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2016-06-17powerpc/eeh: Fix invalid cached PE primary busGavin Shan1-3/+4
The PE primary bus cannot be got from its child devices when having full hotplug in error recovery. The PE primary bus is cached, which is done in commit <05ba75f84864> ("powerpc/eeh: Fix stale cached primary bus"). In eeh_reset_device(), the flag (EEH_PE_PRI_BUS) is cleared before the PCI hot remove. eeh_pe_bus_get() then returns NULL as the PE primary bus in pnv_eeh_reset() and it crashes the kernel eventually. This fixes the issue by clearing the flag (EEH_PE_PRI_BUS) before the PCI hot add. With it, the PowerNV EEH reset backend (pnv_eeh_reset()) can get valid PE primary bus through eeh_pe_bus_get(). Fixes: 67086e32b564 ("powerpc/eeh: powerpc/eeh: Support error recovery for VF PE") Reported-by: Pridhiviraj Paidipeddi <ppaiddipe@in.ibm.com> Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-06-17powerpc/mm/radix: Update Radix tree size as per ISA 3.0Aneesh Kumar K.V3-7/+19
ISA 3.0 updated it to be encoded as Radix tree size = 2^(RTS + 31). We have it encoded as 2^(RTS + 28). Add a helper with the correct encoding and use it instead of opencoding. Fixes: 2bfd65e45e87 ("powerpc/mm/radix: Add radix callbacks for early init routines") Reviewed-by: Balbir Singh <bsingharora@gmail.com> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-06-17powerpc/mm/hash: Don't add memory coherence if cache inhibited is setAneesh Kumar K.V1-5/+9
H_ENTER hcall handling in qemu had assumptions that a cache inhibited hpte entry won't have memory conference set. Also older kernel mentioned that some version of pHyp required this (the code removed by the below commit says: /* Make pHyp happy */ if ((rflags & _PAGE_NO_CACHE) && !(rflags & _PAGE_WRITETHRU)) hpte_r &= ~HPTE_R_M; But with older kernel we had some inconsistent memory conherence mapping. We always enabled memory conherence in the page fault path and removed memory conherence is _PAGE_NO_CACHE was set when we mapped the page via htab_bolt_mapping. The commit mentioned below tried to consolidate that by always enabling memory conherence. But as mentioned above that breaks Qemu H_ENTER handling. This patch update this such that we enable memory conherence only if cache inhibited is not set and bring fault handling, lpar and bolt mapping in sync. Fixes: commit 30bda41aba4e("powerpc/mm: Drop WIMG in favour of new constant") Reported-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-06-14powerpc/mm/hash: Use the correct PPP mask when updating HPTEAneesh Kumar K.V2-4/+5
With commit e58e87adc8bf9 "powerpc/mm: Update _PAGE_KERNEL_RO" we now use all the three PPP bits. The top bit is now used to have a PPP value of 0b110 which will be mapped to kernel read only. When updating the hpte entry use right mask such that we update the 63rd bit (top 'P' bit) too. Prior to e58e87adc8bf we didn't support KERNEL_RO at all (it was == KERNEL_RW), so this isn't a regression as such. Fixes: e58e87adc8bf ("powerpc/mm: Update _PAGE_KERNEL_RO") Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-06-10powerpc/mm/radix: Flush page walk cache when freeing page tableAneesh Kumar K.V6-7/+73
Even though a tlb_flush() does a flush with invalidate all cache, we can end up doing an RCU page table free before calling tlb_flush(). That means we can have page walk cache entries even after we free the page table pages. This can result in us doing wrong page table walk. Avoid this by doing pwc flush on every page table free. We can't batch the pwc flush, because the rcu call back function where we free the page table pages doesn't have information of the mmu gather. Thus we have to do a pwc on every page table page freed. Note: I also removed the dummy tlb_flush_pgtable call functions for hash 32. Fixes: 1a472c9dba6b ("powerpc/mm/radix: Add tlbflush routines") Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-06-10powerpc/mm/radix: Update to tlb functions ric argumentAneesh Kumar K.V1-21/+22
Radix invalidate control (RIC) is used to control which cache to flush using tlb instructions. When doing a PID flush, we currently flush everything including page walk cache. For address range flush, we flush only the TLB. In the next patch, we add support for flushing only the page walk cache. Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-06-10powerpc/nohash: Fix build break with 64K pagesMichael Ellerman1-1/+1
Commit 74701d5947a6 "powerpc/mm: Rename function to indicate we are allocating fragments" renamed page_table_free() to pte_fragment_free(). One occurrence was mistyped as pte_fragment_fre(). This only breaks the nohash 64K page build, which is not the default or enabled in any defconfig. Fixes: 74701d5947a6 ("powerpc/mm: Rename function to indicate we are allocating fragments") Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-06-08powerpc/mm/hash: Compute the segment size correctly for ISA 3.0Aneesh Kumar K.V1-1/+5
PowerISA 3.0 encodes the segment size in the second half of hash page table entry. Update hpte_decode() accordingly. Fixes: 50de596de8be ("powerpc/mm/hash: Add support for Power9 Hash") Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-06-08powerpc/mm/radix: Fix always false comparison against MMU_NO_CONTEXTAneesh Kumar K.V1-4/+4
In some of the radix TLB flush routines, we use a local to store the mm->context.id, AKA the PID. Currently we use an int, but the PID is unsigned long, so large values of PID will be truncated. In particular MMU_NO_CONTEXT is -1, which means all our comparisons against that value can never be true. This means we'll issue TLB flushes when we shouldn't on radix enabled machines. Fix it by using an unsigned long for the local. Discovered by Coverity. Fixes: 1a472c9dba6b ("powerpc/mm/radix: Add tlbflush routines") Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Reviewed-by: Balbir Singh <bsingharora@gmail.com> [mpe: Write change log] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-06-08of: fix autoloading due to broken modalias with no 'compatible'Wolfram Sang1-1/+1
