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| * powerpc/mm: Convert pte_user() to static inlineMichael Ellerman2016-05-01
| | | | | | | | | | | | | | | | | | | | | | | | | | | | In a subsequent patch we want to add a second definition of pte_user(). Before we do that, make the signature clear, ie. it takes a pte_t and returns bool. We move it up inside the existing #ifndef __ASSEMBLY__ block, but otherwise it's a straight conversion. Convert the call in settlbcam(), which passes an unsigned long, to pass a pte_t. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * powerpc/mm/subpage: Clear RWX bit to indicate no accessAneesh Kumar K.V2016-05-01
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Subpage protection used to depend on the _PAGE_USER bit to implement no access mode. This patch switches that to use _PAGE_RWX. We clear Read, Write and Execute access from the pte instead of clearing _PAGE_USER now. This was done so that we can switch to _PAGE_PRIVILEGED in a later patch. subpage_protection() returns pte bits that need to be cleared. Instead of updating the interface to handle no-access in a separate way, it appears simpler to clear RWX acecss to indicate no access. We still don't insert hash ptes for no access implied by !_PAGE_RWX. Hence we should not get PROT_FAULT with change. Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * powerpc/mm: Use _PAGE_READ to indicate Read accessAneesh Kumar K.V2016-05-01
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This splits the _PAGE_RW bit into _PAGE_READ and _PAGE_WRITE. It also removes the dependency on _PAGE_USER for implying read only. Few things to note here is that, we have read implied with write and execute permission. Hence we should always find _PAGE_READ set on hash pte fault. We still can't switch PROT_NONE to !(_PAGE_RWX). Auto numa depends on marking a prot none pte _PAGE_WRITE. (For more details look at b191f9b106ea "mm: numa: preserve PTE write permissions across a NUMA hinting fault") Cc: Arnd Bergmann <arnd@arndb.de> Cc: Jeremy Kerr <jk@ozlabs.org> Cc: Frederic Barrat <fbarrat@linux.vnet.ibm.com> Acked-by: Ian Munsie <imunsie@au1.ibm.com> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * powerpc/mm: Use big endian Linux page tables for book3s 64Aneesh Kumar K.V2016-05-01
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Traditionally Power server machines have used the Hashed Page Table MMU mode. In this mode Linux manages its own tree of nested page tables, aka. "the Linux page tables", which are not used by the hardware directly, and software loads translations into the hash page table for use by the hardware. Power ISA 3.0 defines a new MMU mode, known as Radix Tree Translation, where the hardware can directly operate on the Linux page tables. However the hardware requires that the page tables be in big endian format. To accommodate this, switch the pgtable types to __be64 and add appropriate endian conversions. Because we will be supporting a single kernel binary that boots using either radix or hash mode, we always store the Linux page tables big endian, even in hash mode where they are not actually used by the hardware. Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> [mpe: Fix sparse errors, flesh out change log] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * powerpc/mm: Add pte_xchg() helperMichael Ellerman2016-05-01
| | | | | | | | | | | | | | | | | | | | | | | | We have five locations in 64-bit hash MMU code that do a cmpxchg() of a PTE. Currently doing it inline OK, but in a future patch we will be converting the PTEs to __be64 in some configs. In that case we will need casts at every cmpxchg() site in order to keep sparse happy. So move the logic into a helper, this is a reasonably nice cleanup on its own. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * powerpc/mm: Drop PTE_ATOMIC_UPDATES from pmd_hugepage_update()Aneesh Kumar K.V2016-05-01
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | pmd_hugepage_update() is inside #ifdef CONFIG_TRANSPARENT_HUGEPAGE. THP can only be enabled if PPC_BOOK3S_64=y && PPC_64K_PAGES=y, aka. hash64. On hash64 we always define PTE_ATOMIC_UPDATES to 1, meaning the #ifdef in pmd_hugepage_update() is unnecessary, so drop it. That is also the only use of PTE_ATOMIC_UPDATES in any of the hash code, meaning we no longer need to #define it at all in the hash headers. Note it's still #defined and used in the nohash code. Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * powerpc: sparse: Include headers for __weak symbolsDaniel Axtens2016-04-12
