- 01 Oct, 2010 2 commits
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Greg Kroah-Hartman authored
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James Dingwall authored
Correctly name the irq_chip structure to fix an immediate failure when booting as a xen pv_ops guest with a NULL pointer exception. The missing 'x' was introduced in commit [fb412a17] applied to 2.6.3[25]-stable trees. The commit to mainline was [aaca4964] which did not have the problem. Signed-off-by:
James Dingwall <james@dingwall.me.uk> Reported-by:
Pawel Zuzelski <pawelz@pld-linux.org> Tested-by:
Greg Kroah-Hartman <gregkh@suse.de>
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- 27 Sep, 2010 38 commits
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Greg Kroah-Hartman authored
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H. Peter Anvin authored
commit 113fc5a6 upstream. [ Backport to .32 by Tomáš Janoušek <tomi@nomi.cz> ] xchg() and cmpxchg() modify their memory operands, not merely read them. For some versions of gcc the "memory" clobber has apparently dealt with the situation, but not for all. Originally-by:
Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by:
H. Peter Anvin <hpa@zytor.com> Cc: Glauber Costa <glommer@redhat.com> Cc: Avi Kivity <avi@redhat.com> Cc: Peter Palfrader <peter@palfrader.org> Cc: Greg KH <gregkh@suse.de> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: Zachary Amsden <zamsden@redhat.com> Cc: Marcelo Tosatti <mtosatti@redhat.com> LKML-Reference: <4C4F7277.8050306@zytor.com> Signed-off-by:
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Michael Cree authored
commit 3e073367 upstream. When compiling alpha generic build get errors such as: arch/alpha/kernel/err_marvel.c: In function ‘marvel_print_err_cyc’: arch/alpha/kernel/err_marvel.c:119: error: format ‘%ld’ expects type ‘long int’, but argument 6 has type ‘u64’ Replaced a number of %ld format specifiers with %lld since u64 is unsigned long long. Signed-off-by:
Michael Cree <mcree@orcon.net.nz> Signed-off-by:
Matt Turner <mattst88@gmail.com> Signed-off-by:
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Ben Hutchings authored
commit d831692a upstream. SIS 760 is listed in the device tables for both amd64-agp and sis-agp. amd64-agp is apparently preferable since it has workarounds for some BIOS misconfigurations that sis-agp doesn't handle. Signed-off-by:
Ben Hutchings <ben@decadent.org.uk> Signed-off-by:
Dave Airlie <airlied@redhat.com> Signed-off-by:
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Ralf Baechle authored
commit 3d45285d upstream. The M3 workaround needs to cmpare the region and VPN2 fields only. Signed-off-by:
Ralf Baechle <ralf@linux-mips.org> Signed-off-by:
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Bartlomiej Zolnierkiewicz authored
commit 750e519d upstream. PDC2026x chipsets need the same treatment as PDC20246 one. This is completely untested but will hopefully fix UDMA issues that people have been reporting against pata_pdc202xx_old for the last couple of years. Signed-off-by:
Bartlomiej Zolnierkiewicz <bzolnier@gmail.com> Signed-off-by:
Jeff Garzik <jgarzik@redhat.com> Signed-off-by:
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Bartlomiej Zolnierkiewicz authored
commit a75032e8 upstream. On Monday 04 January 2010 02:30:24 pm Russell King wrote: > Found the problem - getting rid of the read of the alt status register > after the command has been written fixes the UDMA CRC errors on write: > > @@ -676,7 +676,8 @@ void ata_sff_exec_command(struct ata_port *ap, const struct > ata_taskfile *tf) > DPRINTK("ata%u: cmd 0x%X\n", ap->print_id, tf->command); > > iowrite8(tf->command, ap->ioaddr.command_addr); > - ata_sff_pause(ap); > + ndelay(400); > +// ata_sff_pause(ap); > } > EXPORT_SYMBOL_GPL(ata_sff_exec_command); > > > This rather makes sense. The PDC20247 handles the UDMA part of the > protocol. It has no way to tell the PDC20246 to wait while it suspends > UDMA, so that a normal register access can take place - the 246 ploughs > on with the register access without any regard to the state of the 247. > > If the drive immediately starts the UDMA protocol after a write to the > command register (as it probably will for the DMA WRITE command), then > we'll be accessing the taskfile in the middle of the UDMA setup, which > can't be good. It's certainly a violation of the ATA specs. Fix it by adding custom ->sff_exec_command method for UDMA33 chipsets. Debugged-by:
Russell King <rmk@arm.linux.org.uk> Signed-off-by:
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Ralf Baechle authored
commit 5808184f upstream. This is needed for the fix of the M3 workaround. Signed-off-by:
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Ben Hutchings authored
commit 8faf2e6c upstream. Several MIPS platforms don't set pci_controller::io_map_base for their PCI bridges. This results in a panic in pci_iomap(). (The panic is conditional on CONFIG_PCI_DOMAINS, but that is now enabled for all PCI MIPS systems.) Signed-off-by:
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David Daney authored
commit f2a68272 upstream. For 64-bit, we must use DADDU and DSUBU. Signed-off-by:
David Daney <ddaney@caviumnetworks.com> To: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/1483/Signed-off-by:
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Dmitry Torokhov authored
commit 15e184af upstream. Input core displays capabilities bitmasks in form of one or more longs printed in hex form and separated by spaces. Unfortunately it does not work well for 32-bit applications running on 64-bit kernels since applications expect that number is "worth" only 32 bits when kernel advances by 64 bits. Fix that by ensuring that output produced for compat tasks uses 32-bit units. Reported-and-tested-by:
Michael Tokarev <mjt@tls.msk.ru> Signed-off-by:
Dmitry Torokhov <dtor@mail.ru> Signed-off-by:
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Eric Paris authored
commit ff311008 upstream. During the large inotify rewrite to fsnotify I completely dropped support for IN_ONESHOT. Reimplement that support. Signed-off-by:
Eric Paris <eparis@redhat.com> Signed-off-by:
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John W. Linville authored
commit 0f4da2d7 upstream. "hostap: Protect against initialization interrupt" (which reinstated "wireless: hostap, fix oops due to early probing interrupt") reintroduced Bug 16111. This is because hostap_pci wasn't setting dev->base_addr, which is now checked in prism2_interrupt. As a result, initialization was failing for PCI-based hostap devices. This corrects that oversight. Signed-off-by:
John W. Linville <linville@tuxdriver.com> Signed-off-by:
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Herbert Xu authored
commit 622e0ca1 upstream. When GRO produces fraglist entries, and the resulting skb hits an interface that is incapable of TSO but capable of FRAGLIST, we end up producing a bogus packet with gso_size non-zero. This was reported in the field with older versions of KVM that did not set the TSO bits on tuntap. This patch fixes that. Reported-by:
Igor Zhang <yugzhang@redhat.com> Signed-off-by:
Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by:
David S. Miller <davem@davemloft.net> Signed-off-by:
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Aurelien Jarno authored
commit 66f49121 upstream. Since commit 98962465 ("nohz: Prevent clocksource wrapping during idle"), the CPU of an R2D board never goes to idle. This commit assumes that mult and shift are assigned before the clocksource is registered. As a consequence the safe maximum sleep time is negative and the CPU never goes into idle. This patch fixes the problem by moving mult and shift initialization from sh_tmu_clocksource_enable() to sh_tmu_register_clocksource(). Signed-off-by:
Aurelien Jarno <aurelien@aurel32.net> Signed-off-by:
Paul Mundt <lethal@linux-sh.org> Signed-off-by:
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Peter Oberparleiter authored
commit cffab6bc upstream. Partition boundary calculation fails for DASD FBA disks under the following conditions: - disk is formatted with CMS FORMAT with a blocksize of more than 512 bytes - all of the disk is reserved to a single CMS file using CMS RESERVE - the disk is accessed using the DIAG mode of the DASD driver Under these circumstances, the partition detection code tries to read the CMS label block containing partition-relevant information from logical block offset 1, while it is in fact located at physical block offset 1. Fix this problem by using the correct CMS label block location depending on the device type as determined by the DASD SENSE ID information. Signed-off-by:
Peter Oberparleiter <peter.oberparleiter@de.ibm.com> Signed-off-by:
Martin Schwidefsky <schwidefsky@de.ibm.com> [bwh: Adjust for 2.6.32] Signed-off-by:
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Jussi Kivilinna authored
commit 7f29a3ba upstream. Setting new MAC address only worked when device was set to promiscuous mode. Fix MAC address by writing new address to device using undocumented command AX_CMD_READ_NODE_ID+1. Patch is tested with AX88772 device. Signed-off-by:
Jussi Kivilinna <jussi.kivilinna@mbnet.fi> Acked-by:
David Hollis <dhollis@davehollis.com> Signed-off-by:
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Ben Hutchings authored
