user/sven/linux.git/Documentation, branch v3.9.11

powerpc/tm: Abort on emulation and alignment faults

2013-06-07T19:53:20Z

commit 6ce6c629fd8254b3177650de99699682ff7f6707 upstream. If we are emulating an instruction inside an active user transaction that touches memory, the kernel can't emulate it as it operates in transactional suspend context. We need to abort these transactions and send them back to userspace for the hardware to rollback. We can service these if the user transaction is in suspend mode, since the kernel will operate in the same suspend context. This adds a check to all alignment faults and to specific instruction emulations (only string instructions for now). If the user process is in an active (non-suspended) transaction, we abort the transaction go back to userspace allowing the HW to roll back the transaction and tell the user of the failure. This also adds new tm abort cause codes to report the reason of the persistent error to the user. Crappy test case here http://neuling.org/devel/junkcode/aligntm.c Signed-off-by: Michael Neuling Signed-off-by: Benjamin Herrenschmidt Signed-off-by: Greg Kroah-Hartman

powerpc/tm: Fix userspace stack corruption on signal delivery for active transactions

2013-06-07T19:53:19Z

commit 2b3f8e87cf99a33fb6faf5026d7147748bbd77b6 upstream. When in an active transaction that takes a signal, we need to be careful with the stack. It's possible that the stack has moved back up after the tbegin. The obvious case here is when the tbegin is called inside a function that returns before a tend. In this case, the stack is part of the checkpointed transactional memory state. If we write over this non transactionally or in suspend, we are in trouble because if we get a tm abort, the program counter and stack pointer will be back at the tbegin but our in memory stack won't be valid anymore. To avoid this, when taking a signal in an active transaction, we need to use the stack pointer from the checkpointed state, rather than the speculated state. This ensures that the signal context (written tm suspended) will be written below the stack required for the rollback. The transaction is aborted becuase of the treclaim, so any memory written between the tbegin and the signal will be rolled back anyway. For signals taken in non-TM or suspended mode, we use the normal/non-checkpointed stack pointer. Tested with 64 and 32 bit signals Signed-off-by: Michael Neuling Signed-off-by: Benjamin Herrenschmidt Signed-off-by: Greg Kroah-Hartman

powerpc/tm: Update cause codes documentation

2013-06-07T19:53:19Z

commit 24b92375dc4ec8a15262e8aaaab60b7404d4b1e7 upstream. Signed-off-by: Michael Neuling Signed-off-by: Benjamin Herrenschmidt Signed-off-by: Greg Kroah-Hartman

Merge branch 'x86-kdump-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2013-04-21T01:40:36Z

Pull kdump fixes from Peter Anvin: "The kexec/kdump people have found several problems with the support for loading over 4 GiB that was introduced in this merge cycle. This is partly due to a number of design problems inherent in the way the various pieces of kdump fit together (it is pretty horrifically manual in many places.) After a *lot* of iterations this is the patchset that was agreed upon, but of course it is now very late in the cycle. However, because it changes both the syntax and semantics of the crashkernel option, it would be desirable to avoid a stable release with the broken interfaces." I'm not happy with the timing, since originally the plan was to release the final 3.9 tomorrow. But apparently I'm doing an -rc8 instead... * 'x86-kdump-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: kexec: use Crash kernel for Crash kernel low x86, kdump: Change crashkernel_high/low= to crashkernel=,high/low x86, kdump: Retore crashkernel= to allocate under 896M x86, kdump: Set crashkernel_low automatically

Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2013-04-21T01:38:48Z

Pull x86 fixes from Peter Anvin: "Three groups of fixes: 1. Make sure we don't execute the early microcode patching if family < 6, since it would touch MSRs which don't exist on those families, causing crashes. 2. The Xen partial emulation of HyperV can be dealt with more gracefully than just disabling the driver. 3. More EFI variable space magic. In particular, variables hidden from runtime code need to be taken into account too." * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86, microcode: Verify the family before dispatching microcode patching x86, hyperv: Handle Xen emulation of Hyper-V more gracefully x86,efi: Implement efi_no_storage_paranoia parameter efi: Export efi_query_variable_store() for efivars.ko x86/Kconfig: Make EFI select UCS2_STRING efi: Distinguish between "remaining space" and actually used space efi: Pass boot services variable info to runtime code Move utf16 functions to kernel core and rename x86,efi: Check max_size only if it is non-zero. x86, efivars: firmware bug workarounds should be in platform code

