From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932451Ab1DMQJ7 (ORCPT ); Wed, 13 Apr 2011 12:09:59 -0400 Received: from kroah.org ([198.145.64.141]:54259 "EHLO coco.kroah.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757699Ab1DMPzP (ORCPT ); Wed, 13 Apr 2011 11:55:15 -0400 X-Mailbox-Line: From gregkh@clark.kroah.org Wed Apr 13 08:51:44 2011 Message-Id: <20110413155144.687388683@clark.kroah.org> User-Agent: quilt/0.48-16.4 Date: Wed, 13 Apr 2011 08:50:40 -0700 From: Greg KH To: linux-kernel@vger.kernel.org, stable@kernel.org Cc: stable-review@kernel.org, torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, Olaf Hering , Haiyang Zhang , Hank Janssen Subject: [16/74] staging: hv: use sync_bitops when interacting with the hypervisor In-Reply-To: <20110413155406.GA22568@kroah.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 2.6.32-longterm review patch. If anyone has any objections, please let us know. ------------------ From: Olaf Hering commit 22356585712d1ff08fbfed152edd8b386873b238 upstream. Locking is required when tweaking bits located in a shared page, use the sync_ version of bitops. Without this change vmbus_on_event() will miss events and as a result, vmbus_isr() will not schedule the receive tasklet. [Backported to 2.6.32 stable kernel by Haiyang Zhang ] Signed-off-by: Olaf Hering Acked-by: Haiyang Zhang Acked-by: Hank Janssen Signed-off-by: Greg Kroah-Hartman --- drivers/staging/hv/Channel.c | 8 ++++---- drivers/staging/hv/Connection.c | 6 ++++-- drivers/staging/hv/Vmbus.c | 2 +- drivers/staging/hv/VmbusPrivate.h | 1 + 4 files changed, 10 insertions(+), 7 deletions(-) --- a/drivers/staging/hv/Channel.c +++ b/drivers/staging/hv/Channel.c @@ -75,14 +75,14 @@ static void VmbusChannelSetEvent(struct if (Channel->OfferMsg.MonitorAllocated) { /* Each u32 represents 32 channels */ - set_bit(Channel->OfferMsg.ChildRelId & 31, + sync_set_bit(Channel->OfferMsg.ChildRelId & 31, (unsigned long *) gVmbusConnection.SendInterruptPage + (Channel->OfferMsg.ChildRelId >> 5)); monitorPage = gVmbusConnection.MonitorPages; monitorPage++; /* Get the child to parent monitor page */ - set_bit(Channel->MonitorBit, + sync_set_bit(Channel->MonitorBit, (unsigned long *)&monitorPage->TriggerGroup [Channel->MonitorGroup].Pending); @@ -102,7 +102,7 @@ static void VmbusChannelClearEvent(struc if (Channel->OfferMsg.MonitorAllocated) { /* Each u32 represents 32 channels */ - clear_bit(Channel->OfferMsg.ChildRelId & 31, + sync_clear_bit(Channel->OfferMsg.ChildRelId & 31, (unsigned long *)gVmbusConnection.SendInterruptPage + (Channel->OfferMsg.ChildRelId >> 5)); @@ -110,7 +110,7 @@ static void VmbusChannelClearEvent(struc (struct hv_monitor_page *)gVmbusConnection.MonitorPages; monitorPage++; /* Get the child to parent monitor page */ - clear_bit(Channel->MonitorBit, + sync_clear_bit(Channel->MonitorBit, (unsigned long *)&monitorPage->TriggerGroup [Channel->MonitorGroup].Pending); } --- a/drivers/staging/hv/Connection.c +++ b/drivers/staging/hv/Connection.c @@ -284,7 +284,9 @@ void VmbusOnEvents(void) for (dword = 0; dword < maxdword; dword++) { if (recvInterruptPage[dword]) { for (bit = 0; bit < 32; bit++) { - if (test_and_clear_bit(bit, (unsigned long *)&recvInterruptPage[dword])) { + if (sync_test_and_clear_bit(bit, + (unsigned long *) + &recvInterruptPage[dword])) { relid = (dword << 5) + bit; DPRINT_DBG(VMBUS, "event detected for relid - %d", relid); @@ -329,7 +331,7 @@ int VmbusSetEvent(u32 childRelId) DPRINT_ENTER(VMBUS); /* Each u32 represents 32 channels */ - set_bit(childRelId & 31, + sync_set_bit(childRelId & 31, (unsigned long *)gVmbusConnection.SendInterruptPage + (childRelId >> 5)); --- a/drivers/staging/hv/Vmbus.c +++ b/drivers/staging/hv/Vmbus.c @@ -254,7 +254,7 @@ static int VmbusOnISR(struct hv_driver * event = (union hv_synic_event_flags *)page_addr + VMBUS_MESSAGE_SINT; /* Since we are a child, we only need to check bit 0 */ - if (test_and_clear_bit(0, (unsigned long *) &event->Flags32[0])) { + if (sync_test_and_clear_bit(0, (unsigned long *) &event->Flags32[0])) { DPRINT_DBG(VMBUS, "received event %d", event->Flags32[0]); ret |= 0x2; } --- a/drivers/staging/hv/VmbusPrivate.h +++ b/drivers/staging/hv/VmbusPrivate.h @@ -32,6 +32,7 @@ #include "ChannelInterface.h" #include "RingBuffer.h" #include +#include /*