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2014-10-31KVM: s390: unintended fallthrough for external callChristian Borntraeger
commit f346026e55f1efd3949a67ddd1dcea7c1b9a615e upstream. We must not fallthrough if the conditions for external call are not met. Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Reviewed-by: Thomas Huth <thuth@linux.vnet.ibm.com> Signed-off-by: Jiri Slaby <jslaby@suse.cz>
2014-10-31kvm: fix potentially corrupt mmio cacheDavid Matlack
commit ee3d1570b58677885b4552bce8217fda7b226a68 upstream. vcpu exits and memslot mutations can run concurrently as long as the vcpu does not aquire the slots mutex. Thus it is theoretically possible for memslots to change underneath a vcpu that is handling an exit. If we increment the memslot generation number again after synchronize_srcu_expedited(), vcpus can safely cache memslot generation without maintaining a single rcu_dereference through an entire vm exit. And much of the x86/kvm code does not maintain a single rcu_dereference of the current memslots during each exit. We can prevent the following case: vcpu (CPU 0) | thread (CPU 1) --------------------------------------------+-------------------------- 1 vm exit | 2 srcu_read_unlock(&kvm->srcu) | 3 decide to cache something based on | old memslots | 4 | change memslots | (increments generation) 5 | synchronize_srcu(&kvm->srcu); 6 retrieve generation # from new memslots | 7 tag cache with new memslot generation | 8 srcu_read_unlock(&kvm->srcu) | ... | <action based on cache occurs even | though the caching decision was based | on the old memslots> | ... | <action *continues* to occur until next | memslot generation change, which may | be never> | | By incrementing the generation after synchronizing with kvm->srcu readers, we ensure that the generation retrieved in (6) will become invalid soon after (8). Keeping the existing increment is not strictly necessary, but we do keep it and just move it for consistency from update_memslots to install_new_memslots. It invalidates old cached MMIOs immediately, instead of having to wait for the end of synchronize_srcu_expedited, which makes the code more clearly correct in case CPU 1 is preempted right after synchronize_srcu() returns. To avoid halving the generation space in SPTEs, always presume that the low bit of the generation is zero when reconstructing a generation number out of an SPTE. This effectively disables MMIO caching in SPTEs during the call to synchronize_srcu_expedited. Using the low bit this way is somewhat like a seqcount---where the protected thing is a cache, and instead of retrying we can simply punt if we observe the low bit to be 1. Signed-off-by: David Matlack <dmatlack@google.com> Reviewed-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com> Reviewed-by: David Matlack <dmatlack@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Jiri Slaby <jslaby@suse.cz>
2014-10-31kvm: x86: fix stale mmio cache bugDavid Matlack
commit 56f17dd3fbc44adcdbc3340fe3988ddb833a47a7 upstream. The following events can lead to an incorrect KVM_EXIT_MMIO bubbling up to userspace: (1) Guest accesses gpa X without a memory slot. The gfn is cached in struct kvm_vcpu_arch (mmio_gfn). On Intel EPT-enabled hosts, KVM sets the SPTE write-execute-noread so that future accesses cause EPT_MISCONFIGs. (2) Host userspace creates a memory slot via KVM_SET_USER_MEMORY_REGION covering the page just accessed. (3) Guest attempts to read or write to gpa X again. On Intel, this generates an EPT_MISCONFIG. The memory slot generation number that was incremented in (2) would normally take care of this but we fast path mmio faults through quickly_check_mmio_pf(), which only checks the per-vcpu mmio cache. Since we hit the cache, KVM passes a KVM_EXIT_MMIO up to userspace. This patch fixes the issue by using the memslot generation number to validate the mmio cache. Signed-off-by: David Matlack <dmatlack@google.com> [xiaoguangrong: adjust the code to make it simpler for stable-tree fix.] Signed-off-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com> Reviewed-by: David Matlack <dmatlack@google.com> Reviewed-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com> Tested-by: David Matlack <dmatlack@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Jiri Slaby <jslaby@suse.cz>
2014-10-31sparc64: Kill unnecessary tables and increase MAX_BANKS.David S. Miller
[ Upstream commit d195b71bad4347d2df51072a537f922546a904f1 ] swapper_low_pmd_dir and swapper_pud_dir are actually completely useless and unnecessary. We just need swapper_pg_dir[]. Naturally the other page table chunks will be allocated on an as-needed basis. Since the kernel actually accesses these tables in the PAGE_OFFSET view, there is not even a TLB locality advantage of placing them in the kernel image. Use the hard coded vmlinux.ld.S slot for swapper_pg_dir which is naturally page aligned. Increase MAX_BANKS to 1024 in order to handle heavily fragmented virtual guests. Even with this MAX_BANKS increase, the kernel is 20K+ smaller. Signed-off-by: David S. Miller <davem@davemloft.net> Acked-by: Bob Picco <bob.picco@oracle.com>
2014-10-31sparc64: sparse irqbob picco