Because of an improper dereference, a stray 'C' character was output to the modalias when no 'compatible' was specified. This is the case for some old PowerMac drivers which only set the 'name' property. Fix it to let them match again. Reported-by: Mathieu Malaterre <malat@debian.org> Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Tested-by: Mathieu Malaterre <malat@debian.org> Cc: Philipp Zabel <p.zabel@pengutronix.de> Cc: Andreas Schwab <schwab@linux-m68k.org> Fixes: 6543becf26fff6 ("mod/file2alias: make modalias generation safe for cross compiling") Cc: stable@vger.kernel.org # v3.9+ Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-06-08powerpc/pseries: Fix IBM_ARCH_VEC_NRCORES_OFFSET since POWER8NVL was addedMichael Ellerman1-1/+1
The recent commit 7cc851039d64 ("powerpc/pseries: Add POWER8NVL support to ibm,client-architecture-support call") added a new PVR mask & value to the start of the ibm_architecture_vec[] array. However it missed the fact that further down in the array, we hard code the offset of one of the fields, and then at boot use that value to patch the value in the array. This means every update to the array must also update the #define, ugh. This means that on pseries machines we will misreport to firmware the number of cores we support, by a factor of threads_per_core. Fix it for now by updating the #define. Fixes: 7cc851039d64 ("powerpc/pseries: Add POWER8NVL support to ibm,client-architecture-support call") Cc: stable@vger.kernel.org # v4.0+ Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-06-06powerpc/pseries: Fix PCI config address for DDWGavin Shan1-2/+2
In commit 8445a87f7092 "powerpc/iommu: Remove the dependency on EEH struct in DDW mechanism", the PE address was replaced with the PCI config address in order to remove dependency on EEH. According to PAPR spec, firmware (pHyp or QEMU) should accept "xxBBSSxx" format PCI config address, not "xxxxBBSS" provided by the patch. Note that "BB" is PCI bus number and "SS" is the combination of slot and function number. This fixes the PCI address passed to DDW RTAS calls. Fixes: 8445a87f7092 ("powerpc/iommu: Remove the dependency on EEH struct in DDW mechanism") Cc: stable@vger.kernel.org # v3.4+ Reported-by: Guilherme G. Piccoli <gpiccoli@linux.vnet.ibm.com> Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com> Tested-by: Guilherme G. Piccoli <gpiccoli@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-06-06powerpc/ptrace: Fix out of bounds array access warningKhem Raj1-2/+2
gcc-6 correctly warns about a out of bounds access arch/powerpc/kernel/ptrace.c:407:24: warning: index 32 denotes an offset greater than size of 'u64[32][1] {aka long long unsigned int[32][1]}' [-Warray-bounds] offsetof(struct thread_fp_state, fpr[32][0])); ^ check the end of array instead of beginning of next element to fix this Signed-off-by: Khem Raj <raj.khem@gmail.com> Cc: Kees Cook <keescook@chromium.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Segher Boessenkool <segher@kernel.crashing.org> Tested-by: Aaro Koskinen <aaro.koskinen@iki.fi> Acked-by: Olof Johansson <olof@lixom.net> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-06-01powerpc/pseries: Add POWER8NVL support to ibm,client-architecture-support callThomas Huth1-0/+1
If we do not provide the PVR for POWER8NVL, a guest on this system currently ends up in PowerISA 2.06 compatibility mode on KVM, since QEMU does not provide a generic PowerISA 2.07 mode yet. So some new instructions from POWER8 (like "mtvsrd") get disabled for the guest, resulting in crashes when using code compiled explicitly for POWER8 (e.g. with the "-mcpu=power8" option of GCC). Fixes: ddee09c099c3 ("powerpc: Add PVR for POWER8NVL processor") Cc: stable@vger.kernel.org # v4.0+ Signed-off-by: Thomas Huth <thuth@redhat.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-06-01powerpc/mm/radix: Add missing tlb flushAneesh Kumar K.V1-4/+1
This should not have any impact on hash, because hash does tlb invalidate with every pte update and we don't implement flush_tlb_* functions for hash. With radix we should make an explicit call to flush tlb outside pte update. Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-06-01powerpc/mm/hash: Fix the reference bit update when handling hash faultAneesh Kumar K.V1-2/+20
When we converted the asm routines to C functions, we missed updating HPTE_R_R based on _PAGE_ACCESSED. ASM code used to copy over the lower bits from pte via. andi. r3,r30,0x1fe /* Get basic set of flags */ We also update the code such that we won't update the Change bit ('C' bit) always. This was added by commit c5cf0e30bf3d8 ("powerpc: Fix buglet with MMU hash management"). With hash64, we need to make sure that hardware doesn't do a pte update directly. This is because we do end up with entries in TLB with no hash page table entry. This happens because when we find a hash bucket full, we "evict" a more/less random entry from it. When we do that we don't invalidate the TLB (hpte_remove) because we assume the old translation is still technically "valid". For more info look at commit 0608d692463("powerpc/mm: Always invalidate tlb on hpte invalidate and update"). Thus it's critical that valid hash PTEs always have reference bit set and writeable ones have change bit set. We do this by hashing a non-dirty linux PTE as read-only and always setting _PAGE_ACCESSED (and thus R) when hashing anything else in. Any attempt by Linux at clearing those bits also removes the corresponding hash entry. Commit 