Commit 1e547681 authored Jan 04, 2018 by Thomas Gleixner

x86/tlb: Drop the _GPL from the cpu_tlbstate export



The recent changes for PTI touch cpu_tlbstate from various tlb_flush
inlines. cpu_tlbstate is exported as GPL symbol, so this causes a
regression when building out of tree drivers for certain graphics cards.

Aside of that the export was wrong since it was introduced as it should
have been EXPORT_PER_CPU_SYMBOL_GPL().

Use the correct PER_CPU export and drop the _GPL to restore the previous
state which allows users to utilize the cards they payed for.

As always I'm really thrilled to make this kind of change to support the
#friends (or however the hot hashtag of today is spelled) from that closet
sauce graphics corp.

Fixes: 1e02ce4c ("x86: Store a per-cpu shadow copy of CR4")
Fixes: 6fd166aa ("x86/mm: Use/Fix PCID to optimize user/kernel switches")
Reported-by: Kees Cook <keescook@google.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: stable@vger.kernel.org

parent 42f3bdc5

arch/x86/mm/init.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -870,7 +870,7 @@ __visible DEFINE_PER_CPU_SHARED_ALIGNED(struct tlb_state, cpu_tlbstate) = {
		.next_asid = 1,
		.cr4 = ~0UL, /* fail hard if we screw up cr4 shadow initialization */
		};
		EXPORT_SYMBOL_GPL(cpu_tlbstate);
		EXPORT_PER_CPU_SYMBOL(cpu_tlbstate);

		void update_cache_mode_entry(unsigned entry, enum page_cache_mode cache)
		{

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