[ Upstream commit ee6a9333fa58e11577c1b531b8e0f5ffc0fd6f50 ] This patch attempts to do a few things. The highlights are: 1) enable SPARSE_IRQ unconditionally, 2) kills off !SPARSE_IRQ code 3) allocates ivector_table at boot time and 4) default to cookie only VIRQ mechanism for supported firmware. The first firmware with cookie only support for me appears on T5. You can optionally force the HV firmware to not cookie only mode which is the sysino support. The sysino is a deprecated HV mechanism according to the most recent SPARC Virtual Machine Specification. HV_GRP_INTR is what controls the cookie/sysino firmware versioning. The history of this interface is: 1) Major version 1.0 only supported sysino based interrupt interfaces. 2) Major version 2.0 added cookie based VIRQs, however due to the fact that OSs were using the VIRQs without negoatiating major version 2.0 (Linux and Solaris are both guilty), the VIRQs calls were allowed even with major version 1.0 To complicate things even further, the VIRQ interfaces were only actually hooked up in the hypervisor for LDC interrupt sources. VIRQ calls on other device types would result in HV_EINVAL errors. So effectively, major version 2.0 is unusable. 3) Major version 3.0 was created to signal use of VIRQs and the fact that the hypervisor has these calls hooked up for all interrupt sources, not just those for LDC devices. A new boot option is provided should cookie only HV support have issues. hvirq - this is the version for HV_GRP_INTR. This is related to HV API versioning. The code attempts major=3 first by default. The option can be used to override this default. I've tested with SPARSE_IRQ on T5-8, M7-4 and T4-X and Jalap?no. Signed-off-by: Bob Picco <bob.picco@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-31sparc64: Adjust vmalloc region size based upon available virtual address bits.David S. Miller
[ Upstream commit bb4e6e85daa52a9f6210fa06a5ec6269598a202b ] In order to accomodate embedded per-cpu allocation with large numbers of cpus and numa nodes, we have to use as much virtual address space as possible for the vmalloc region. Otherwise we can get things like: PERCPU: max_distance=0x380001c10000 too large for vmalloc space 0xff00000000 So, once we select a value for PAGE_OFFSET, derive the size of the vmalloc region based upon that. Signed-off-by: David S. Miller <davem@davemloft.net> Acked-by: Bob Picco <bob.picco@oracle.com>
2014-10-31sparc64: Increase MAX_PHYS_ADDRESS_BITS to 53.David S. Miller
commit 7c0fa0f24bb76ce3d67be7f737b799846a04570f upstream. Make sure, at compile time, that the kernel can properly support whatever MAX_PHYS_ADDRESS_BITS is defined to. On M7 chips, use a max_phys_bits value of 49. Based upon a patch by Bob Picco. Signed-off-by: David S. Miller <davem@davemloft.net> Acked-by: Bob Picco <bob.picco@oracle.com>
2014-10-31sparc64: Use kernel page tables for vmemmap.David S. Miller
[ Upstream commit c06240c7f5c39c83dfd7849c0770775562441b96 ] For sparse memory configurations, the vmemmap array behaves terribly and it takes up an inordinate amount of space in the BSS section of the kernel image unconditionally. Just build huge PMDs and look them up just like we do for TLB misses in the vmalloc area. Kernel BSS shrinks by about 2MB. Signed-off-by: David S. Miller <davem@davemloft.net> Acked-by: Bob Picco <bob.picco@oracle.com>
2014-10-31sparc64: Fix physical memory management regressions with large max_phys_bits.David S. Miller
[ Upstream commit 0dd5b7b09e13dae32869371e08e1048349fd040c ] If max_phys_bits needs to be > 43 (f.e. for T4 chips), things like DEBUG_PAGEALLOC stop working because the 3-level page tables only can cover up to 43 bits. Another problem is that when we increased MAX_PHYS_ADDRESS_BITS up to 47, several statically allocated tables became enormous. Compounding this is that we will need to support up to 49 bits of physical addressing for M7 chips. The two tables in question are sparc64_valid_addr_bitmap and kpte_linear_bitmap. The first holds a bitmap, with 1 bit for each 4MB chunk of physical memory, indicating whether that chunk actually exists in the machine and is valid. The second table is a set of 2-bit values which tell how large of a mapping (4MB, 256MB, 2GB, 16GB, respectively) we can use at each 256MB chunk of ram in the system. These tables are huge and take up an enormous amount of the BSS section of the sparc64 kernel image. Specifically, the sparc64_valid_addr_bitmap is 4MB, and the kpte_linear_bitmap is 128K. So let's solve the space wastage and the DEBUG_PAGEALLOC problem at the same time, by using the kernel page tables (as designed) to manage this information. We have to keep using large mappings when DEBUG_PAGEALLOC is disabled, and we do this by encoding huge PMDs and PUDs. On a T4-2 with 256GB of ram the kernel page table takes up 16K with DEBUG_PAGEALLOC disabled and 256MB with it enabled. Furthermore, this memory is dynamically allocated at run time rather than coded statically into the kernel image. Signed-off-by: David S. Miller <davem@davemloft.net> Acked-by: Bob Picco <bob.picco@oracle.com>
2014-10-31sparc64: Adjust KTSB assembler to support larger physical addresses.David S. Miller
[ Upstream commit 8c82dc0e883821c098c8b0b130ffebabf9aab5df ] As currently coded the KTSB accesses in the kernel only support up to 47 bits of physical addressing. Adjust the instruction and patching sequence in order to support arbitrary 64 bits addresses. Signed-off-by: David S. Miller <davem@davemloft.net> Acked-by: Bob Picco <bob.picco@oracle.com>
2014-10-31sparc64: Define VA hole at run time, rather than at compile time.David S. Miller
[ Upstream commit 4397bed080598001e88f612deb8b080bb1cc2322 ] Now that we use 4-level page tables, we can provide up to 53-bits of virtual address space to the user. Adjust the VA hole based upon the capabilities of the cpu type probed. Signed-off-by: David S. Miller <davem@davemloft.net> Acked-by: Bob Picco <bob.picco@oracle.com>
2014-10-31sparc64: Switch to 4-level page tables.David S. Miller
[ Upstream commit ac55c768143aa34cc3789c4820cbb0809a76fd9c ] This has become necessary with chips that support more than 43-bits of physical addressing. Based almost entirely upon a patch by Bob Picco. Signed-off-by: David S. Miller <davem@davemloft.net> Acked-by: Bob Picco <bob.picco@oracle.com>