5cf0e30bf3d8 did that for 'C' bit by enabling 'C' bit always. We don't really need to do that because we never map a RW pte entry without setting 'C' bit. On READ fault on a RW pte entry, we still map it READ only, hence a store update in the page will still cause a hash pte fault. This patch reverts the part of commit c5cf0e30bf3d8 ("[PATCH] powerpc: Fix buglet with MMU hash management") and retain the updatepp part. - If we hit the updatepp path on native, the old code without that commit, would fail to set C bcause native_hpte_updatepp() was implemented to filter the same bits as H_PROTECT and not let C through thus we would "upgrade" a RO HPTE to RW without setting C thus causing the bug. So the real fix in that commit was the change to native_hpte_updatepp Fixes: 89ff725051d1 ("powerpc/mm: Convert __hash_page_64K to C") Cc: stable@vger.kernel.org # v4.5+ Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-06-01powerpc/mm/radix: Update LPCR only if it is powernvAneesh Kumar K.V1-13/+10
LPCR cannot be updated when running in guest mode. Fixes: 2bfd65e45e87 ("powerpc/mm/radix: Add radix callbacks for early init routines") Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-05-31powerpc: Use privileged SPR number for MMCR2Thomas Huth1-1/+1
We are already using the privileged versions of MMCR0, MMCR1 and MMCRA in the kernel, so for MMCR2, we should better use the privileged versions, too, to be consistent. Fixes: 240686c13687 ("powerpc: Initialise PMU related regs on Power8") Cc: stable@vger.kernel.org # v3.10+ Suggested-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Thomas Huth <thuth@redhat.com> Acked-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-05-31powerpc: Fix definition of SIAR and SDAR registersThomas Huth1-2/+2
The SIAR and SDAR registers are available twice, one time as SPRs 780 / 781 (unprivileged, but read-only), and one time as the SPRs 796 / 797 (privileged, but read and write). The Linux kernel code currently uses the unprivileged SPRs - while this is OK for reading, writing to that register of course does not work. Since the KVM code tries to write to this register, too (see the mtspr in book3s_hv_rmhandlers.S), the contents of this register sometimes get lost for the guests, e.g. during migration of a VM. To fix this issue, simply switch to the privileged SPR numbers instead. Cc: stable@vger.kernel.org Signed-off-by: Thomas Huth <thuth@redhat.com> Acked-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-05-30powerpc/pseries/eeh: Refactor the configure_bridge RTAS tokensRussell Currey1-16/+12
The RTAS calls "ibm,configure-pe" and "ibm,configure-bridge" perform the same actions, however the former can skip configuration if unnecessary. The existing code treats them as different tokens even though only one will ever be called. Refactor this by making a single token that is assigned during init. Signed-off-by: Russell Currey <ruscur@russell.cc> Acked-by: Gavin Shan <gwshan@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-05-30powerpc/pseries/eeh: Handle RTAS delay requests in configure_bridgeRussell Currey1-15/+36
In the "ibm,configure-pe" and "ibm,configure-bridge" RTAS calls, the spec states that values of 9900-9905 can be returned, indicating that software should delay for 10^x (where x is the last digit, i.e. 990x) milliseconds and attempt the call again. Currently, the kernel doesn't know about this, and respecting it fixes some PCI failures when the hypervisor is busy. The delay is capped at 0.2 seconds. Cc: <stable@vger.kernel.org> # 3.10+ Signed-off-by: Russell Currey <ruscur@russell.cc> Acked-by: Gavin Shan <gwshan@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-05-29Linux 4.7-rc1v4.7-rc1Linus Torvalds1-3/+3
2016-05-29hash_string: Fix zero-length case for !DCACHE_WORD_ACCESSGeorge Spelvin1-2/+2
The self-test was updated to cover zero-length strings; the function needs to be updated, too. Reported-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: George Spelvin <linux@sciencehorizons.net> Fixes: fcfd2fbf22d2 ("fs/namei.c: Add hashlen_string() function") Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-05-28Rename other copy of hash_string to hashlen_stringGeorge Spelvin1-2/+2
The original name was simply hash_string(), but that conflicted with a function with that name in drivers/base/power/trace.c, and I decided that calling it "hashlen_" was better anyway. But you have to do it in two places. [ This caused build errors for architectures that don't define CONFIG_DCACHE_WORD_ACCESS - Linus ] Signed-off-by: George Spelvin <linux@sciencehorizons.net> Reported-by: Guenter Roeck <linux@roeck-us.net> Fixes: fcfd2fbf22d2 ("fs/namei.c: Add hashlen_string() function") Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-05-28hpfs: implement the show_options methodMikulas Patocka1-11/+32
The HPFS filesystem used generic_show_options to produce string that is displayed in /proc/mounts. However, there is a problem that the options may disappear after remount. If we mount the filesystem with option1 and then remount it with option2, /proc/mounts should show both option1 and option2, however it only shows option2 because the whole option string is replaced with replace_mount_options in hpfs_remount_fs. To fix this bug, implement the hpfs_show_options function that prints options that are currently selected. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Cc: stable@vger.kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-05-28affs: fix remount failure when there are no options changedMikulas Patocka1-2/+3