| | | | | | | | | | | | | | | | | | | | | | | | Sometimes when sparse warns about undefined symbols, it isn't because they should have 'static' added, it's because they're overriding __weak symbols defined elsewhere, and the header has been missed. Fix a few of them by adding appropriate headers. Signed-off-by: Daniel Axtens <dja@axtens.net> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * powerpc/mm: Remove long disabled SLB codeMichael Ellerman2016-04-11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | We have a bunch of SLB related code in the tree which is there to handle dynamic VSIDs - but currently it's all disabled at compile time. The comments say "Keep that around for when we re-implement dynamic VSIDs". But that was over 10 years ago (commit 3c726f8dee6f ("[PATCH] ppc64: support 64k pages")). The chance that it would still work unchanged is minimal, and in the meantime it's confusing to folks browsing/grepping the code. If we ever want to re-instate it, it's in the git history. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Acked-by: Balbir Singh <bsingharora@gmail.com>
* | powerpc: mm: use hugetlb_bad_size()Vaishali Thakkar2016-05-19
|/ | | | | | | | | | | | | | | | | | | Update setup_hugepagesz() to call hugetlb_bad_size() when unsupported hugepage size is found. Signed-off-by: Vaishali Thakkar <vaishali.thakkar@oracle.com> Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com> Reviewed-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Hillf Danton <hillf.zj@alibaba-inc.com> Cc: Yaowei Bai <baiyaowei@cmss.chinamobile.com> Cc: Dominik Dingel <dingel@linux.vnet.ibm.com> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Paul Gortmaker <paul.gortmaker@windriver.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* powerpc/mm: Fixup preempt underflow with huge pagesSebastian Siewior2016-03-28
| | | | | | | | | | | | | | | | | | | | | | | hugepd_free() used __get_cpu_var() once. Nothing ensured that the code accessing the variable did not migrate from one CPU to another and soon this was noticed by Tiejun Chen in 94b09d755462 ("powerpc/hugetlb: Replace __get_cpu_var with get_cpu_var"). So we had it fixed. Christoph Lameter was doing his __get_cpu_var() replaces and forgot PowerPC. Then he noticed this and sent his fixed up batch again which got applied as 69111bac42f5 ("powerpc: Replace __get_cpu_var uses"). The careful reader will noticed one little detail: get_cpu_var() got replaced with this_cpu_ptr(). So now we have a put_cpu_var() which does a preempt_enable() and nothing that does preempt_disable() so we underflow the preempt counter. Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Christoph Lameter <cl@linux.com> Cc: stable@vger.kernel.org Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* Merge tag 'powerpc-4.6-1' of ↵Linus Torvalds2016-03-19
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc updates from Michael Ellerman: "This was delayed a day or two by some build-breakage on old toolchains which we've now fixed. There's two PCI commits both acked by Bjorn. There's one commit to mm/hugepage.c which is (co)authored by Kirill. Highlights: - Restructure Linux PTE on Book3S/64 to Radix format from Paul Mackerras - Book3s 64 MMU cleanup in preparation for Radix MMU from Aneesh Kumar K.V - Add POWER9 cputable entry from Michael Neuling - FPU/Altivec/VSX save/restore optimisations from Cyril Bur - Add support for new ftrace ABI on ppc64le from Torsten Duwe Various cleanups & minor fixes from: - Adam Buchbinder, Andrew Donnellan, Balbir Singh, Christophe Leroy, Cyril Bur, Luis Henriques, Madhavan Srinivasan, Pan Xinhui, Russell Currey, Sukadev Bhattiprolu, Suraj Jitindar Singh. General: - atomics: Allow architectures to define their own __atomic_op_* helpers from Boqun Feng - Implement atomic{, 64}_*_return_* variants and acquire/release/ relaxed variants for (cmp)xchg from Boqun Feng - Add powernv_defconfig from Jeremy Kerr - Fix BUG_ON() reporting in real mode from Balbir Singh - Add xmon command to dump OPAL msglog from Andrew Donnellan - Add xmon command to dump process/task similar to ps(1) from Douglas Miller - Clean up memory hotplug failure paths from David Gibson pci/eeh: - Redesign SR-IOV on PowerNV to give absolute isolation between VFs from Wei Yang. - EEH Support for SRIOV VFs