2014-10-31sparc64: T5 PMUbob picco
commit 05aa1651e8b9ca078b1808a2fe7b50703353ec02 upstream. The T5 (niagara5) has different PCR related HV fast trap values and a new HV API Group. This patch utilizes these and shares when possible with niagara4. We use the same sparc_pmu niagara4_pmu. Should there be new effort to obtain the MCU perf statistics then this would have to be changed. Cc: sparclinux@vger.kernel.org Signed-off-by: Bob Picco <bob.picco@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-31sparc64: cpu hardware caps support for sparc M6 and M7Allen Pais
commit 408316258521168614bfb4da0e070490d3e65a17 upstream. Signed-off-by: Allen Pais <allen.pais@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-31sparc64: support M6 and M7 for building CPU distribution mapAllen Pais
commit 9bd3ee33f6b97de092610d8dcabc4cb98d99505c upstream. Add M6 and M7 chip type in cpumap.c to correctly build CPU distribution map that spans all online CPUs. Signed-off-by: Allen Pais <allen.pais@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-31sparc64: correctly recognise M6 and M7 cpu typeAllen Pais
commit cadbb58039f7cab1def9c931012ab04c953a6997 upstream. The following patch adds support for correctly recognising M6 and M7 cpu type. Signed-off-by: Allen Pais <allen.pais@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-31sparc64: Fix hibernation code refrence to PAGE_OFFSET.David S. Miller
commit 9d0713edf72461438bc3526e4ea55fec47754cd9 upstream. We changed PAGE_OFFSET to be a variable rather than a constant, but this reference here in the hibernate assembler got missed. Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-31sparc64: Add basic validations to {pud,pmd}_bad().David S. Miller
[ Upstream commit 26cf432551d749e7d581db33529507a711c6eaab ] Instead of returning false we should at least check the most basic things, otherwise page table corruptions will be very difficult to debug. PMD and PTE tables are of size PAGE_SIZE, so none of the sub-PAGE_SIZE bits should be set. We also complement this with a check that the physical address the pud/pmd points to is valid memory. PowerPC was used as a guide while implementating this. Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-10-31sparc64: Use 'ILOG2_4MB' instead of constant '22'.David S. Miller
[ Upstream commit 0eef331a3d0ee970dcbebd1bd5fcb57ca33ece01 ] Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-10-31sparc64: Fix range check in kern_addr_valid().David S. Miller
[ Upstream commit ee73887e92a69ae0a5cda21c68ea75a27804c944 ] In commit b2d438348024b75a1ee8b66b85d77f569a5dfed8 ("sparc64: Make PAGE_OFFSET variable."), the MAX_PHYS_ADDRESS_BITS value was increased (to 47). This constant reference to '41UL' was missed. Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-10-31sparc64: Don't use _PAGE_PRESENT in pte_modify() mask.David S. Miller
[ Upstream commit eaf85da82669b057f20c4e438dc2566b51a83af6 ] Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-10-31sparc64: Fix hex values in comment above pte_modify().David S. Miller
[ Upstream commit c2e4e676adb40ea764af79d3e08be954e14a0f4c ] When _PAGE_SPECIAL and _PAGE_PMD_HUGE were added to the mask, the comment was not updated. Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-10-31sparc64: Fix bugs in get_user_pages_fast() wrt. THP.David S. Miller
[ Upstream commit 04df419de34104d8818b8c5cffaa062fa36d20ea ] The large PMD path needs to check _PAGE_VALID not _PAGE_PRESENT, to decide if it needs to bail and return 0. pmd_large() should therefore just check _PAGE_PMD_HUGE. Calls to gup_huge_pmd() are guarded with a check of pmd_large(), so we just need to add a valid bit check. Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-10-31sparc64: Fix huge PMD invalidation.David S. Miller
[ Upstream commit 51e5ef1bb7ab0e5fa7de4e802da5ab22fe35f0bf ] On sparc64 "present" and "valid" are seperate PTE bits, this allows us to naturally distinguish between the user explicitly asking for PROT_NONE with mprotect() and other situations. However we weren't handling this properly in the huge PMD paths. First of all, the page table walker in the TSB miss path only checks for _PAGE_PMD_HUGE. So the generic pmdp_invalidate() would clear _PAGE_PRESENT but the TLB miss paths would still load it into the TLB as a valid huge PMD. Fix this by clearing the valid bit in pmdp_invalidate(), and also checking the valid bit in USER_PGTABLE_CHECK_PMD_HUGE using "brgez" since _PAGE_VALID is bit 63 in both the sun4u and sun4v pte layouts. Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-10-31sparc64: Fix executable bit testing in set_pmd_at() paths.David S. Miller
[ Upstream commit 5b1e94fa439a3227beefad58c28c17f68287a8e9 ] This code was mistakenly using the exec bit from the PMD in all cases, even when the PMD isn't a huge PMD. If it's not a huge PMD, test the exec bit in the individual ptes down in tlb_batch_pmd_scan(). Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-10-31Revert "sparc64: Fix __copy_{to,from}_user_inatomic defines."Dave Kleikamp
This reverts commit 145e1c0023585e0e8f6df22316308ec61c5066b2. This commit broke the behavior of __copy_from_user_inatomic when it is only partially successful. Instead of returning the number of bytes not copied, it now returns 1. This translates to the wrong value being returned by iov_iter_copy_from_user_atomic. xfstests generic/246 and LTP writev01 both fail on btrfs and nfs because of this. Signed-off-by: Dave Kleikamp <dave.kleikamp@oracle.com> Cc: Hugh Dickins <hughd@google.com> Cc: David S. Miller <davem@davemloft.net> Cc: sparclinux@vger.kernel.org Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-31sparc: PCI: Fix incorrect address calculation of PCI Bridge windows on ↵oftedal