Commit c8f33d0bec99 ("affs: kstrdup() memory handling") checks if the kstrdup function returns NULL due to out-of-memory condition. However, if we are remounting a filesystem with no change to filesystem-specific options, the parameter data is NULL. In this case, kstrdup returns NULL (because it was passed NULL parameter), although no out of memory condition exists. The mount syscall then fails with ENOMEM. This patch fixes the bug. We fail with ENOMEM only if data is non-NULL. The patch also changes the call to replace_mount_options - if we didn't pass any filesystem-specific options, we don't call replace_mount_options (thus we don't erase existing reported options). Fixes: c8f33d0bec99 ("affs: kstrdup() memory handling") Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Cc: stable@vger.kernel.org # v4.1+ Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-05-28hpfs: fix remount failure when there are no options changedMikulas Patocka1-2/+3
Commit ce657611baf9 ("hpfs: kstrdup() out of memory handling") checks if the kstrdup function returns NULL due to out-of-memory condition. However, if we are remounting a filesystem with no change to filesystem-specific options, the parameter data is NULL. In this case, kstrdup returns NULL (because it was passed NULL parameter), although no out of memory condition exists. The mount syscall then fails with ENOMEM. This patch fixes the bug. We fail with ENOMEM only if data is non-NULL. The patch also changes the call to replace_mount_options - if we didn't pass any filesystem-specific options, we don't call replace_mount_options (thus we don't erase existing reported options). Fixes: ce657611baf9 ("hpfs: kstrdup() out of memory handling") Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Cc: stable@vger.kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-05-28Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linusLinus Torvalds67-258/+373
Pull more MIPS updates from Ralf Baechle: "This is the secondnd batch of MIPS patches for 4.7. Summary: CPS: - Copy EVA configuration when starting secondary VPs. EIC: - Clear Status IPL. Lasat: - Fix a few off by one bugs. lib: - Mark intrinsics notrace. Not only are the intrinsics uninteresting, it would cause infinite recursion. MAINTAINERS: - Add file patterns for MIPS BRCM device tree bindings. - Add file patterns for mips device tree bindings. MT7628: - Fix MT7628 pinmux typos. - wled_an pinmux gpio. - EPHY LEDs pinmux support. Pistachio: - Enable KASLR VDSO: - Build microMIPS VDSO for microMIPS kernels. - Fix aliasing warning by building with `-fno-strict-aliasing' for debugging but also tracing them might result in recursion. Misc: - Add missing FROZEN hotplug notifier transitions. - Fix clk binding example for varioius PIC32 devices. - Fix cpu interrupt controller node-names in the DT files. - Fix XPA CPU feature separation. - Fix write_gc0_* macros when writing zero. - Add inline asm encoding helpers. - Add missing VZ accessor microMIPS encodings. - Fix little endian microMIPS MSA encodings. - Add 64-bit HTW fields and fix its configuration. - Fix sigreturn via VDSO on microMIPS kernel. - Lots of typo fixes. - Add definitions of SegCtl registers and use them" * 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus: (49 commits) MIPS: Add missing FROZEN hotplug notifier transitions MIPS: Build microMIPS VDSO for microMIPS kernels MIPS: Fix sigreturn via VDSO on microMIPS kernel MIPS: devicetree: fix cpu interrupt controller node-names MIPS: VDSO: Build with `-fno-strict-aliasing' MIPS: Pistachio: Enable KASLR MIPS: lib: Mark intrinsics notrace MIPS: Fix 64-bit HTW configuration MIPS: Add 64-bit HTW fields MAINTAINERS: Add file patterns for mips device tree bindings MAINTAINERS: Add file patterns for mips brcm device tree bindings MIPS: Simplify DSP instruction encoding macros MIPS: Add missing tlbinvf/XPA microMIPS encodings MIPS: Fix little endian microMIPS MSA encodings MIPS: Add missing VZ accessor microMIPS encodings MIPS: Add inline asm encoding helpers MIPS: Spelling fix lets -> let's MIPS: VR41xx: Fix typo MIPS: oprofile: Fix typo MIPS: math-emu: Fix typo ...
2016-05-28fs: fix binfmt_aout.c build errorGuenter Roeck1-1/+0
Various builds (such as i386:allmodconfig) fail with fs/binfmt_aout.c:133:2: error: expected identifier or '(' before 'return' fs/binfmt_aout.c:134:1: error: expected identifier or '(' before '}' token [ Oops. My bad, I had stupidly thought that "allmodconfig" covered this on x86-64 too, but it obviously doesn't. Egg on my face. - Linus ] Fixes: 5d22fc25d4fc ("mm: remove more IS_ERR_VALUE abuses") Signed-off-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-05-28Merge branch 'hash' of git://ftp.sciencehorizons.net/linuxLinus Torvalds17-150/+734
Pull string hash improvements from George Spelvin: "This series does several related things: - Makes the dcache hash (fs/namei.c) useful for general kernel use. (Thanks to Bruce for noticing the zero-length corner case) - Converts the string hashes in <linux/sunrpc/svcauth.h> to use the above. - Avoids 64-bit multiplies in hash_64() on 32-bit platforms. Two 32-bit multiplies will do well enough. - Rids the world of the bad hash multipliers in hash_32. This finishes the job started in commit 689de1d6ca95 ("Minimal fix-up of bad hashing behavior of hash_64()") The vast majority of Linux architectures have hardware support for 32x32-bit multiply and so derive no benefit from "simplified" multipliers. The few processors that do not (68000, h8/300 and some models of Microblaze) have arch-specific implementations added. Those patches are last in the series. - Overhauls the dcache hash mixing. The patch in commit 0fed3ac866ea ("namei: Improve hash mixing if CONFIG_DCACHE_WORD_ACCESS") was an off-the-cuff suggestion. Replaced with a much more careful design that's simultaneously faster and better. (My own invention, as there was noting suitable in the literature I could find. Comments welcome!) - Modify the hash_name() loop to skip