from Wei Yang and Gavin Shan. - PCI/IOV: Rename and export virtfn_{add, remove} from Wei Yang - PCI: Add pcibios_bus_add_device() weak function from Wei Yang - MAINTAINERS: Update EEH details and maintainership from Russell Currey cxl: - Support added to the CXL driver for running on both bare-metal and hypervisor systems, from Christophe Lombard and Frederic Barrat. - Ignore probes for virtual afu pci devices from Vaibhav Jain perf: - Export Power8 generic and cache events to sysfs from Sukadev Bhattiprolu - hv-24x7: Fix usage with chip events, display change in counter values, display domain indices in sysfs, eliminate domain suffix in event names, from Sukadev Bhattiprolu Freescale: - Updates from Scott: "Highlights include 8xx optimizations, 32-bit checksum optimizations, 86xx consolidation, e5500/e6500 cpu hotplug, more fman and other dt bits, and minor fixes/cleanup" * tag 'powerpc-4.6-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (179 commits) powerpc: Fix unrecoverable SLB miss during restore_math() powerpc/8xx: Fix do_mtspr_cpu6() build on older compilers powerpc/rcpm: Fix build break when SMP=n powerpc/book3e-64: Use hardcoded mttmr opcode powerpc/fsl/dts: Add "jedec,spi-nor" flash compatible powerpc/T104xRDB: add tdm riser card node to device tree powerpc32: PAGE_EXEC required for inittext powerpc/mpc85xx: Add pcsphy nodes to FManV3 device tree powerpc/mpc85xx: Add MDIO bus muxing support to the board device tree(s) powerpc/86xx: Introduce and use common dtsi powerpc/86xx: Update device tree powerpc/86xx: Move dts files to fsl directory powerpc/86xx: Switch to kconfig fragments approach powerpc/86xx: Update defconfigs powerpc/86xx: Consolidate common platform code powerpc32: Remove one insn in mulhdu powerpc32: small optimisation in flush_icache_range() powerpc: Simplify test in __dma_sync() powerpc32: move xxxxx_dcache_range() functions inline powerpc32: Remove clear_pages() and define clear_page() inline ...
| * powerpc32: PAGE_EXEC required for inittextChristophe Leroy2016-03-11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | PAGE_EXEC is required for inittext, otherwise CONFIG_DEBUG_PAGEALLOC ends up with an Oops [ 0.000000] Inode-cache hash table entries: 8192 (order: 1, 32768 bytes) [ 0.000000] Sorting __ex_table... [ 0.000000] bootmem::free_all_bootmem_core nid=0 start=0 end=2000 [ 0.000000] Unable to handle kernel paging request for instruction fetch [ 0.000000] Faulting instruction address: 0xc045b970 [ 0.000000] Oops: Kernel access of bad area, sig: 11 [#1] [ 0.000000] PREEMPT DEBUG_PAGEALLOC CMPC885 [ 0.000000] CPU: 0 PID: 0 Comm: swapper Not tainted 3.18.25-local-dirty #1673 [ 0.000000] task: c04d83d0 ti: c04f8000 task.ti: c04f8000 [ 0.000000] NIP: c045b970 LR: c045b970 CTR: 0000000a [ 0.000000] REGS: c04f9ea0 TRAP: 0400 Not tainted (3.18.25-local-dirty) [ 0.000000] MSR: 08001032 <ME,IR,DR,RI> CR: 39955d35 XER: a000ff40 [ 0.000000] GPR00: c045b970 c04f9f50 c04d83d0 00000000 ffffffff c04dcdf4 00000048 c04f6b10 GPR08: c04f6ab0 00000001 c0563488 c04f6ab0 c04f8000 00000000 00000000 b6db6db7 GPR16: 00003474 00000180 00002000 c7fec000 00000000 000003ff 00000176 c0415014 GPR24: c0471018 c0414ee8 c05304e8 c03aeaac c0510000 c0471018 c0471010 00000000 [ 0.000000] NIP [c045b970] free_all_bootmem+0x164/0x228 [ 0.000000] LR [c045b970] free_all_bootmem+0x164/0x228 [ 0.000000] Call Trace: [ 0.000000] [c04f9f50] [c045b970] free_all_bootmem+0x164/0x228 (unreliable) [ 0.000000] [c04f9fa0] [c0454044] mem_init+0x3c/0xd0 [ 0.000000] [c04f9fb0] [c045080c] start_kernel+0x1f4/0x390 [ 0.000000] [c04f9ff0] [c0002214] start_here+0x38/0x98 [ 0.000000] Instruction dump: [ 0.000000] 2f150000 7f968840 72a90001 3ad60001 56b5f87e 419a0028 419e0024 41a20018 [ 0.000000] 807cc20c 38800000 7c638214 4bffd2f5 <3a940001> 3a100024 4bffffc8 7e368b78 [ 0.000000] ---[ end trace dc8fa200cb88537f ]--- Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Scott Wood <oss@buserror.net>
| * powerpc: Simplify test in __dma_sync()Christophe Leroy2016-03-11
| | | | | | | | | | | | | | | | This simplification helps the compiler. We now have only one test instead of two, so it reduces the number of branches. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Scott Wood <oss@buserror.net>
| * powerpc/8xx: rewrite flush_instruction_cache() in CChristophe Leroy2016-03-11