commit b0cf4dfb upstream. The driver attempts to select an IRQ for the NIC automatically by testing which of the supported IRQs are available and then probing each available IRQ with probe_irq_{on,off}(). There are obvious race conditions here, besides which: 1. The test for availability is done by passing a NULL handler, which now always returns -EINVAL, thus the device cannot be opened: <http://bugs.debian.org/566522> 2. probe_irq_off() will report only the first ISA IRQ handled, potentially leading to a false negative. There was another bug that meant it ignored all error codes from request_irq() except -EBUSY, so it would 'succeed' despite this (possibly causing conflicts with other ISA devices). This was fixed by ab08999d 'WARNING: some request_irq() failures ignored in el2_open()', which exposed bug 1. This patch: 1. Replaces the use of probe_irq_{on,off}() with a real interrupt handler 2. Adds a delay before checking the interrupt-seen flag 3. Disables interrupts on all failure paths 4. Distinguishes error codes from the second request_irq() call, consistently with the first Compile-tested only. Signed-off-by:
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Vlad Yasevich authored
commit 4bdab433 upstream. sctp_packet_config() is called when getting the packet ready for appending of chunks. The function should not touch the current state, since it's possible to ping-pong between two transports when sending, and that can result packet corruption followed by skb overlfow crash. Reported-by:
Thomas Dreibholz <dreibh@iem.uni-due.de> Signed-off-by:
Vlad Yasevich <vladislav.yasevich@hp.com> Signed-off-by:
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Daniel J Blueman authored
commit f362b732 upstream. Using a program like the following: #include <stdlib.h> #include <unistd.h> #include <sys/types.h> #include <sys/wait.h> int main() { id_t id; siginfo_t infop; pid_t res; id = fork(); if (id == 0) { sleep(1); exit(0); } kill(id, SIGSTOP); alarm(1); waitid(P_PID, id, &infop, WCONTINUED); return 0; } to call waitid() on a stopped process results in access to the child task's credentials without the RCU read lock being held - which may be replaced in the meantime - eliciting the following warning: =================================================== [ INFO: suspicious rcu_dereference_check() usage. ] --------------------------------------------------- kernel/exit.c:1460 invoked rcu_dereference_check() without protection! other info that might help us debug this: rcu_scheduler_active = 1, debug_locks = 1 2 locks held by waitid02/22252: #0: (tasklist_lock){.?.?..}, at: [<ffffffff81061ce5>] do_wait+0xc5/0x310 #1: (&(&sighand->siglock)->rlock){-.-...}, at: [<ffffffff810611da>] wait_consider_task+0x19a/0xbe0 stack backtrace: Pid: 22252, comm: waitid02 Not tainted 2.6.35-323cd+ #3 Call Trace: [<ffffffff81095da4>] lockdep_rcu_dereference+0xa4/0xc0 [<ffffffff81061b31>] wait_consider_task+0xaf1/0xbe0 [<ffffffff81061d15>] do_wait+0xf5/0x310 [<ffffffff810620b6>] sys_waitid+0x86/0x1f0 [<ffffffff8105fce0>] ? child_wait_callback+0x0/0x70 [<ffffffff81003282>] system_call_fastpath+0x16/0x1b This is fixed by holding the RCU read lock in wait_task_continued() to ensure that the task's current credentials aren't destroyed between us reading the cred pointer and us reading the UID from those credentials. Furthermore, protect wait_task_stopped() in the same way. We don't need to keep holding the RCU read lock once we've read the UID from the credentials as holding the RCU read lock doesn't stop the target task from changing its creds under us - so the credentials may be outdated immediately after we've read the pointer, lock or no lock. Signed-off-by:
Daniel J Blueman <daniel.blueman@gmail.com> Signed-off-by:
David Howells <dhowells@redhat.com> Acked-by:
Paul E. McKenney <paulmck@linux.vnet.ibm.com> Acked-by:
Oleg Nesterov <oleg@redhat.com> Signed-off-by:
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Luck, Tony authored
commit 8ca3eb08 upstream. pa-risc and ia64 have stacks that grow upwards. Check that they do not run into other mappings. By making VM_GROWSUP 0x0 on architectures that do not ever use it, we can avoid some unpleasant #ifdefs in check_stack_guard_page(). Signed-off-by:
Tony Luck <tony.luck@intel.com> Signed-off-by:
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Mel Gorman authored