the initial HASH_MIX(). This would let us salt the hash if we ever wanted to. - Sort out partial_name_hash(). The hash function is declared as using a long state, even though it's truncated to 32 bits at the end and the extra internal state contributes nothing to the result. And some callers do odd things: - fs/hfs/string.c only allocates 32 bits of state - fs/hfsplus/unicode.c uses it to hash 16-bit unicode symbols not bytes - Modify bytemask_from_count to handle inputs of 1..sizeof(long) rather than 0..sizeof(long)-1. This would simplify users other than full_name_hash" Special thanks to Bruce Fields for testing and finding bugs in v1. (I learned some humbling lessons about "obviously correct" code.) On the arch-specific front, the m68k assembly has been tested in a standalone test harness, I've been in contact with the Microblaze maintainers who mostly don't care, as the hardware multiplier is never omitted in real-world applications, and I haven't heard anything from the H8/300 world" * 'hash' of git://ftp.sciencehorizons.net/linux: h8300: Add <asm/hash.h> microblaze: Add <asm/hash.h> m68k: Add <asm/hash.h> <linux/hash.h>: Add support for architecture-specific functions fs/namei.c: Improve dcache hash function Eliminate bad hash multipliers from hash_32() and hash_64() Change hash_64() return value to 32 bits <linux/sunrpc/svcauth.h>: Define hash_str() in terms of hashlen_string() fs/namei.c: Add hashlen_string() function Pull out string hash to <linux/stringhash.h>
2016-05-28h8300: Add <asm/hash.h>George Spelvin2-0/+54
This will improve the performance of hash_32() and hash_64(), but due to complete lack of multi-bit shift instructions on H8, performance will still be bad in surrounding code. Designing H8-specific hash algorithms to work around that is a separate project. (But if the maintainers would like to get in touch...) Signed-off-by: George Spelvin <linux@sciencehorizons.net> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Cc: uclinux-h8-devel@lists.sourceforge.jp
2016-05-28microblaze: Add <asm/hash.h>George Spelvin2-0/+82
Microblaze is an FPGA soft core that can be configured various ways. If it is configured without a multiplier, the standard __hash_32() will require a call to __mulsi3, which is a slow software loop. Instead, use a shift-and-add sequence for the constant multiply. GCC knows how to do this, but it's not as clever as some. Signed-off-by: George Spelvin <linux@sciencehorizons.net> Cc: Alistair Francis <alistair.francis@xilinx.com> Cc: Michal Simek <michal.simek@xilinx.com>
2016-05-28m68k: Add <asm/hash.h>George Spelvin2-0/+60
This provides a multiply by constant GOLDEN_RATIO_32 = 0x61C88647 for the original mc68000, which lacks a 32x32-bit multiply instruction. Yes, the amount of optimization effort put in is excessive. :-) Shift-add chain found by Yevgen Voronenko's Hcub algorithm at http://spiral.ece.cmu.edu/mcm/gen.html Signed-off-by: George Spelvin <linux@sciencehorizons.net> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Greg Ungerer <gerg@linux-m68k.org> Cc: Andreas Schwab <schwab@linux-m68k.org> Cc: Philippe De Muyter <phdm@macq.eu> Cc: linux-m68k@lists.linux-m68k.org
2016-05-28<linux/hash.h>: Add support for architecture-specific functionsGeorge Spelvin6-4/+299
This is just the infrastructure; there are no users yet. This is modelled on CONFIG_ARCH_RANDOM; a CONFIG_ symbol declares the existence of <asm/hash.h>. That file may define its own versions of various functions, and define HAVE_* symbols (no CONFIG_ prefix!) to suppress the generic ones. Included is a self-test (in lib/test_hash.c) that verifies the basics. It is NOT in general required that the arch-specific functions compute the same thing as the generic, but if a HAVE_* symbol is defined with the value 1, then equality is tested. Signed-off-by: George Spelvin <linux@sciencehorizons.net> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Greg Ungerer <gerg@linux-m68k.org> Cc: Andreas Schwab <schwab@linux-m68k.org> Cc: Philippe De Muyter <phdm@macq.eu> Cc: linux-m68k@lists.linux-m68k.org Cc: Alistair Francis <alistai@xilinx.com> Cc: Michal Simek <michal.simek@xilinx.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Cc: uclinux-h8-devel@lists.sourceforge.jp
2016-05-28fs/namei.c: Improve dcache hash functionGeorge Spelvin1-40/+81
Patch 0fed3ac866 improved the hash mixing, but the function is slower than necessary; there's a 7-instruction dependency chain (10 on x86) each loop iteration. Word-at-a-time access is a very tight loop (which is good, because link_path_walk() is one of the hottest code paths in the entire kernel), and the hash mixing function must not have a longer latency to avoid slowing it down. There do not appear to be any published fast hash functions that: 1) Operate on the input a word at a time, and 2) Don't need to know the length of the input beforehand, and 3) Have a single iterated mixing function, not needing conditional branches or unrolling to distinguish different loop iterations. One of the algorithms which comes closest is Yann Collet's xxHash, but that's two dependent multiplies per word, which is too much. The key insights in this design are: 1) Barring expensive ops like multiplies, to diffuse one input bit across 64 bits of hash state takes at least log2(64) = 6 sequentially dependent instructions. That is more cycles than we'd like. 2) An operation like "hash ^= hash << 13" requires a second temporary register anyway, and on a 2-operand machine like x86, it's three instructions. 3) A better use of a second register is to hold a two-word hash state. With careful design, no temporaries are needed at all, so it doesn't increase register pressure. And this gets rid of register copying on 2-operand machines, so the code is smaller and faster. 