Simba-bridges commit 557fc5873ef178c4b3e1e36a42db547ecdc43f9b upstream. The SIMBA APB Bridges lacks the 'ranges' of-property describing the PCI I/O and memory areas located beneath the bridge. Faking this information has been performed by reading range registers in the APB bridge, and calculating the corresponding areas. In commit 01f94c4a6ced476ce69b895426fc29bfc48c69bd ("Fix sabre pci controllers with new probing scheme.") a bug was introduced into this calculation, causing the PCI memory areas to be calculated incorrectly: The shift size was set to be identical for I/O and MEM ranges, which is incorrect. This patch set the shift size of the MEM range back to the value used before 01f94c4a6ced476ce69b895426fc29bfc48c69bd. Signed-off-by: Kjetil Oftedal <oftedal@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-31sparc64: Encode huge PMDs using PTE encoding.David S. Miller
commit a7b9403f0e6d5f99139dca18be885819c8d380a1 upstream. Now that we have 64-bits for PMDs we can stop using special encodings for the huge PMD values, and just put real PTEs in there. We allocate a _PAGE_PMD_HUGE bit to distinguish between plain PMDs and huge ones. It is the same for both 4U and 4V PTE layouts. We also use _PAGE_SPECIAL to indicate the splitting state, since a huge PMD cannot also be special. All of the PMD --> PTE translation code disappears, and most of the huge PMD bit modifications and tests just degenerate into the PTE operations. In particular USER_PGTABLE_CHECK_PMD_HUGE becomes trivial. As a side effect, normal PMDs don't shift the physical address around. This also speeds up the page table walks in the TLB miss paths since they don't have to do the shifts any more. Another non-trivial aspect is that pte_modify() has to be changed to preserve the _PAGE_PMD_HUGE bits as well as the page size field of the pte. Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-31sparc64: Move to 64-bit PGDs and PMDs.David S. Miller
commit 2b77933c28f5044629bb19e8045aae65b72b939d upstream. To make the page tables compact, we were using 32-bit PGDs and PMDs. We only had to support <= 43 bits of physical addresses so this was quite feasible. In order to support larger physical addresses we have to move to 64-bit PGDs and PMDs. Most of the changes are straight-forward: 1) {pgd,pmd}_t --> unsigned long 2) Anything that tries to use plain "unsigned int" types with pgd/pmd values needs to be adjusted. In particular things like "0U" become "0UL". 3) {PGDIR,PMD}_BITS decrease by one. 4) In the assembler page table walkers, use "ldxa" instead of "lduwa" and adjust the low bit masks to clear out the low 3 bits instead of just the low 2 bits during pgd/pmd address formation. Also, use PTRS_PER_PGD and PTRS_PER_PMD in the sizing of the swapper_{pg_dir,low_pmd_dir} arrays. This patch does not try to take advantage of having 64-bits in the PMDs to simplify the hugepage code, that will come in a subsequent change. Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-31sparc64: Move from 4MB to 8MB huge pages.David S. Miller
commit 37b3a8ff3e086cd5c369e77d2383b691b2874cd6 upstream. The impetus for this is that we would like to move to 64-bit PMDs and PGDs, but that would result in only supporting a 42-bit address space with the current page table layout. It'd be nice to support at least 43-bits. The reason we'd end up with only 42-bits after making PMDs and PGDs 64-bit is that we only use half-page sized PTE tables in order to make PMDs line up to 4MB, the hardware huge page size we use. So what we do here is we make huge pages 8MB, and fabricate them using 4MB hw TLB entries. Facilitate this by providing a "REAL_HPAGE_SHIFT" which is used in places that really need to operate on hardware 4MB pages. Use full pages (512 entries) for PTE tables, and adjust PMD_SHIFT, PGD_SHIFT, and the build time CPP test as needed. Use a CPP test to make sure REAL_HPAGE_SHIFT and the _PAGE_SZHUGE_* we use match up. This makes the pgtable cache completely unused, so remove the code managing it and the state used in mm_context_t. Now we have less spinlocks taken in the page table allocation path. The technique we use to fabricate the 8MB pages is to transfer bit 22 from the missing virtual address into the PTEs physical address field. That takes care of the transparent huge pages case. For hugetlb, we fill things in at the PTE level and that code already puts the sub huge page physical bits into the PTEs, based upon the offset, so there is nothing special we need to do. It all just works out. So, a small amount of complexity in the THP case, but this code is about to get much simpler when we move the 64-bit PMDs as we can move away from the fancy 32-bit huge PMD encoding and just put a real PTE value in there. With bug fixes and help from Bob Picco. Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-31sparc64: Make PAGE_OFFSET variable.David S. Miller
commit b2d438348024b75a1ee8b66b85d77f569a5dfed8 upstream. Choose PAGE_OFFSET dynamically based upon cpu type. Original UltraSPARC-I (spitfire) chips only supported a 44-bit virtual address space. Newer chips (T4 and later) support 52-bit virtual addresses and up to 47-bits of physical memory space. Therefore we have to adjust PAGE_SIZE dynamically based upon the capabilities of the chip. Note that this change alone does not allow us to support > 43-bit physical memory, to do that we need to re-arrange our page table support. The current encodings of the pmd_t and pgd_t pointers restricts us to "32 + 11" == 43 bits. This change can waste quite a bit of memory for the various tables. In particular, a future change should work to size and allocate kern_linear_bitmap[] and sparc64_valid_addr_bitmap[] dynamically. This isn't easy as we really cannot take a TLB miss when accessing kern_linear_bitmap[]. We'd have to lock it into the TLB or similar. Signed-off-by: David S. Miller <davem@davemloft.net> Acked-by: Bob Picco <bob.picco@oracle.com>
