--- a/arch/x86/include/asm/tlbflush.h
+++ b/arch/x86/include/asm/tlbflush.h
@@ -131,7 +131,12 @@ static inline unsigned long build_cr3(pgd_t *pgd, u16 asid)
 static inline unsigned long build_cr3_noflush(pgd_t *pgd, u16 asid)
 {
 	VM_WARN_ON_ONCE(asid > MAX_ASID_AVAILABLE);
-	VM_WARN_ON_ONCE(!this_cpu_has(X86_FEATURE_PCID));
+	/*
+	 * Use boot_cpu_has() instead of this_cpu_has() as this function
+	 * might be called during early boot. This should work even after
+	 * boot because all CPU's the have same capabilities:
+	 */
+	VM_WARN_ON_ONCE(!boot_cpu_has(X86_FEATURE_PCID));
 	return __sme_pa(pgd) | kern_pcid(asid) | CR3_NOFLUSH;
 }