| | | | | | | | | | | | | | | | | | | | On PPC8xx, flushing instruction cache is performed by writing in register SPRN_IC_CST. This registers suffers CPU6 ERRATA. The patch rewrites the fonction in C so that CPU6 ERRATA will be handled transparently Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Scott Wood <oss@buserror.net>
| * powerpc/8xx: rewrite set_context() in CChristophe Leroy2016-03-11
| | | | | | | | | | | | | | | | | | There is no real need to have set_context() in assembly. Now that we have mtspr() handling CPU6 ERRATA directly, we can rewrite set_context() in C language for easier maintenance. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Scott Wood <oss@buserror.net>
| * powerpc32: remove ioremap_baseChristophe Leroy2016-03-11
| | | | | | | | | | | | | | ioremap_base is not initialised and is nowhere used so remove it Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Scott Wood <oss@buserror.net>
| * powerpc32: Remove useless/wrong MMU:setio progress messageChristophe Leroy2016-03-11
| | | | | | | | | | | | | | | | | | Commit 771168494719 ("[POWERPC] Remove unused machine call outs") removed the call to setup_io_mappings(), so remove the associated progress line message Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Scott Wood <oss@buserror.net>
| * powerpc32: refactor x_mapped_by_bats() and x_mapped_by_tlbcam() togetherChristophe Leroy2016-03-11
| | | | | | | | | | | | | | | | | | | | x_mapped_by_bats() and x_mapped_by_tlbcam() serve the same kind of purpose, and are never defined at the same time. So rename them x_block_mapped() and define them in the relevant places Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Scott Wood <oss@buserror.net>
| * powerpc/8xx: move setup_initial_memory_limit() into 8xx_mmu.cChristophe Leroy2016-03-11
| | | | | | | | | | | | | | | | Now we have a 8xx specific .c file for that so put it in there as other powerpc variants do Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Scott Wood <oss@buserror.net>
| * powerpc/8xx: Map linear kernel RAM with 8M pagesChristophe Leroy2016-03-11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | On a live running system (VoIP gateway for Air Trafic Control), over a 10 minutes period (with 277s idle), we get 87 millions DTLB misses and approximatly 35 secondes are spent in DTLB handler. This represents 5.8% of the overall time and even 10.8% of the non-idle time. Among those 87 millions DTLB misses, 15% are on user addresses and 85% are on kernel addresses. And within the kernel addresses, 93% are on addresses from the linear address space and only 7% are on addresses from the virtual address space. MPC8xx has no BATs but it has 8Mb page size. This patch implements mapping of kernel RAM using 8Mb pages, on the same model as what is done on the 40x. In 4k pages mode, each PGD entry maps a 4Mb area: we map every two entries to the same 8Mb physical page. In each second entry, we add 4Mb to the page physical address to ease life of the FixupDAR routine. This is just ignored by HW. In 16k pages mode, each PGD entry maps a 64Mb area: each PGD entry will point to the first page of the area. The DTLB handler adds the 3 bits from EPN to map the correct page. With this patch applied, we now get only 13 millions TLB misses during the 10 minutes period. The idle time has increased to 313s and the overall time spent in DTLB miss handler is 6.3s, which represents 1% of the overall time and 2.2% of non-idle time. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Scott Wood <oss@buserror.net>
| * powerpc/mm: any thread in one core can be the first to setup TLB1chenhui zhao2016-03-05
| | | | | | | | | | | | | | | | | | | | | | On e6500, in the case of cpu hotplug, either thread in one core may be the first thread initilzing the TLB1. The subsequent threads must not setup it again. The code is derived from the comment of Scott Wood. Signed-off-by: Chenhui Zhao <chenhui.zhao@freescale.com> Signed-off-by: Scott Wood <oss@buserror.net>
| * powerpc/mm: add _PAGE_HASHPTE similar to 4K hashAneesh Kumar K.V2016-03-03
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We don't need to update linux page table entry with _PAGE_HASHPTE early in hash pte fault. A parallel pte update will loop via _PAGE_BUSY and look at _PAGE_HASHPTE for a required hpte flush only if _PAGE_BUSY is cleared. That ensures a pte update will wait for a parallel hpte insert to finish before looking at _PAGE_HASHPTE bit. To avoid further confusion drop setting _PAGE_HASHPTE in cmpxchg in __hash_page_4K. commit 41743a4e34f0 ("powerpc: Free a PTE bit on ppc64 with 64K pages") did similar change for 64K config Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * powerp/mm: Update code commentsAneesh Kumar K.V2016-03-03