2014-10-31sparc64: Fix inconsistent max-physical-address defines.David S. Miller
commit f998c9c0d663b013e3aa3ba78908396c8c497218 upstream. Some parts of the code use '41' others use '42', make them all use the same value. Signed-off-by: David S. Miller <davem@davemloft.net> Acked-by: Bob Picco <bob.picco@oracle.com>
2014-10-31sparc64: Document the shift counts used to validate linear kernel addresses.David S. Miller
commit bb7b435388b9f035ecfb16f42b5c6bf428359c63 upstream. This way we can see exactly what they are derived from, and in particular how they would change if we were to use a different PAGE_OFFSET value. Signed-off-by: David S. Miller <davem@davemloft.net> Acked-by: Bob Picco <bob.picco@oracle.com>
2014-10-31sparc64: Define PAGE_OFFSET in terms of physical address bits.David S. Miller
commit e0a45e3580a033669b24b04c3535515d69bb9702 upstream. This makes clearer the implications for a given choosen value. Based upon patches by Bob Picco. Signed-off-by: David S. Miller <davem@davemloft.net> Acked-by: Bob Picco <bob.picco@oracle.com>
2014-10-31sparc64: Use PAGE_OFFSET instead of a magic constant.David S. Miller
commit 922631b988d8cbb821ebe2c67feffc0b95264894 upstream. This pertains to all of the computations of the kernel fast TLB miss xor values. Based upon a patch by Bob Picco. Signed-off-by: David S. Miller <davem@davemloft.net> Acked-by: Bob Picco <bob.picco@oracle.com>
2014-10-31sparc64: Clean up 64-bit mmap exclusion defines.David S. Miller
commit c920745e6964bd4b9315a17b018d83fad66010d3 upstream. Older UltraSPARC chips had an address space hole due to the MMU only supporting 44-bit virtual addresses. The top end of this hole also has the same value as the current definition of PAGE_OFFSET, so this can be confusing. Consolidate the defines for the userspace mmap exclusion range into page_64.h and use them in sys_sparc_64.c and hugetlbpage.c Signed-off-by: David S. Miller <davem@davemloft.net> Acked-by: Bob Picco <bob.picco@oracle.com>
2014-10-31sparc64: Implement __get_user_pages_fast().David S. Miller
[ Upstream commit 06090e8ed89ea2113a236befb41f71d51f100e60 ] It is not sufficient to only implement get_user_pages_fast(), you must also implement the atomic version __get_user_pages_fast() otherwise you end up using the weak symbol fallback implementation which simply returns zero. This is dangerous, because it causes the futex code to loop forever if transparent hugepages are supported (see get_futex_key()). Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-31sparc64: Fix register corruption in top-most kernel stack frame during boot.David S. Miller
[ Upstream commit ef3e035c3a9b81da8a778bc333d10637acf6c199 ] Meelis Roos reported that kernels built with gcc-4.9 do not boot, we eventually narrowed this down to only impacting machines using UltraSPARC-III and derivitive cpus. The crash happens right when the first user process is spawned: [ 54.451346] Kernel panic - not syncing: Attempted to kill init! exitcode=0x00000004 [ 54.451346] [ 54.571516] CPU: 1 PID: 1 Comm: init Not tainted 3.16.0-rc2-00211-gd7933ab #96 [ 54.666431] Call Trace: [ 54.698453] [0000000000762f8c] panic+0xb0/0x224 [ 54.759071] [000000000045cf68] do_exit+0x948/0x960 [ 54.823123] [000000000042cbc0] fault_in_user_windows+0xe0/0x100 [ 54.902036] [0000000000404ad0] __handle_user_windows+0x0/0x10 [ 54.978662] Press Stop-A (L1-A) to return to the boot prom [ 55.050713] ---[ end Kernel panic - not syncing: Attempted to kill init! exitcode=0x00000004 Further investigation showed that compiling only per_cpu_patch() with an older compiler fixes the boot. Detailed analysis showed that the function is not being miscompiled by gcc-4.9, but it is using a different register allocation ordering. With the gcc-4.9 compiled function, something during the code patching causes some of the %i* input registers to get corrupted. Perhaps we have a TLB miss path into the firmware that is deep enough to cause a register window spill and subsequent restore when we get back from the TLB miss trap. Let's plug this up by doing two things: 1) Stop using the firmware stack for client interface calls into the firmware. Just use the kernel's stack. 2) As soon as we can, call into a new function "start_early_boot()" to put a one-register-window buffer between the firmware's deepest stack frame and the top-most initial kernel one. Reported-by: Meelis Roos <mroos@linux.ee> Tested-by: Meelis Roos <mroos@linux.ee> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-31sparc64: Increase size of boot string to 1024 bytesDave Kleikamp
[ Upstream commit 1cef94c36bd4d79b5ae3a3df99ee0d76d6a4a6dc ] This is the longest boot string that silo supports. Signed-off-by: Dave Kleikamp <dave.kleikamp@oracle.com> Cc: Bob Picco <bob.picco@oracle.com> Cc: David S. Miller <davem@davemloft.net> Cc: sparclinux@vger.kernel.org Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-31sparc64: Do not define thread fpregs save area as zero-length array.David S. Miller
