kernel/linux.git, branch v2.6.26.3

Linux 2.6.26.3

2008-08-20T18:11:37+00:00

crypto: padlock - fix VIA PadLock instruction usage with irq_ts_save/restore()

2008-08-20T18:05:15+00:00

crypto: padlock - fix VIA PadLock instruction usage with irq_ts_save/restore() [ Upstream commit: e49140120c88eb99db1a9172d9ac224c0f2bbdd2 ] Wolfgang Walter reported this oops on his via C3 using padlock for AES-encryption: ################################################################## BUG: unable to handle kernel NULL pointer dereference at 000001f0 IP: [] __switch_to+0x30/0x117 *pde = 00000000 Oops: 0002 [#1] PREEMPT Modules linked in: Pid: 2071, comm: sleep Not tainted (2.6.26 #11) EIP: 0060:[] EFLAGS: 00010002 CPU: 0 EIP is at __switch_to+0x30/0x117 EAX: 00000000 EBX: c0493300 ECX: dc48dd00 EDX: c0493300 ESI: dc48dd00 EDI: c0493530 EBP: c04cff8c ESP: c04cff7c DS: 007b ES: 007b FS: 0000 GS: 0033 SS: 0068 Process sleep (pid: 2071, ti=c04ce000 task=dc48dd00 task.ti=d2fe6000) Stack: dc48df30 c0493300 00000000 00000000 d2fe7f44 c03b5b43 c04cffc8 00000046 c0131856 0000005a dc472d3c c0493300 c0493470 d983ae00 00002696 00000000 c0239f54 00000000 c04c4000 c04cffd8 c01025fe c04f3740 00049800 c04cffe0 Call Trace: [] ? schedule+0x285/0x2ff [] ? pm_qos_requirement+0x3c/0x53 [] ? acpi_processor_idle+0x0/0x434 [] ? cpu_idle+0x73/0x7f [] ? rest_init+0x61/0x63 ======================= Wolfgang also found out that adding kernel_fpu_begin() and kernel_fpu_end() around the padlock instructions fix the oops. Suresh wrote: These padlock instructions though don't use/touch SSE registers, but it behaves similar to other SSE instructions. For example, it might cause DNA faults when cr0.ts is set. While this is a spurious DNA trap, it might cause oops with the recent fpu code changes. This is the code sequence that is probably causing this problem: a) new app is getting exec'd and it is somewhere in between start_thread() and flush_old_exec() in the load_xyz_binary() b) At pont "a", task's fpu state (like TS_USEDFPU, used_math() etc) is cleared. c) Now we get an interrupt/softirq which starts using these encrypt/decrypt routines in the network stack. This generates a math fault (as cr0.ts is '1') which sets TS_USEDFPU and restores the math that is in the task's xstate. d) Return to exec code path, which does start_thread() which does free_thread_xstate() and sets xstate pointer to NULL while the TS_USEDFPU is still set. e) At the next context switch from the new exec'd task to another task, we have a scenarios where TS_USEDFPU is set but xstate pointer is null. This can cause an oops during unlazy_fpu() in __switch_to() Now: 1) This should happen with or with out pre-emption. Viro also encountered similar problem with out CONFIG_PREEMPT. 2) kernel_fpu_begin() and kernel_fpu_end() will fix this problem, because kernel_fpu_begin() will manually do a clts() and won't run in to the situation of setting TS_USEDFPU in step "c" above. 3) This was working before the fpu changes, because its a spurious math fault which doesn't corrupt any fpu/sse registers and the task's math state was always in an allocated state. With out the recent lazy fpu allocation changes, while we don't see oops, there is a possible race still present in older kernels(for example, while kernel is using kernel_fpu_begin() in some optimized clear/copy page and an interrupt/softirq happens which uses these padlock instructions generating DNA fault). This is the failing scenario that existed even before the lazy fpu allocation changes: 0. CPU's TS flag is set 1. kernel using FPU in some optimized copy routine and while doing kernel_fpu_begin() takes an interrupt just before doing clts() 2. Takes an interrupt and ipsec uses padlock instruction. And we take a DNA fault as TS flag is still set. 3. We handle the DNA fault and set TS_USEDFPU and clear cr0.ts 4. We complete the padlock routine 5. Go back to step-1, which resumes clts() in kernel_fpu_begin(), finishes the optimized copy routine and does kernel_fpu_end(). At this point, we have cr0.ts again set to '1' but the task's TS_USEFPU is stilll set and not cleared. 6. Now kernel resumes its user operation. And at the next context switch, kernel sees it has do a FP save as TS_USEDFPU is still set and then will do a unlazy_fpu() in __switch_to(). unlazy_fpu() will take a DNA fault, as cr0.ts is '1' and now, because we are in __switch_to(), math_state_restore() will get confused and will restore the next task's FP state and will save it in prev tasks's FP state. Remember, in __switch_to() we are already on the stack of the next task but take a DNA fault for the prev task. This causes the fpu leakage. Fix the padlock instruction usage by calling them inside the context of new routines irq_ts_save/restore(), which clear/restore cr0.ts manually in the interrupt context. This will not generate spurious DNA in the context of the interrupt which will fix the oops encountered and the possible FPU leakage issue. Reported-and-bisected-by: Wolfgang Walter Signed-off-by: Suresh Siddha Signed-off-by: Herbert Xu Signed-off-by: Greg Kroah-Hartman