commit 72853e29 upstream. When allocating a page, the system uses NR_FREE_PAGES counters to determine if watermarks would remain intact after the allocation was made. This check is made without interrupts disabled or the zone lock held and so is race-prone by nature. Unfortunately, when pages are being freed in batch, the counters are updated before the pages are added on the list. During this window, the counters are misleading as the pages do not exist yet. When under significant pressure on systems with large numbers of CPUs, it's possible for processes to make progress even though they should have been stalled. This is particularly problematic if a number of the processes are using GFP_ATOMIC as the min watermark can be accidentally breached and in extreme cases, the system can livelock. This patch updates the counters after the pages have been added to the list. This makes the allocator more cautious with respect to preserving the watermarks and mitigates livelock possibilities. [akpm@linux-foundation.org: avoid modifying incoming args] Signed-off-by:
Mel Gorman <mel@csn.ul.ie> Reviewed-by:
Rik van Riel <riel@redhat.com> Reviewed-by:
Minchan Kim <minchan.kim@gmail.com> Reviewed-by:
KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Reviewed-by:
Christoph Lameter <cl@linux.com> Reviewed-by:
KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Acked-by:
Johannes Weiner <hannes@cmpxchg.org> Signed-off-by:
Andrew Morton <akpm@linux-foundation.org> Signed-off-by:
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Christoph Lameter authored
mm: page allocator: calculate a better estimate of NR_FREE_PAGES when memory is low and kswapd is awake commit aa454840 upstream. Ordinarily watermark checks are based on the vmstat NR_FREE_PAGES as it is cheaper than scanning a number of lists. To avoid synchronization overhead, counter deltas are maintained on a per-cpu basis and drained both periodically and when the delta is above a threshold. On large CPU systems, the difference between the estimated and real value of NR_FREE_PAGES can be very high. If NR_FREE_PAGES is much higher than number of real free page in buddy, the VM can allocate pages below min watermark, at worst reducing the real number of pages to zero. Even if the OOM killer kills some victim for freeing memory, it may not free memory if the exit path requires a new page resulting in livelock. This patch introduces a zone_page_state_snapshot() function (courtesy of Christoph) that takes a slightly more accurate view of an arbitrary vmstat counter. It is used to read NR_FREE_PAGES while kswapd is awake to avoid the watermark being accidentally broken. The estimate is not perfect and may result in cache line bounces but is expected to be lighter than the IPI calls necessary to continually drain the per-cpu counters while kswapd is awake. Signed-off-by:
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Mel Gorman authored
commit 9ee493ce upstream. When under significant memory pressure, a process enters direct reclaim and immediately afterwards tries to allocate a page. If it fails and no further progress is made, it's possible the system will go OOM. However, on systems with large amounts of memory, it's possible that a significant number of pages are on per-cpu lists and inaccessible to the calling process. This leads to a process entering direct reclaim more often than it should increasing the pressure on the system and compounding the problem. This patch notes that if direct reclaim is making progress but allocations are still failing that the system is already under heavy pressure. In this case, it drains the per-cpu lists and tries the allocation a second time before continuing. Signed-off-by:
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Divy Le Ray authored
commit a6f018e3 upstream. queue restart tasklets need to be stopped after napi handlers are stopped since the latter can restart them. So stop them after stopping napi. Signed-off-by:
Divy Le Ray <divy@chelsio.com> Signed-off-by:
Brandon Philips <bphilips@suse.de> Signed-off-by:
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Nicolas Ferre authored
commit 8d2602e0 upstream. Reported-by:
Dan Liang <dan.liang@atmel.com> Signed-off-by:
Nicolas Ferre <nicolas.ferre@atmel.com> Signed-off-by:
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Michael Chan authored
commit f048fa9c upstream. The regression is caused by: commit 4327ba43 bnx2: Fix netpoll crash. If ->open() and ->close() are called multiple times, the same napi structs will be added to dev->napi_list multiple times, corrupting the dev->napi_list. This causes free_netdev() to hang during rmmod. We fix this by calling netif_napi_del() during ->close(). Also, bnx2_init_napi() must not be in the __devinit section since it is called by ->open(). Signed-off-by:
Michael Chan <mchan@broadcom.com> Signed-off-by:
Benjamin Li <benli@broadcom.com> Signed-off-by:
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Benjamin Li authored
