From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Kamal Mostafa To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Alexis Dambricourt , Paolo Bonzini , Kamal Mostafa Subject: [PATCH 4.2.y-ckt 257/305] KVM: MTRR: fix fixed MTRR segment look up Date: Fri, 15 Jan 2016 16:01:11 -0800 Message-Id: <1452902519-2754-258-git-send-email-kamal@canonical.com> In-Reply-To: <1452902519-2754-1-git-send-email-kamal@canonical.com> References: <1452902519-2754-1-git-send-email-kamal@canonical.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: 4.2.8-ckt2 -stable review patch. If anyone has any objections, please let me know. ---8<------------------------------------------------------------ From: Alexis Dambricourt commit a7f2d7865720ff13d5b0f2a3bb1fd80dc3d7a73f upstream. This fixes the slow-down of VM running with pci-passthrough, since some MTRR range changed from MTRR_TYPE_WRBACK to MTRR_TYPE_UNCACHABLE. Memory in the 0K-640K range was incorrectly treated as uncacheable. Fixes: f7bfb57b3e89ff89c0da9f93dedab89f68d6ca27 Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=107561 Signed-off-by: Alexis Dambricourt [Use correct BZ for "Fixes" annotation. - Paolo] Signed-off-by: Paolo Bonzini Signed-off-by: Kamal Mostafa --- arch/x86/kvm/mtrr.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/x86/kvm/mtrr.c b/arch/x86/kvm/mtrr.c index 9e8bf13..adc54e1 100644 --- a/arch/x86/kvm/mtrr.c +++ b/arch/x86/kvm/mtrr.c @@ -267,7 +267,7 @@ static int fixed_mtrr_addr_to_seg(u64 addr) for (seg = 0; seg < seg_num; seg++) { mtrr_seg = &fixed_seg_table[seg]; - if (mtrr_seg->start >= addr && addr < mtrr_seg->end) + if (mtrr_seg->start <= addr && addr < mtrr_seg->end) return seg; } -- 1.9.1