4) Using two words of state weakens the requirement for one-round mixing; we now have two rounds of mixing before cancellation is possible. 5) A two-word hash state also allows operations on both halves to be done in parallel, so on a superscalar processor we get more mixing in fewer cycles. I ended up using a mixing function inspired by the ChaCha and Speck round functions. It is 6 simple instructions and 3 cycles per iteration (assuming multiply by 9 can be done by an "lea" instruction): x ^= *input++; y ^= x; x = ROL(x, K1); x += y; y = ROL(y, K2); y *= 9; Not only is this reversible, two consecutive rounds are reversible: if you are given the initial and final states, but not the intermediate state, it is possible to compute both input words. This means that at least 3 words of input are required to create a collision. (It also has the property, used by hash_name() to avoid a branch, that it hashes all-zero to all-zero.) The rotate constants K1 and K2 were found by experiment. The search took a sample of random initial states (I used 1023) and considered the effect of flipping each of the 64 input bits on each of the 128 output bits two rounds later. Each of the 8192 pairs can be considered a biased coin, and adding up the Shannon entropy of all of them produces a score. The best-scoring shifts also did well in other tests (flipping bits in y, trying 3 or 4 rounds of mixing, flipping all 64*63/2 pairs of input bits), so the choice was made with the additional constraint that the sum of the shifts is odd and not too close to the word size. The final state is then folded into a 32-bit hash value by a less carefully optimized multiply-based scheme. This also has to be fast, as pathname components tend to be short (the most common case is one iteration!), but there's some room for latency, as there is a fair bit of intervening logic before the hash value is used for anything. (Performance verified with "bonnie++ -s 0 -n 1536:-2" on tmpfs. I need a better benchmark; the numbers seem to show a slight dip in performance between 4.6.0 and this patch, but they're too noisy to quote.) Special thanks to Bruce fields for diligent testing which uncovered a nasty fencepost error in an earlier version of this patch. [checkpatch.pl formatting complaints noted and respectfully disagreed with.] Signed-off-by: George Spelvin <linux@sciencehorizons.net> Tested-by: J. Bruce Fields <bfields@redhat.com>
2016-05-28Eliminate bad hash multipliers from hash_32() and hash_64()George Spelvin2-53/+36
The "simplified" prime multipliers made very bad hash functions, so get rid of them. This completes the work of 689de1d6ca. To avoid the inefficiency which was the motivation for the "simplified" multipliers, hash_64() on 32-bit systems is changed to use a different algorithm. It makes two calls to hash_32() instead. drivers/media/usb/dvb-usb-v2/af9015.c uses the old GOLDEN_RATIO_PRIME_32 for some horrible reason, so it inherits a copy of the old definition. Signed-off-by: George Spelvin <linux@sciencehorizons.net> Cc: Antti Palosaari <crope@iki.fi> Cc: Mauro Carvalho Chehab <m.chehab@samsung.com>
2016-05-28Change hash_64() return value to 32 bitsGeorge Spelvin1-3/+3
That's all that's ever asked for, and it makes the return type of hash_long() consistent. It also allows (upcoming patch) an optimized implementation of hash_64 on 32-bit machines. I tried adding a BUILD_BUG_ON to ensure the number of bits requested was never more than 32 (most callers use a compile-time constant), but adding <linux/bug.h> to <linux/hash.h> breaks the tools/perf compiler unless tools/perf/MANIFEST is updated, and understanding that code base well enough to update it is too much trouble. I did the rest of an allyesconfig build with such a check, and nothing tripped. Signed-off-by: George Spelvin <linux@sciencehorizons.net>
2016-05-28<linux/sunrpc/svcauth.h>: Define hash_str() in terms of hashlen_string()George Spelvin1-31/+9
Finally, the first use of previous two patches: eliminate the separate ad-hoc string hash functions in the sunrpc code. Now hash_str() is a wrapper around hash_string(), and hash_mem() is likewise a wrapper around full_name_hash(). Note that sunrpc code *does* call hash_mem() with a zero length, which is why the previous patch needed to handle that in full_name_hash(). (Thanks, Bruce, for finding that!) This also eliminates the only caller of hash_long which asks for more than 32 bits of output. The comment about the quality of hashlen_string() and full_name_hash() is jumping the gun by a few patches; they aren't very impressive now, but will be improved greatly later in the series. Signed-off-by: George Spelvin <linux@sciencehorizons.net> Tested-by: J. Bruce Fields <bfields@redhat.com> Acked-by: J. Bruce Fields <bfields@redhat.com> Cc: Jeff Layton <jlayton@poochiereds.net> Cc: linux-nfs@vger.kernel.org
2016-05-28fs/namei.c: Add hashlen_string() functionGeorge Spelvin3-9/+53
We'd like to make more use of the highly-optimized dcache hash functions throughout the kernel, rather than have every subsystem create its own, and a function that hashes basic null-terminated strings is required for that. (The name is to emphasize that it returns both hash and length.) It's actually useful in the dcache itself, specifically d_alloc_name(). Other uses in the next patch. full_name_hash() is also tweaked to make it more generally useful: 1) Take a "char *" rather than "unsigned char *" argument, to be consistent with hash_name(). 2) Handle zero-length inputs. If we want more callers, we don't want to make them worry about corner cases. Signed-off-by: George Spelvin <linux@sciencehorizons.net>
2016-05-28Pull out string hash to <linux/stringhash.h>George Spelvin2-26/+73