Merge remote-tracking branch 'efi/urgent' into x86/urgent

2013-04-20T00:09:03Z

Matt Fleming (1): x86, efivars: firmware bug workarounds should be in platform code Matthew Garrett (3): Move utf16 functions to kernel core and rename efi: Pass boot services variable info to runtime code efi: Distinguish between "remaining space" and actually used space Richard Weinberger (2): x86,efi: Check max_size only if it is non-zero. x86,efi: Implement efi_no_storage_paranoia parameter Sergey Vlasov (2): x86/Kconfig: Make EFI select UCS2_STRING efi: Export efi_query_variable_store() for efivars.ko Signed-off-by: H. Peter Anvin

x86, kdump: Change crashkernel_high/low= to crashkernel=,high/low

2013-04-17T19:35:33Z

Per hpa, use crashkernel=X,high crashkernel=Y,low instead of crashkernel_hign=X crashkernel_low=Y. As that could be extensible. -v2: according to Vivek, change delimiter to ; -v3: let hign and low only handle simple form and it conforms to description in kernel-parameters.txt still keep crashkernel=X override any crashkernel=X,high crashkernel=Y,low -v4: update get_last_crashkernel returning and add more strict checking in parse_crashkernel_simple() found by HATAYAMA. -v5: Change delimiter back to , according to HPA. also separate parse_suffix from parse_simper according to vivek. so we can avoid @pos in that path. -v6: Tight the checking about crashkernel=X,highblahblah,high found by HTYAYAMA. Cc: HATAYAMA Daisuke Signed-off-by: Yinghai Lu Link: http://lkml.kernel.org/r/1366089828-19692-5-git-send-email-yinghai@kernel.org Acked-by: Vivek Goyal Signed-off-by: H. Peter Anvin

x86, kdump: Retore crashkernel= to allocate under 896M

2013-04-17T19:35:33Z

Vivek found old kexec-tools does not work new kernel anymore. So change back crashkernel= back to old behavoir, and add crashkernel_high= to let user decide if buffer could be above 4G, and also new kexec-tools will be needed. -v2: let crashkernel=X override crashkernel_high= update description about _high will be ignored by crashkernel=X -v3: update description about kernel-parameters.txt according to Vivek. Signed-off-by: Yinghai Lu Link: http://lkml.kernel.org/r/1366089828-19692-4-git-send-email-yinghai@kernel.org Acked-by: Vivek Goyal Signed-off-by: H. Peter Anvin

x86, kdump: Set crashkernel_low automatically

2013-04-17T19:35:32Z

Chao said that kdump does does work well on his system on 3.8 without extra parameter, even iommu does not work with kdump. And now have to append crashkernel_low=Y in first kernel to make kdump work. We have now modified crashkernel=X to allocate memory beyong 4G (if available) and do not allocate low range for crashkernel if the user does not specify that with crashkernel_low=Y. This causes regression if iommu is not enabled. Without iommu, swiotlb needs to be setup in first 4G and there is no low memory available to second kernel. Set crashkernel_low automatically if the user does not specify that. For system that does support IOMMU with kdump properly, user could specify crashkernel_low=0 to save that 72M low ram. -v3: add swiotlb_size() according to Konrad. -v4: add comments what 8M is for according to hpa. also update more crashkernel_low= in kernel-parameters.txt -v5: update changelog according to Vivek. -v6: Change description about swiotlb referring according to HATAYAMA. Reported-by: WANG Chao Tested-by: WANG Chao Signed-off-by: Yinghai Lu Link: http://lkml.kernel.org/r/1366089828-19692-2-git-send-email-yinghai@kernel.org Acked-by: Vivek Goyal Signed-off-by: H. Peter Anvin

x86,efi: Implement efi_no_storage_paranoia parameter

2013-04-17T14:13:38Z

Using this parameter one can disable the storage_size/2 check if he is really sure that the UEFI does sane gc and fulfills the spec. This parameter is useful if a devices uses more than 50% of the storage by default. The Intel DQSW67 desktop board is such a sucker for exmaple. Signed-off-by: Richard Weinberger Signed-off-by: Matt Fleming