[ Upstream commit e2653143d7d79a49f1a961aeae1d82612838b12c ] This breaks the stack end corruption detection facility. What that facility does it write a magic value to "end_of_stack()" and checking to see if it gets overwritten. "end_of_stack()" is "task_thread_info(p) + 1", which for sparc64 is the beginning of the FPU register save area. So once the user uses the FPU, the magic value is overwritten and the debug checks trigger. Fix this by making the size explicit. Due to the size we use for the fpsaved[], gsr[], and xfsr[] arrays we are limited to 7 levels of FPU state saves. So each FPU register set is 256 bytes, allocate 256 * 7 for the fpregs area. Reported-by: Meelis Roos <mroos@linux.ee> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-31sparc64: Fix FPU register corruption with AES crypto offload.David S. Miller
[ Upstream commit f4da3628dc7c32a59d1fb7116bb042e6f436d611 ] The AES loops in arch/sparc/crypto/aes_glue.c use a scheme where the key material is preloaded into the FPU registers, and then we loop over and over doing the crypt operation, reusing those pre-cooked key registers. There are intervening blkcipher*() calls between the crypt operation calls. And those might perform memcpy() and thus also try to use the FPU. The sparc64 kernel FPU usage mechanism is designed to allow such recursive uses, but with a catch. There has to be a trap between the two FPU using threads of control. The mechanism works by, when the FPU is already in use by the kernel, allocating a slot for FPU saving at trap time. Then if, within the trap handler, we try to use the FPU registers, the pre-trap FPU register state is saved into the slot. Then at trap return time we notice this and restore the pre-trap FPU state. Over the long term there are various more involved ways we can make this work, but for a quick fix let's take advantage of the fact that the situation where this happens is very limited. All sparc64 chips that support the crypto instructiosn also are using the Niagara4 memcpy routine, and that routine only uses the FPU for large copies where we can't get the source aligned properly to a multiple of 8 bytes. We look to see if the FPU is already in use in this context, and if so we use the non-large copy path which only uses integer registers. Furthermore, we also limit this special logic to when we are doing kernel copy, rather than a user copy. Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-31sparc64: Fix lockdep warnings on reboot on Ultra-5David S. Miller
[ Upstream commit bdcf81b658ebc4c2640c3c2c55c8b31c601b6996 ] Inconsistently, the raw_* IRQ routines do not interact with and update the irqflags tracing and lockdep state, whereas the raw_* spinlock interfaces do. This causes problems in p1275_cmd_direct() because we disable hardirqs by hand using raw_local_irq_restore() and then do a raw_spin_lock() which triggers a lockdep trace because the CPU's hw IRQ state doesn't match IRQ tracing's internal software copy of that state. The CPU's irqs are disabled, yet current->hardirqs_enabled is true. ==================== reboot: Restarting system ------------[ cut here ]------------ WARNING: CPU: 0 PID: 1 at kernel/locking/lockdep.c:3536 check_flags+0x7c/0x240() DEBUG_LOCKS_WARN_ON(current->hardirqs_enabled) Modules linked in: openpromfs CPU: 0 PID: 1 Comm: systemd-shutdow Tainted: G W 3.17.0-dirty #145 Call Trace: [000000000045919c] warn_slowpath_common+0x5c/0xa0 [0000000000459210] warn_slowpath_fmt+0x30/0x40 [000000000048f41c] check_flags+0x7c/0x240 [0000000000493280] lock_acquire+0x20/0x1c0 [0000000000832b70] _raw_spin_lock+0x30/0x60 [000000000068f2fc] p1275_cmd_direct+0x1c/0x60 [000000000068ed28] prom_reboot+0x28/0x40 [000000000043610c] machine_restart+0x4c/0x80 [000000000047d2d4] kernel_restart+0x54/0x80 [000000000047d618] SyS_reboot+0x138/0x200 [00000000004060b4] linux_sparc_syscall32+0x34/0x60 ---[ end trace 5c439fe81c05a100 ]--- possible reason: unannotated irqs-off. irq event stamp: 2010267 hardirqs last enabled at (2010267): [<000000000049a358>] vprintk_emit+0x4b8/0x580 hardirqs last disabled at (2010266): [<0000000000499f08>] vprintk_emit+0x68/0x580 softirqs last enabled at (2010046): [<000000000045d278>] __do_softirq+0x378/0x4a0 softirqs last disabled at (2010039): [<000000000042bf08>] do_softirq_own_stack+0x28/0x40 Resetting ... ==================== Use local_* variables of the hw IRQ interfaces so that IRQ tracing sees all of our changes. Reported-by: Meelis Roos <mroos@linux.ee> Tested-by: Meelis Roos <mroos@linux.ee> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-31sparc64: Fix reversed start/end in flush_tlb_kernel_range()David S. Miller
[ Upstream commit 473ad7f4fb005d1bb727e4ef27d370d28703a062 ] When we have to split up a flush request into multiple pieces (in order to avoid the firmware range) we don't specify the arguments in the right order for the second piece. Fix the order, or else we get hangs as the code tries to flush "a lot" of entries and we get lockups like this: [ 4422.981276] NMI watchdog: BUG: soft lockup - CPU#12 stuck for 23s! [expect:117032] [ 4422.996130] Modules linked in: ipv6 loop usb_storage igb ptp sg sr_mod ehci_pci ehci_hcd pps_core n2_rng rng_core [ 4423.016617] CPU: 12 PID: 117032 Comm: expect Not tainted 3.17.0-rc4+ #1608 [ 4423.030331] task: fff8003cc730e220 ti: fff8003d99d54000 task.ti: fff8003d99d54000 [ 4423.045282] TSTATE: 0000000011001602 TPC: 00000000004521e8 TNPC: 00000000004521ec Y: 00000000 Not tainted [ 4423.064905] TPC: <__flush_tlb_kernel_range+0x28/0x40> [ 4423.074964] g0: 000000000052fd10 g1: 00000001295a8000 g2: ffffff7176ffc000 g3: 0000000000002000 [ 4423.092324] g4: fff8003cc730e220 g5: fff8003dfedcc000 g6: fff8003d99d54000 g7: 0000000000000006 [ 4423.109687] o0: 0000000000000000 o1: 0000000000000000 o2: 0000000000000003 o3: 00000000f0000000 [ 4423.127058] o4: 0000000000000080 o5: 00000001295a8000 sp: fff8003d99d56d01 ret_pc: 000000000052ff54 [ 4423.145121] RPC: <__purge_vmap_area_lazy+0x314/0x3a0> [ 4423.155185] l0: 0000000000000000 l1: 0000000000000000 l2: 0000000000a38040 