... so they can be used without the rest of <linux/dcache.h> The hashlen_* macros will make sense next patch. Signed-off-by: George Spelvin <linux@sciencehorizons.net>
2016-05-28Merge branch 'i2c/for-next' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux Pull i2c fix from Wolfram Sang: "A fix for a regression introduced yesterday. The regression didn't show up here locally because I did not have PAGE_POISONING enabled. And buildbots discovered this only after it hit your tree. Thanks to Dan for the quick response" * 'i2c/for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: i2c: dev: use after free in detach
2016-05-28Merge tag 'chrome-platform' of ↵Linus Torvalds9-17/+234
git://git.kernel.org/pub/scm/linux/kernel/git/olof/chrome-platform Pull chrome platform updates from Olof Johansson "A handful of Chrome driver and binding changes this merge window: - a few patches to fix probing and configuration of pstore - a few patches adding Elan touchpad registration on a few devices - EC changes: a security fix dealing with max message sizes and addition of compat_ioctl support. - keyboard backlight control support There was also an accidential duplicate registration of trackpads on 'Leon', which was reverted just recently" * tag 'chrome-platform' of git://git.kernel.org/pub/scm/linux/kernel/git/olof/chrome-platform: Revert "platform/chrome: chromeos_laptop: Add Leon Touch" platform/chrome: chromeos_laptop - Add Elan touchpad for Wolf platform/chrome: chromeos_laptop - Add elan trackpad option for C720 platform/chrome: cros_ec_dev - Populate compat_ioctl platform/chrome: cros_ec_lightbar - use name instead of ID to hide lightbar attributes platform/chrome: cros_ec_dev - Fix security issue platform/chrome: Add Chrome OS keyboard backlight LEDs support platform/chrome: use to_platform_device() platform/chrome: pstore: Move to larger record size. platform/chrome: pstore: probe for ramoops buffer using acpi platform/chrome: chromeos_laptop: Add Leon Touch
2016-05-28Merge tag 'sound-4.7-rc1-2' of ↵Linus Torvalds56-331/+2800
git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound Pull more sound updates from Takashi Iwai: "This is the second update round for 4.7-rc1. Most of changes are about the pending ASoC updates and fixes, including a few new drivers. Below are some highlights: ASoC: - New drivers for MAX98371 and TAS5720 - SPI support for TLV320AIC32x4, along with the module split - TDM support for STI Uniperf IPs - Remaining topology API fixes / updates HDA: - A couple of Dell quirks and new Realtek codec support" * tag 'sound-4.7-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound: (63 commits) ALSA: hda - Fix headset mic detection problem for one Dell machine spi: spi-ep93xx: Fix the PTR_ERR() argument ALSA: hda/realtek - Add support for ALC295/ALC3254 ASoC: kirkwood: fix build failure ALSA: hda - Fix headphone noise on Dell XPS 13 9360 ASoC: ak4642: Enable cache usage to fix crashes on resume ASoC: twl6040: Disconnect AUX output pads on digital mute ASoC: tlv320aic32x4: Properly implement the positive and negative pins into the mixers rcar: src: skip disabled-SRC nodes ASoC: max98371 Remove duplicate entry in max98371_reg ASoC: twl6040: Select LPPLL during standby ASoC: rsnd: don't use prohibited number to PDMACHCRn.SRS ASoC: simple-card: Add pm callbacks to platform driver ASoC: pxa: Fix module autoload for platform drivers ASoC: topology: Fix memory leak in widget creation ASoC: Add max98371 codec driver ASoC: rsnd: count .probe/.remove for rsnd_mod_call() ASoC: topology: Check size mismatch of ABI objects before parsing ASoC: topology: Check failure to create a widget ASoC: add support for TAS5720 digital amplifier ...
2016-05-28Merge branch 'for-next' of ↵Linus Torvalds46-814/+5737
git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending Pull SCSI target updates from Nicholas Bellinger: "Here are the outstanding target pending updates for v4.7-rc1. The highlights this round include: - Allow external PR/ALUA metadata path be defined at runtime via top level configfs attribute (Lee) - Fix target session shutdown bug for ib_srpt multi-channel (hch) - Make TFO close_session() and shutdown_session() optional (hch) - Drop se_sess->sess_kref + convert tcm_qla2xxx to internal kref (hch) - Add tcm_qla2xxx endpoint attribute for basic FC jammer (Laurence) - Refactor iscsi-target RX/TX PDU encode/decode into common code (Varun) - Extend iscsit_transport with xmit_pdu, release_cmd, get_rx_pdu, validate_parameters, and get_r2t_ttt for generic ISO offload (Varun) - Initial merge of cxgb iscsi-segment offload target driver (Varun) The bulk of the changes are Chelsio's new driver, along with a number of iscsi-target common code improvements made by Varun + Co along the way" * 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending: (29 commits) iscsi-target: Fix early sk_data_ready LOGIN_FLAGS_READY race cxgbit: Use type ISCSI_CXGBIT + cxgbit tpg_np attribute iscsi-target: Convert transport drivers to signal rdma_shutdown iscsi-target: Make iscsi_tpg_np driver show/store use generic code tcm_qla2xxx Add SCSI command jammer/discard capability iscsi-target: graceful disconnect on invalid mapping to iovec target: need_to_release is always false, remove redundant check and kfree target: remove sess_kref and ->shutdown_session iscsi-target: remove usage of ->shutdown_session tcm_qla2xxx: introduce a private sess_kref target: make close_session optional target: make ->shutdown_session optional target: remove acl_stop target: consolidate and fix session shutdown cxgbit: add files for cxgbit.ko iscsi-target: export symbols iscsi-target: call complete on conn_logout_comp iscsi-target: clear tx_thread_active iscsi-target: add new offload transport type iscsi-target: use conn_transport->transport_type in text rsp ...
