Patch "powerpc/64: Invalidate process table caching after setting process table" has been added to the 4.9-stable tree

Patch "powerpc/64: Invalidate process table caching after setting process table" has been added to the 4.9-stable tree

[gregkh]

This is a note to let you know that I've just added the patch titled

    powerpc/64: Invalidate process table caching after setting process table

to the 4.9-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     powerpc-64-invalidate-process-table-caching-after-setting-process-table.patch
and it can be found in the queue-4.9 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From foo@baz Tue Dec 12 13:26:17 CET 2017
From: Paul Mackerras <paulus@ozlabs.org>
Date: Mon, 27 Feb 2017 14:32:41 +1100
Subject: powerpc/64: Invalidate process table caching after setting process table

From: Paul Mackerras <paulus@ozlabs.org>


[ Upstream commit 7a70d7288c926ae88e0c773fbb506aa374e99c2d ]

The POWER9 MMU reads and caches entries from the process table.
When we kexec from one kernel to another, the second kernel sets
its process table pointer but doesn't currently do anything to
make the CPU invalidate any cached entries from the old process table.
This adds a tlbie (TLB invalidate entry) instruction with parameters
to invalidate caching of the process table after the new process
table is installed.

Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 arch/powerpc/mm/pgtable-radix.c |    4 ++++
 1 file changed, 4 insertions(+)

--- a/arch/powerpc/mm/pgtable-radix.c
+++ b/arch/powerpc/mm/pgtable-radix.c
@@ -173,6 +173,10 @@ redo:
 	 */
 	register_process_table(__pa(process_tb), 0, PRTB_SIZE_SHIFT - 12);
 	pr_info("Process table %p and radix root for kernel: %p\n", process_tb, init_mm.pgd);
+	asm volatile("ptesync" : : : "memory");
+	asm volatile(PPC_TLBIE_5(%0,%1,2,1,1) : :
+		     "r" (TLBIEL_INVAL_SET_LPID), "r" (0));
+	asm volatile("eieio; tlbsync; ptesync" : : : "memory");
 }
 
 static void __init radix_init_partition_table(void)


Patches currently in stable-queue which might be from paulus@ozlabs.org are

queue-4.9/powerpc-64-fix-checksum-folding-in-csum_add.patch
queue-4.9/powerpc-64-invalidate-process-table-caching-after-setting-process-table.patch