l3: 0000000000000000 [ 4423.172559] l4: fff8003dae8965e0 l5: ffffffffffffffff l6: 0000000000000000 l7: 00000000f7e2b138 [ 4423.189913] i0: fff8003d99d576a0 i1: fff8003d99d576a8 i2: fff8003d99d575e8 i3: 0000000000000000 [ 4423.207284] i4: 0000000000008008 i5: fff8003d99d575c8 i6: fff8003d99d56df1 i7: 0000000000530c24 [ 4423.224640] I7: <free_vmap_area_noflush+0x64/0x80> [ 4423.234193] Call Trace: [ 4423.239051] [0000000000530c24] free_vmap_area_noflush+0x64/0x80 [ 4423.251029] [0000000000531a7c] remove_vm_area+0x5c/0x80 [ 4423.261628] [0000000000531b80] __vunmap+0x20/0x120 [ 4423.271352] [000000000071cf18] n_tty_close+0x18/0x40 [ 4423.281423] [00000000007222b0] tty_ldisc_close+0x30/0x60 [ 4423.292183] [00000000007225a4] tty_ldisc_reinit+0x24/0xa0 [ 4423.303120] [0000000000722ab4] tty_ldisc_hangup+0xd4/0x1e0 [ 4423.314232] [0000000000719aa0] __tty_hangup+0x280/0x3c0 [ 4423.324835] [0000000000724cb4] pty_close+0x134/0x1a0 [ 4423.334905] [000000000071aa24] tty_release+0x104/0x500 [ 4423.345316] [00000000005511d0] __fput+0x90/0x1e0 [ 4423.354701] [000000000047fa54] task_work_run+0x94/0xe0 [ 4423.365126] [0000000000404b44] __handle_signal+0xc/0x2c Fixes: 4ca9a23765da ("sparc64: Guard against flushing openfirmware mappings.") Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-31sparc: Let memset return the address argumentAndreas Larsson
[ Upstream commit 74cad25c076a2f5253312c2fe82d1a4daecc1323 ] This makes memset follow the standard (instead of returning 0 on success). This is needed when certain versions of gcc optimizes around memset calls and assume that the address argument is preserved in %o0. Signed-off-by: Andreas Larsson <andreas@gaisler.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-31sparc64: Move request_irq() from ldc_bind() to ldc_alloc()Sowmini Varadhan
[ Upstream commit c21c4ab0d6921f7160a43216fa6973b5924de561 ] The request_irq() needs to be done from ldc_alloc() to avoid the following (caught by lockdep) [00000000004a0738] __might_sleep+0xf8/0x120 [000000000058bea4] kmem_cache_alloc_trace+0x184/0x2c0 [00000000004faf80] request_threaded_irq+0x80/0x160 [000000000044f71c] ldc_bind+0x7c/0x220 [0000000000452454] vio_port_up+0x54/0xe0 [00000000101f6778] probe_disk+0x38/0x220 [sunvdc] [00000000101f6b8c] vdc_port_probe+0x22c/0x300 [sunvdc] [0000000000451a88] vio_device_probe+0x48/0x60 [000000000074c56c] really_probe+0x6c/0x300 [000000000074c83c] driver_probe_device+0x3c/0xa0 [000000000074c92c] __driver_attach+0x8c/0xa0 [000000000074a6ec] bus_for_each_dev+0x6c/0xa0 [000000000074c1dc] driver_attach+0x1c/0x40 [000000000074b0fc] bus_add_driver+0xbc/0x280 Signed-off-by: Sowmini Varadhan <sowmini.varadhan@oracle.com> Acked-by: Dwight Engen <dwight.engen@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-31sparc64: find_node adjustmentbob picco
[ Upstream commit 3dee9df54836d5f844f3d58281d3f3e6331b467f ] We have seen an issue with guest boot into LDOM that causes early boot failures because of no matching rules for node identitity of the memory. I analyzed this on my T4 and concluded there might not be a solution. I saw the issue in mainline too when booting into the control/primary domain - with guests configured. Note, this could be a firmware bug on some older machines. I'll provide a full explanation of the issues below. Should we not find a matching BEST latency group for a real address (RA) then we will assume node 0. On the T4-2 here with the information provided I can't see an alternative. Technically the LDOM shown below should match the MBLOCK to the favorable latency group. However other factors must be considered too. Were the memory controllers configured "fine" grained interleave or "coarse" grain interleaved - T4. Also should a "group" MD node be considered a NUMA node? There has to be at least one Machine Description (MD) "group" and hence one NUMA node. The group can have one or more latency groups (lg) - more than one memory controller. The current code chooses the smallest latency as the most favorable per group. The latency and lg information is in MLGROUP below. MBLOCK is the base and size of the RAs for the machine as fetched from OBP /memory "available" property. My machine has one MBLOCK but more would be possible - with holes? For a T4-2 the following information has been gathered: with LDOM guest MEMBLOCK configuration: memory size = 0x27f870000 memory.cnt = 0x3 memory[0x0] [0x00000020400000-0x0000029fc67fff], 0x27f868000 bytes memory[0x1] [0x0000029fd8a000-0x0000029fd8bfff], 0x2000 bytes memory[0x2] [0x0000029fd92000-0x0000029fd97fff], 0x6000 bytes reserved.cnt = 0x2 reserved[0x0] [0x00000020800000-0x000000216c15c0], 0xec15c1 bytes reserved[0x1] [0x00000024800000-0x0000002c180c1e], 0x7980c1f bytes MBLOCK[0]: base[20000000] size[280000000] offset[0] (note: "base" and "size" reported in "MBLOCK" encompass the "memory[X]" values) (note: (RA + offset) & mask = val is the formula to detect a match for the memory controller. should there be no match for find_node node, a return value of -1 resulted for the node - BAD) There is one group. It has these forward links MLGROUP[1]: node[545] latency[1f7e8] match[200000000] mask[200000000] MLGROUP[2]: node[54d] latency[2de60] match[0] mask[200000000] NUMA NODE[0]: node[545] mask[200000000] val[200000000] (latency[1f7e8]) (note: "val" is the best lg's (smallest latency) "match") no LDOM guest - bare metal MEMBLOCK configuration: memory size = 0xfdf2d0000 memory.cnt = 0x3 memory[0x0] [0x00000020400000-0x00000fff6adfff], 0xfdf2ae000 bytes memory[0x1] [0x00000fff6d2000-0x00000fff6e7fff], 0x16000 bytes memory[0x2] [0x00000fff766000-0x00000fff771fff], 0xc000 bytes reserved.cnt = 0x2 reserved[0x0] [0x00000020800000-0x00000021a04580], 