2016-05-28Merge tag 'for-linus' of ↵Linus Torvalds105-3400/+1986
git://git.kernel.org/pub/scm/linux/kernel/git/dledford/rdma Pull more rdma updates from Doug Ledford: "This is the second group of code for the 4.7 merge window. It looks large, but only in one sense. I'll get to that in a minute. The list of changes here breaks down as follows: - Dynamic counter infrastructure in the IB drivers This is a sysfs based code to allow free form access to the hardware counters RDMA devices might support so drivers don't need to code this up repeatedly themselves - SendOnlyFullMember multicast support - IB router support - A couple misc fixes - The big item on the list: hfi1 driver updates, plus moving the hfi1 driver out of staging There was a group of 15 patches in the hfi1 list that I thought I had in the first pull request but they weren't. So that added to the length of the hfi1 section here. As far as these go, everything but the hfi1 is pretty straight forward. The hfi1 is, if you recall, the driver that Al had complaints about how it used the write/writev interfaces in an overloaded fashion. The write portion of their interface behaved like the write handler in the IB stack proper and did bi-directional communications. The writev interface, on the other hand, only accepts SDMA request structures. The completions for those structures are sent back via an entirely different event mechanism. With the security patch, we put security checks on the write interface, however, we also knew they would be going away soon. Now, we've converted the write handler in the hfi1 driver to use ioctls from the IB reserved magic area for its bidirectional communications. With that change, Intel has addressed all of the items originally on their TODO when they went into staging (as well as many items added to the list later). As such, I moved them out, and since they were the last item in the staging/rdma directory, and I don't have immediate plans to use the staging area again, I removed the staging/rdma area. Because of the move out of staging, as well as a series of 5 patches in the hfi1 driver that removed code people thought should be done in a different way and was optional to begin with (a snoop debug interface, an eeprom driver for an eeprom connected directory to their hfi1 chip and not via an i2c bus, and a few other things like that), the line count, especially the removal count, is high" * tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dledford/rdma: (56 commits) staging/rdma: Remove the entire rdma subdirectory of staging IB/core: Make device counter infrastructure dynamic IB/hfi1: Fix pio map initialization IB/hfi1: Correct 8051 link parameter settings IB/hfi1: Update pkey table properly after link down or FM start IB/rdamvt: Fix rdmavt s_ack_queue sizing IB/rdmavt: Max atomic value should be a u8 IB/hfi1: Fix hard lockup due to not using save/restore spin lock IB/hfi1: Add tracing support for send with invalidate opcode IB/hfi1, qib: Add ieth to the packet header definitions IB/hfi1: Move driver out of staging IB/hfi1: Do not free hfi1 cdev parent structure early IB/hfi1: Add trace message in user IOCTL handling IB/hfi1: Remove write(), use ioctl() for user cmds IB/hfi1: Add ioctl() interface for user commands IB/hfi1: Remove unused user command IB/hfi1: Remove snoop/diag interface IB/hfi1: Remove EPROM functionality from data device IB/hfi1: Remove UI char device IB/hfi1: Remove multiple device cdev ...
2016-05-28Revert "platform/chrome: chromeos_laptop: Add Leon Touch"Benson Leung1-15/+0
This reverts commit bff3c624dc7261a084a4d25a0b09c3fb0fec872a. Board "Leon" is otherwise known as "Toshiba CB35" and we already have the entry that supports that board as of this commit : 963cb6f platform/chrome: chromeos_laptop - Add Toshiba CB35 Touch Remove this duplicate. Signed-off-by: Benson Leung <bleung@chromium.org> Signed-off-by: Olof Johansson <olof@lixom.net>
2016-05-28i2c: dev: use after free in detachDan Carpenter1-1/+1
The call to put_i2c_dev() frees "i2c_dev" so there is a use after free when we call cdev_del(&i2c_dev->cdev). Fixes: d6760b14d4a1 ('i2c: dev: switch from register_chrdev to cdev API') Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-05-28MIPS: Add missing FROZEN hotplug notifier transitionsAnna-Maria Gleixner1-1/+1
The corresponding FROZEN hotplug notifier transitions used on suspend/resume are ignored. Therefore the switch case action argument is masked with the frozen hotplug notifier transition mask. Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de> Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org Cc: rt@linutronix.de Patchwork: https://patchwork.linux-mips.org/patch/13351/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-28MIPS: Build microMIPS VDSO for microMIPS kernelsJames Hogan1-0/+1
MicroMIPS kernels may be expected to run on microMIPS only cores which don't support the normal MIPS instruction set, so be sure to pass the -mmicromips flag through to the VDSO cflags. Fixes: ebb5e78cc634 ("MIPS: Initial implementation of a VDSO") Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paul Burton <paul.burton@imgtec.com> Cc: linux-mips@linux-mips.org Cc: <stable@vger.kernel.org> # 4.4.x- Patchwork: https://patchwork.linux-mips.org/patch/13349/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-28MIPS: Fix sigreturn via VDSO on microMIPS kernelJames Hogan1-8/+0
In microMIPS kernels, handle_signal() sets the isa16 mode bit in the vdso address so that the sigreturn trampolines (which are offset from the VDSO) get executed as microMIPS. However commit ebb5e78cc634 ("MIPS: Initial implementation of a VDSO") changed the offsets to come from the VDSO image, which already have the isa16 mode bit set correctly since they're extracted from the VDSO shared library symbol table. Drop the isa16 mode bit handling from handle_signal() to fix sigreturn for cores which support both microMIPS and normal MIPS. This doesn't fix microMIPS only cores, since the VDSO is still built for normal MIPS, but thats a separate problem. Fixes: ebb5e78cc634 ("MIPS: Initial implementation of a VDSO") Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paul Burton <paul.burton@imgtec.com> Cc: linux-mips@linux-mips.org Cc: <stable@vger.kernel.org> # 4.4.x- Patchwork: https://patchwork.linux-mips.org/patch/13348/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>