commit 4327ba43 upstream. The bnx2 driver calls netif_napi_add() for all the NAPI structs during ->probe() time but not all of them will be used if we're not in MSI-X mode. This creates a problem for netpoll since it will poll all the NAPI structs in the dev_list whether or not they are scheduled, resulting in a crash when we access structure fields not initialized for that vector. We fix it by moving the netif_napi_add() call to ->open() after the number of IRQ vectors has been determined. Signed-off-by:
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Zhang Rui authored
commit 81074e90 upstream. Fix a win7 compability issue on Asus K50IJ. Here is the _BCM method of this laptop: Method (_BCM, 1, NotSerialized) { If (LGreaterEqual (OSFG, OSVT)) { If (LNotEqual (OSFG, OSW7)) { Store (One, BCMD) Store (GCBL (Arg0), Local0) Subtract (0x0F, Local0, LBTN) ^^^SBRG.EC0.STBR () ... } Else { DBGR (0x0B, Zero, Zero, Arg0) Store (Arg0, LBTN) ^^^SBRG.EC0.STBR () ... } } } LBTN is used to store the index of the brightness level in the _BCL. GCBL is a method that convert the percentage value to the index value. If _OSI(Windows 2009) is not disabled, LBTN is stored a percentage value which is surely beyond the end of _BCL package. http://bugzilla.kernel.org/show_bug.cgi?id=14753Signed-off-by:
Zhang Rui <rui.zhang@intel.com> Signed-off-by:
Len Brown <len.brown@intel.com> Cc: maximilian attems <max@stro.at> Cc: Paolo Ornati <ornati@gmail.com> Signed-off-by:
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Dan Rosenberg authored
commit b4aaa78f upstream. The VIAFB_GET_INFO device ioctl allows unprivileged users to read 246 bytes of uninitialized stack memory, because the "reserved" member of the viafb_ioctl_info struct declared on the stack is not altered or zeroed before being copied back to the user. This patch takes care of it. Signed-off-by:
Dan Rosenberg <dan.j.rosenberg@gmail.com> Signed-off-by:
Florian Tobias Schandinat <FlorianSchandinat@gmx.de> Signed-off-by:
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Dan Rosenberg authored
commit a122eb2f upstream. The XFS_IOC_FSGETXATTR ioctl allows unprivileged users to read 12 bytes of uninitialized stack memory, because the fsxattr struct declared on the stack in xfs_ioc_fsgetxattr() does not alter (or zero) the 12-byte fsx_pad member before copying it back to the user. This patch takes care of it. Signed-off-by:
Eric Sandeen <sandeen@redhat.com> Signed-off-by:
Alex Elder <aelder@sgi.com> Cc: dann frazier <dannf@debian.org> Signed-off-by:
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David Howells authored
commit 3d96406c upstream. Fix a bug in keyctl_session_to_parent() whereby it tries to check the ownership of the parent process's session keyring whether or not the parent has a session keyring [CVE-2010-2960]. This results in the following oops: BUG: unable to handle kernel NULL pointer dereference at 00000000000000a0 IP: [<ffffffff811ae4dd>] keyctl_session_to_parent+0x251/0x443 ... Call Trace: [<ffffffff811ae2f3>] ? keyctl_session_to_parent+0x67/0x443 [<ffffffff8109d286>] ? __do_fault+0x24b/0x3d0 [<ffffffff811af98c>] sys_keyctl+0xb4/0xb8 [<ffffffff81001eab>] system_call_fastpath+0x16/0x1b if the parent process has no session keyring. If the system is using pam_keyinit then it mostly protected against this as all processes derived from a login will have inherited the session keyring created by pam_keyinit during the log in procedure. To test this, pam_keyinit calls need to be commented out in /etc/pam.d/. Reported-by:
Tavis Ormandy <taviso@cmpxchg8b.com> Signed-off-by:
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David Howells authored
commit 9d1ac65a upstream. There's an protected access to the parent process's credentials in the middle of keyctl_session_to_parent(). This results in the following RCU warning: =================================================== [ INFO: suspicious rcu_dereference_check() usage. ] --------------------------------------------------- security/keys/keyctl.c:1291 invoked rcu_dereference_check() without protection! other info that might help us debug this: rcu_scheduler_active = 1, debug_locks = 0 1 lock held by keyctl-session-/2137: #0: (tasklist_lock){.+.+..}, at: [<ffffffff811ae2ec>] keyctl_session_to_parent+0x60/0x236 stack backtrace: Pid: 2137, comm: keyctl-session- Not tainted 2.6.36-rc2-cachefs+ #1 Call Trace: [<ffffffff8105606a>] lockdep_rcu_dereference+0xaa/0xb3 [<ffffffff811ae379>] keyctl_session_to_parent+0xed/0x236 [<ffffffff811af77e>] sys_keyctl+0xb4/0xb6 [<ffffffff81001eab>] system_call_fastpath+0x16/0x1b The code should take the RCU read lock to make sure the parents credentials don't go away, even though it's holding a spinlock and has IRQ disabled. Signed-off-by:
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Petr Tesarik authored
commit 2d2b6901 upstream. Tony's fix (f574c843) has a small bug, it incorrectly uses "r3" as a scratch register in the first of the two unlock paths ... it is also inefficient. Optimize the fast path again. Signed-off-by:
Petr Tesarik <ptesarik@suse.cz> Signed-off-by:
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Tony Luck authored
commit f574c843 upstream. When ia64 converted to using ticket locks, an inline implementation of trylock/unlock in fsys.S was missed. This was not noticed because in most circumstances it simply resulted in using the slow path because the siglock was apparently not available (under old spinlock rules). Problems occur when the ticket spinlock has value 0x0 (when first initialised, or when it wraps around). At this point the fsys.S code acquires the lock (changing the 0x0 to 0x1. If another process attempts to get the lock at this point, it will change the value from 0x1 to 0x2 (using new ticket lock rules). Then the fsys.S code will free the lock using old spinlock rules by writing 0x0 to it. From here a variety of bad things can happen. Signed-off-by:
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Dmitry Monakhov authored
commit 84a8dce2 upstream. A few functions were still modifying i_flags in a racy manner. Signed-off-by:
Dmitry Monakhov <dmonakhov@openvz.org> Signed-off-by:
"Theodore Ts'o" <tytso@mit.edu> Signed-off-by:
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Ryan Kuester authored
commit 2a1b7e57 upstream. I may have an explanation for the LSI 1068 HBA hangs provoked by ATA pass-through commands, in particular by smartctl. First, my version of the symptoms. On an LSI SAS1068E B3 HBA running 01.29.00.00 firmware, with SATA disks, and with smartd running, I'm seeing occasional task, bus, and host resets, some of which lead to hard faults of the HBA requiring a reboot. Abusively looping the smartctl command, # while true; do smartctl -a /dev/sdb > /dev/null; done dramatically increases the frequency of these failures to nearly one per minute. A high IO load through the HBA while looping smartctl seems to improve the chance of a full scsi host reset or a non-recoverable hang. I reduced what smartctl was doing down to a simple test case which causes the hang with a single IO when pointed at the sd interface. See the code at the bottom of this e-mail. It uses an SG_IO ioctl to issue a single pass-through ATA identify device command. If the buffer userspace gives for the read data has certain alignments, the task is issued to the HBA but the HBA fails to respond. If run against the sg interface, neither the test code nor smartctl causes a hang. sd and sg handle the SG_IO ioctl slightly differently. Unless you specifically set a flag to do direct IO, sg passes a buffer of its own, which is page-aligned, to the block layer and later copies the result into the userspace buffer regardless of its alignment. sd, on the other hand, always does direct IO unless the userspace buffer fails an alignment test at block/blk-map.c line 57, in which case a page-aligned buffer is created and used for the transfer. The alignment test currently checks for word-alignment, the default setup by scsi_lib.c; therefore, userspace buffers of almost any alignment are given directly to the HBA as DMA targets. The LSI 1068 hardware doesn't seem to like at least a couple of the alignments which cross a page boundary (see the test code below). Curiously, many page-boundary-crossing alignments do work just fine. So, either the hardware has an bug handling certain alignments or the hardware has a stricter alignment requirement than the driver is advertising. If stricter alignment is required, then in no case should misaligned buffers from userspace be allowed through without being bounced or at least causing an error to be returned. It seems the mptsas driver could use blk_queue_dma_alignment() to advertise a stricter alignment requirement. If it does, sd does the right thing and bounces misaligned buffers (see block/blk-map.c line 57). The following patch to 2.6.34-rc5 makes my symptoms go away. I'm sure this is the wrong place for this code, but it gets my idea across. Acked-by:
Kashyap Desai <Kashyap.Desai@lsi.com> Signed-off-by:
James Bottomley <James.Bottomley@suse.de> Signed-off-by:
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Eric Paris authored
commit 611da04f upstream. Since the .31 or so notify rewrite inotify has not sent events about inodes which are unmounted. This patch restores those events. Signed-off-by:
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