Patch "Revert "MIPS: Avoid pipeline stalls on some MIPS32R2 cores."" has been added to the 4.0-stable tree

[<gregkh@linuxfoundation.org>]

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

    Revert "MIPS: Avoid pipeline stalls on some MIPS32R2 cores."

to the 4.0-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:
     revert-mips-avoid-pipeline-stalls-on-some-mips32r2-cores.patch
and it can be found in the queue-4.0 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 ralf@linux-mips.org  Fri May  8 16:40:22 2015
From: Ralf Baechle <ralf@linux-mips.org>
Date: Wed, 25 Mar 2015 13:18:27 +0100
Subject: Revert "MIPS: Avoid pipeline stalls on some MIPS32R2 cores."
To: stable@vger.kernel.org
Message-ID: <ab0cb06de61240d9b5449cc968f2a96ea2aae1ac.1431087908.git.ralf@linux-mips.org>


Commit 9eaffa84a8a46adab065c983401fc9d5949c958f upstream.

For a discussion, see http://patchwork.linux-mips.org/patch/9539/.

This reverts commit 625c0a21700bdb90844d926a1508a17a77e369c9.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 arch/mips/mm/tlbex.c |   21 ++-------------------
 1 file changed, 2 insertions(+), 19 deletions(-)

--- a/arch/mips/mm/tlbex.c
+++ b/arch/mips/mm/tlbex.c
@@ -501,26 +501,9 @@ static void build_tlb_write_entry(u32 **
 	case tlb_indexed: tlbw = uasm_i_tlbwi; break;
 	}
 
-	if (cpu_has_mips_r2_exec_hazard) {
-		/*
-		 * The architecture spec says an ehb is required here,
-		 * but a number of cores do not have the hazard and
-		 * using an ehb causes an expensive pipeline stall.
-		 */
-		switch (current_cpu_type()) {
-		case CPU_M14KC:
-		case CPU_74K:
-		case CPU_1074K:
-		case CPU_PROAPTIV:
-		case CPU_P5600:
-		case CPU_M5150:
-		case CPU_QEMU_GENERIC:
-			break;
-
-		default:
+	if (cpu_has_mips_r2_r6) {
+		if (cpu_has_mips_r2_exec_hazard)
 			uasm_i_ehb(p);
-			break;
-		}
 		tlbw(p);
 		return;
 	}


Patches currently in stable-queue which might be from ralf@linux-mips.org are

queue-4.0/mips-octeon-remove-udelay-causing-huge-irq-latency.patch
queue-4.0/mips-makefile-fix-mips-ase-detection-code.patch
queue-4.0/mips-r4kcache-use-correct-base-register-for-mips-r6-cache-flushes.patch
queue-4.0/mips-fix-cpu_has_mips_r2_exec_hazard.patch
queue-4.0/mips-ralink-fix-bad-config-symbol-in-pci-makefile.patch
queue-4.0/revert-mips-remove-race-window-in-page-fault-handling.patch
queue-4.0/mips-fix-race-condition-in-lazy-cache-flushing.patch
queue-4.0/mips-bcm63xx-move-bcm63xx_gpio_init-to-bcm63xx_register_devices.patch
queue-4.0/mips-octeon-delete-override-of-cpu_has_mips_r2_exec_hazard.patch
queue-4.0/mips-asm-spinlock-fix-addiu-instruction-for-r10000_llsc_war-case.patch
queue-4.0/mips-kconfig-disable-smp-cps-for-64-bit.patch
queue-4.0/mips-bcm47xx-fix-detecting-microsoft-mn-700-asus-wl500g.patch
queue-4.0/mips-octeon-use-correct-csr-to-soft-reset.patch
queue-4.0/revert-mips-avoid-pipeline-stalls-on-some-mips32r2-cores.patch
queue-4.0/mips-octeon-dma-octeon-fix-ohci-usb-config-check.patch
queue-4.0/mips-octeon-fix-pci-interrupt-mapping-for-d-link-dsr-1000n.patch
queue-4.0/mips-kconfig-fix-typo-for-the-r2-to-r6-emulator-kernel-parameter.patch
queue-4.0/ssb-fix-kconfig-dependencies.patch
queue-4.0/mips-kernel-entry.s-set-correct-isa-level-for-mips_ihb.patch
queue-4.0/mips-netlogic-fix-for-sata-phy-init.patch
queue-4.0/mips-ralink-add-missing-symbol-for-ralink_ill_acc.patch
queue-4.0/mips-asm-elf-set-o32-default-fpu-flags.patch
queue-4.0/mips-smp-cps-cpu_set-fpu-mask-if-fpu-present.patch