--- /dev/null
+From jcliburn@hogchain.net Sat Nov 24 11:23:59 2007
+From: Luca Tettamanti <kronos.it@gmail.com>
+Date: Sat, 24 Nov 2007 13:15:18 -0600
+Subject: atl1: disable broken 64-bit DMA
+To: greg@kroah.com, chrisw@sous-sol.org
+Cc: csnook@redhat.com, kronos.it@gmail.com, linux-kernel@vger.kernel.org, stable@kernel.org
+Message-ID: <20071124191518.GA3672@osprey.hogchain.net>
+Content-Disposition: inline
+
+From: Luca Tettamanti <kronos.it@gmail.com>
+
+atl1: disable broken 64-bit DMA
+
+[ Upstream commit: 5f08e46b621a769e52a9545a23ab1d5fb2aec1d4 ]
+
+The L1 network chip can DMA to 64-bit addresses, but multiple descriptor
+rings share a single register for the high 32 bits of their address, so
+only a single, aligned, 4 GB physical address range can be used at a time.
+As a result, we need to confine the driver to a 32-bit DMA mask, otherwise
+we see occasional data corruption errors in systems containing 4 or more
+gigabytes of RAM.
+
+Signed-off-by: Luca Tettamanti <kronos.it@gmail.com>
+Signed-off-by: Jay Cliburn <jacliburn@bellsouth.net>
+Acked-by: Chris Snook <csnook@redhat.com>
+Signed-off-by: Jeff Garzik <jeff@garzik.org>
+Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
+
+
+---
+ drivers/net/atl1/atl1_main.c | 25 +++++++++++++------------
+ 1 file changed, 13 insertions(+), 12 deletions(-)
+
+--- a/drivers/net/atl1/atl1_main.c
++++ b/drivers/net/atl1/atl1_main.c
+@@ -2097,21 +2097,26 @@ static int __devinit atl1_probe(struct p
+ struct net_device *netdev;
+ struct atl1_adapter *adapter;
+ static int cards_found = 0;
+- bool pci_using_64 = true;
+ int err;
+
+ err = pci_enable_device(pdev);
+ if (err)
+ return err;
+
+- err = pci_set_dma_mask(pdev, DMA_64BIT_MASK);
++ /*
++ * The atl1 chip can DMA to 64-bit addresses, but it uses a single
++ * shared register for the high 32 bits, so only a single, aligned,
++ * 4 GB physical address range can be used at a time.
++ *
++ * Supporting 64-bit DMA on this hardware is more trouble than it's
++ * worth. It is far easier to limit to 32-bit DMA than update
++ * various kernel subsystems to support the mechanics required by a
++ * fixed-high-32-bit system.
++ */
++ err = pci_set_dma_mask(pdev, DMA_32BIT_MASK);
+ if (err) {
+- err = pci_set_dma_mask(pdev, DMA_32BIT_MASK);
+- if (err) {
+- dev_err(&pdev->dev, "no usable DMA configuration\n");
+- goto err_dma;
+- }
+- pci_using_64 = false;
++ dev_err(&pdev->dev, "no usable DMA configuration\n");
++ goto err_dma;
+ }
+ /* Mark all PCI regions associated with PCI device
+ * pdev as being reserved by owner atl1_driver_name
+@@ -2176,7 +2181,6 @@ static int __devinit atl1_probe(struct p
+
+ netdev->ethtool_ops = &atl1_ethtool_ops;
+ adapter->bd_number = cards_found;
+- adapter->pci_using_64 = pci_using_64;
+
+ /* setup the private structure */
+ err = atl1_sw_init(adapter);
+@@ -2193,9 +2197,6 @@ static int __devinit atl1_probe(struct p
+ */
+ /* netdev->features |= NETIF_F_TSO; */
+
+- if (pci_using_64)
+- netdev->features |= NETIF_F_HIGHDMA;
+-
+ netdev->features |= NETIF_F_LLTX;
+
+ /*
--- /dev/null
+From jack+f-061107@ucw.cz Tue Nov 6 03:26:18 2007
+From: Christian Borntraeger <borntraeger@de.ibm.com>
+Date: Tue, 6 Nov 2007 12:26:15 +0100
+Subject: rd: fix data corruption on memory pressure
+Subject: Re: Future of Linux 2.6.22.y series
+To: Greg Kroah-Hartman <gregkh@suse.de>
+Cc: linux-kernel@vger.kernel.org, Christian Borntraeger <borntraeger@de.ibm.com>
+Message-ID: <20071106112615.GG32704@atrey.karlin.mff.cuni.cz>
+Content-Disposition: inline
+
+From: Christian Borntraeger <borntraeger@de.ibm.com>
+
+commit 5d0360ee96a5ef953dbea45873c2a8c87e77d59b upstream.
+
+We have seen ramdisk based install systems, where some pages of mapped
+libraries and programs were suddendly zeroed under memory pressure. This
+should not happen, as the ramdisk avoids freeing its pages by keeping
+them dirty all the time.
+
+It turns out that there is a case, where the VM makes a ramdisk page
+clean, without telling the ramdisk driver. On memory pressure
+shrink_zone runs and it starts to run shrink_active_list. There is a
+check for buffer_heads_over_limit, and if true, pagevec_strip is called.
+pagevec_strip calls try_to_release_page. If the mapping has no
+releasepage callback, try_to_free_buffers is called. try_to_free_buffers
+has now a special logic for some file systems to make a dirty page
+clean, if all buffers are clean. Thats what happened in our test case.
+
+The simplest solution is to provide a noop-releasepage callback for the
+ramdisk driver. This avoids try_to_free_buffers for ramdisk pages.
+
+Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
+Signed-off-by: Jan Kara <jack@suse.cz>
+Acked-by: Nick Piggin <npiggin@suse.de>
+Cc: "Eric W. Biederman" <ebiederm@xmission.com>
+Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
+Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
+Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
+
+
+---
+ drivers/block/rd.c | 13 +++++++++++++
+ 1 file changed, 13 insertions(+)
+
+--- a/drivers/block/rd.c
++++ b/drivers/block/rd.c
+@@ -189,6 +189,18 @@ static int ramdisk_set_page_dirty(struct
+ return 0;
+ }
+
++/*
++ * releasepage is called by pagevec_strip/try_to_release_page if
++ * buffers_heads_over_limit is true. Without a releasepage function
++ * try_to_free_buffers is called instead. That can unset the dirty
++ * bit of our ram disk pages, which will be eventually freed, even
++ * if the page is still in use.
++ */
++static int ramdisk_releasepage(struct page *page, gfp_t dummy)
++{
++ return 0;
++}
++
+ static const struct address_space_operations ramdisk_aops = {
+ .readpage = ramdisk_readpage,
+ .prepare_write = ramdisk_prepare_write,
+@@ -196,6 +208,7 @@ static const struct address_space_operat
+ .writepage = ramdisk_writepage,
+ .set_page_dirty = ramdisk_set_page_dirty,
+ .writepages = ramdisk_writepages,
++ .releasepage = ramdisk_releasepage,
+ };
+
+ static int rd_blkdev_pagecache_IO(int rw, struct bio_vec *vec, sector_t sector,
projects / thirdparty / kernel / stable-queue.git / commitdiff
