Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
From:   Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To:     linux-kernel@vger.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        stable@vger.kernel.org, Meelis Roos <mroos@linux.ee>,
        James Clarke <jrtc27@jrtc27.com>,
        "David S. Miller" <davem@davemloft.net>
Subject: [PATCH 4.14 21/69] sparc64: Fix regression in non-hypervisor TLB flush xcall
Date:   Fri,  7 Jun 2019 17:39:02 +0200
Message-Id: <20190607153850.958090082@linuxfoundation.org>
In-Reply-To: <20190607153848.271562617@linuxfoundation.org>
References: <20190607153848.271562617@linuxfoundation.org>
User-Agent: quilt/0.66
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

From: James Clarke <jrtc27@jrtc27.com>

commit d3c976c14ad8af421134c428b0a89ff8dd3bd8f8 upstream.

Previously, %g2 would end up with the value PAGE_SIZE, but after the
commit mentioned below it ends up with the value 1 due to being reused
for a different purpose. We need it to be PAGE_SIZE as we use it to step
through pages in our demap loop, otherwise we set different flags in the
low 12 bits of the address written to, thereby doing things other than a
nucleus page flush.

Fixes: a74ad5e660a9 ("sparc64: Handle extremely large kernel TLB range flushes more gracefully.")
Reported-by: Meelis Roos <mroos@linux.ee>
Tested-by: Meelis Roos <mroos@linux.ee>
Signed-off-by: James Clarke <jrtc27@jrtc27.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 arch/sparc/mm/ultra.S |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

--- a/arch/sparc/mm/ultra.S
+++ b/arch/sparc/mm/ultra.S
@@ -587,7 +587,7 @@ xcall_flush_tlb_kernel_range:	/* 44 insn
 	sub		%g7, %g1, %g3
 	srlx		%g3, 18, %g2
 	brnz,pn		%g2, 2f
-	 add		%g2, 1, %g2
+	 sethi		%hi(PAGE_SIZE), %g2
 	sub		%g3, %g2, %g3
 	or		%g1, 0x20, %g1		! Nucleus
 1:	stxa		%g0, [%g1 + %g3] ASI_DMMU_DEMAP
@@ -751,7 +751,7 @@ __cheetah_xcall_flush_tlb_kernel_range:
 	sub		%g7, %g1, %g3
 	srlx		%g3, 18, %g2
 	brnz,pn		%g2, 2f
-	 add		%g2, 1, %g2
+	 sethi		%hi(PAGE_SIZE), %g2
 	sub		%g3, %g2, %g3
 	or		%g1, 0x20, %g1		! Nucleus
 1:	stxa		%g0, [%g1 + %g3] ASI_DMMU_DEMAP