0x1204581 bytes reserved[0x1] [0x00000024800000-0x0000002c7d29fc], 0x7fd29fd bytes MBLOCK[0]: base[20000000] size[fe0000000] offset[0] there are two groups group node[16d5] MLGROUP[0]: node[1765] latency[1f7e8] match[0] mask[200000000] MLGROUP[3]: node[177d] latency[2de60] match[200000000] mask[200000000] NUMA NODE[0]: node[1765] mask[200000000] val[0] (latency[1f7e8]) group node[171d] MLGROUP[2]: node[1775] latency[2de60] match[0] mask[200000000] MLGROUP[1]: node[176d] latency[1f7e8] match[200000000] mask[200000000] NUMA NODE[1]: node[176d] mask[200000000] val[200000000] (latency[1f7e8]) (note: for this two "group" bare metal machine, 1/2 memory is in group one's lg and 1/2 memory is in group two's lg). Cc: sparclinux@vger.kernel.org Signed-off-by: Bob Picco <bob.picco@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-31sparc64: Fix corrupted thread fault code.David S. Miller
[ Upstream commit 84bd6d8b9c0f06b3f188efb479c77e20f05e9a8a ] Every path that ends up at do_sparc64_fault() must install a valid FAULT_CODE_* bitmask in the per-thread fault code byte. Two paths leading to the label winfix_trampoline (which expects the FAULT_CODE_* mask in register %g4) were not doing so: 1) For pre-hypervisor TLB protection violation traps, if we took the 'winfix_trampoline' path we wouldn't have %g4 initialized with the FAULT_CODE_* value yet. Resulting in using the TLB_TAG_ACCESS register address value instead. 2) In the TSB miss path, when we notice that we are going to use a hugepage mapping, but we haven't allocated the hugepage TSB yet, we still have to take the window fixup case into consideration and in that particular path we leave %g4 not setup properly. Errors on this sort were largely invisible previously, but after commit 4ccb9272892c33ef1c19a783cfa87103b30c2784 ("sparc64: sun4v TLB error power off events") we now have a fault_code mask bit (FAULT_CODE_BAD_RA) that triggers due to this bug. FAULT_CODE_BAD_RA triggers because this bit is set in TLB_TAG_ACCESS (see #1 above) and thus we get seemingly random bus errors triggered for user processes. Fixes: 4ccb9272892c ("sparc64: sun4v TLB error power off events") Reported-by: Meelis Roos <mroos@linux.ee> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-31sparc64: sun4v TLB error power off eventsbob picco
[ Upstream commit 4ccb9272892c33ef1c19a783cfa87103b30c2784 ] We've witnessed a few TLB events causing the machine to power off because of prom_halt. In one case it was some nfs related area during rmmod. Another was an mmapper of /dev/mem. A more recent one is an ITLB issue with a bad pagesize which could be a hardware bug. Bugs happen but we should attempt to not power off the machine and/or hang it when possible. This is a DTLB error from an mmapper of /dev/mem: [root@sparcie ~]# SUN4V-DTLB: Error at TPC[fffff80100903e6c], tl 1 SUN4V-DTLB: TPC<0xfffff80100903e6c> SUN4V-DTLB: O7[fffff801081979d0] SUN4V-DTLB: O7<0xfffff801081979d0> SUN4V-DTLB: vaddr[fffff80100000000] ctx[1250] pte[98000000000f0610] error[2] . This is recent mainline for ITLB: [ 3708.179864] SUN4V-ITLB: TPC<0xfffffc010071cefc> [ 3708.188866] SUN4V-ITLB: O7[fffffc010071cee8] [ 3708.197377] SUN4V-ITLB: O7<0xfffffc010071cee8> [ 3708.206539] SUN4V-ITLB: vaddr[e0003] ctx[1a3c] pte[2900000dcc800eeb] error[4] . Normally sun4v_itlb_error_report() and sun4v_dtlb_error_report() would call prom_halt() and drop us to OF command prompt "ok". This isn't the case for LDOMs and the machine powers off. For the HV reported error of HV_ENORADDR for HV HV_MMU_MAP_ADDR_TRAP we cause a SIGBUS error by qualifying it within do_sparc64_fault() for fault code mask of FAULT_CODE_BAD_RA. This is done when trap level (%tl) is less or equal one("1"). Otherwise, for %tl > 1, we proceed eventually to die_if_kernel(). The logic of this patch was partially inspired by David Miller's feedback. Power off of large sparc64 machines is painful. Plus die_if_kernel provides more context. A reset sequence isn't a brief period on large sparc64 but better than power-off/power-on sequence. Cc: sparclinux@vger.kernel.org Signed-off-by: Bob Picco <bob.picco@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-31sparc32: dma_alloc_coherent must honour gfp flagsDaniel Hellstrom
[ Upstream commit d1105287aabe88dbb3af825140badaa05cf0442c ] dma_zalloc_coherent() calls dma_alloc_coherent(__GFP_ZERO) but the sparc32 implementations sbus_alloc_coherent() and pci32_alloc_coherent() doesn't take the gfp flags into account. Tested on the SPARC32/LEON GRETH Ethernet driver which fails due to dma_alloc_coherent(__GFP_ZERO) returns non zeroed pages. Signed-off-by: Daniel Hellstrom <daniel@gaisler.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-31sparc64: Fix pcr_ops initialization and usage bugs.David S. Miller
[ Upstream commit 8bccf5b313180faefce38e0d1140f76e0f327d28 ] Christopher reports that perf_event_print_debug() can crash in uniprocessor builds. The crash is due to pcr_ops being NULL. This happens because pcr_arch_init() is only invoked by smp_cpus_done() which only executes in SMP builds. init_hw_perf_events() is closely intertwined with pcr_ops being setup properly, therefore: 1) Call pcr_arch_init() early on from init_hw_perf_events(), instead of from smp_cpus_done(). 2) Do not hook up a PMU type if pcr_ops is NULL after pcr_arch_init(). 3) Move init_hw_perf_events to a later initcall so that it we will be sure to invoke pcr_arch_init() after all cpus are brought up. Finally, guard the one naked sequence of pcr_ops dereferences in __global_pmu_self() with an appropriate NULL check. Reported-by: Christopher Alexander Tobias Schulze <cat.schulze@alice-dsl.net> Signed-off-by: David S. Miller <davem@davemloft.net>