PCI: Limit VPD length for Broadcom 5708S

2008-08-20T18:05:14+00:00

commit 35405f256de924be56ea5edaca4cdc627f1bb0f8 upstream BCM5706S wont work correctly unless VPD length truncated to 128 Signed-off-by: Dean Hildebrand Signed-off-by: Jesse Barnes Signed-off-by: Greg Kroah-Hartman

CIFS: properly account for new user= field in SPNEGO upcall string allocation

2008-08-20T18:05:14+00:00

commit 66b8bd3c405389213de1d6ba6c2565990f62004f upstream [CIFS] properly account for new user= field in SPNEGO upcall string allocation ...it doesn't look like it's being accounted for at the moment. Also try to reorganize the calculation to make it a little more evident what each piece means. This should probably go to the stable series as well... Signed-off-by: Jeff Layton Signed-off-by: Steve French Signed-off-by: Greg Kroah-Hartman

usb-storage: automatically recognize bad residues

2008-08-20T18:05:14+00:00

commit 59f4ff2ecff4cef36378928cec891785b402e80c upstream This patch (as1119b) will help to reduce the clutter of usb-storage's unusual_devs file by automatically detecting some devices that need the IGNORE_RESIDUE flag. The idea is that devices should never return a non-zero residue for an INQUIRY or a READ CAPACITY command unless they failed to transfer all the requested data. So if one of these commands transfers a standard amount of data but there is a positive residue, we know that the residue is bogus and we can set the flag. This fixes the problems reported in Bugzilla #11125. Signed-off-by: Alan Stern Tested-by: Matthew Frost Signed-off-by: Greg Kroah-Hartman

usb-storage: revert DMA-alignment change for Wireless USB

2008-08-20T18:05:14+00:00

commit f756cbd458ab71c996a069cb3928fb1e2d7cd9cc upstream. This patch (as1110) reverts an earlier patch meant to help with Wireless USB host controllers. These controllers can have bulk maxpacket values larger than 512, which puts unusual constraints on the sizes of scatter-gather list elements. However it turns out that the block layer does not provide the support we need to enforce these constraints; merely changing the DMA alignment mask doesn't help. Hence there's no reason to keep the original patch. The Wireless USB problem will have to be solved a different way. In addition, there is a reason to get rid of the earlier patch. By dereferencing a pointer stored in the ep_in array of struct usb_device, the current code risks an invalid memory access when it runs concurrently with device removal. The members of that array are cleared before the driver's disconnect method is called, so it should not try to use them. Signed-off-by: Alan Stern Signed-off-by: Greg Kroah-Hartman

qla2xxx: Set an rport's dev_loss_tmo value in a consistent manner.

2008-08-20T18:05:13+00:00

[ Upstream commit 85821c906cf3563a00a3d98fa380a2581a7a5ff1 ] As there's no point in adding a fixed-fudge value (originally 5 seconds), honor the user settings only. We also remove the driver's dead-callback get_rport_dev_loss_tmo function (qla2x00_get_rport_loss_tmo()). Signed-off-by: Andrew Vasquez Signed-off-by: James Bottomley Signed-off-by: Greg Kroah-Hartman

qla2xxx: Add dev_loss_tmo_callbk/terminate_rport_io callback support.

2008-08-20T18:05:13+00:00

[ Upstream commit 5f3a9a207f1fccde476dd31b4c63ead2967d934f ] Signed-off-by: Seokmann Ju Signed-off-by: Andrew Vasquez Signed-off-by: James Bottomley Signed-off-by: Greg Kroah-Hartman

x86: fix setup code crashes on my old 486 box

2008-08-20T18:05:13+00:00

commit 7b27718bdb1b70166383dec91391df5534d449ee upstream yesterday I tried to reactivate my old 486 box and wanted to install a current Linux with latest kernel on it. But it turned out that the latest kernel does not boot because the machine crashes early in the setup code. After some debugging it turned out that the problem is the query_ist() function. If this interrupt with that function is called the machine simply locks up. It looks like a BIOS bug. Looking for a workaround for this problem I wrote the attached patch. It checks for the CPUID instruction and if it is not implemented it does not call the speedstep BIOS function. As far as I know speedstep should be available since some Pentium earliest. Alan Cox observed that it's available since the Pentium II, so cpuid levels 4 and 5 can be excluded altogether. H. Peter Anvin cleaned up the code some more: > Right in concept, but I dislike the implementation (duplication of the > CPU detect code we already have). Could you try this patch and see if > it works for you? which, with a small modification to fix a build error with it the resulting kernel boots on my machine. Signed-off-by: Joerg Roedel Signed-off-by: "H. Peter Anvin" Signed-off-by: Ingo Molnar Signed-off-by: Greg Kroah-Hartman

x86: fix spin_is_contended()

2008-08-20T18:05:13+00:00

commit 7bc069c6bc4ede519a7116be1b9e149a1dbf787a upstream The masked difference is what needs to be compared against 1, rather than the difference of masked values (which can be negative). Signed-off-by: Jan Beulich Acked-by: Nick Piggin Signed-off-by: Ingo Molnar Signed-off-by: Greg Kroah-Hartman