| | | | | | | | | | | | | | We are updating pte in those functions. Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * mm: Some arch may want to use HPAGE_PMD related values as variablesKirill A. Shutemov2016-03-03
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | With next generation power processor, we are having a new mmu model [1] that require us to maintain a different linux page table format. Inorder to support both current and future ppc64 systems with a single kernel we need to make sure kernel can select between different page table format at runtime. With the new MMU (radix MMU) added, we will have two different pmd hugepage size 16MB for hash model and 2MB for Radix model. Hence make HPAGE_PMD related values as a variable. Actual conversion of HPAGE_PMD to a variable for ppc64 happens in a followup patch. [1] http://ibm.biz/power-isa3 (Needs registration). Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * powerpc/mm: Switch book3s 64 with 64K page size to 4 level page tableAneesh Kumar K.V2016-03-03
| | | | | | | | | | | | | | | | | | | | | | | | This is needed so that we can support both hash and radix page table using single kernel. Radix kernel uses a 4 level table. We now use physical address in upper page table tree levels. Even though they are aligned to their size, for the masked bits we use the bit positions as per PowerISA 3.0. Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * powerpc/mm: Split hash page table sizing heuristic into a helperDavid Gibson2016-03-01
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | htab_get_table_size() either retrieve the size of the hash page table (HPT) from the device tree - if the HPT size is determined by firmware - or uses a heuristic to determine a good size based on RAM size if the kernel is responsible for allocating the HPT. To support a PAPR extension allowing resizing of the HPT, we're going to want the memory size -> HPT size logic elsewhere, so split it out into a helper function. Signed-off-by: David Gibson <david@gibson.dropbear.id.au> Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * powerpc/mm: Clean up memory hotplug failure pathsDavid Gibson2016-03-01
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This makes a number of cleanups to handling of mapping failures during memory hotplug on Power: For errors creating the linear mapping for the hot-added region: * This is now reported with EFAULT which is more appropriate than the previous EINVAL (the failure is unlikely to be related to the function's parameters) * An error in this path now prints a warning message, rather than just silently failing to add the extra memory. * Previously a failure here could result in the region being partially mapped. We now clean up any partial mapping before failing. For errors creating the vmemmap for the hot-added region: * This is now reported with EFAULT instead of causing a BUG() - this could happen for external reason (e.g. full hash table) so it's better to handle this non-fatally * An error message is also printed, so the failure won't be silent * As above a failure could cause a partially mapped region, we now clean this up. [mpe: move htab_remove_mapping() out of #ifdef CONFIG_MEMORY_HOTPLUG to enable this] Signed-off-by: David Gibson <david@gibson.dropbear.id.au> Reviewed-by: Paul Mackerras <paulus@samba.org> Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * powerpc/mm: Handle removing maybe-present bolted HPTEsDavid Gibson2016-03-01
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | At the moment the hpte_removebolted callback in ppc_md returns void and will BUG_ON() if the hpte it's asked to remove doesn't exist in the first place. This is awkward for the case of cleaning up a mapping which was partially made before failing. So, we add a return value to hpte_removebolted, and have it return ENOENT in the case that the HPTE to remove didn't exist in the first place. In the (sole) caller, we propagate errors in hpte_removebolted to its caller to handle. However, we handle ENOENT specially, continuing to complete the unmapping over the specified range before returning the error to the caller. This means that htab_remove_mapping() will work sanely on a partially present mapping, removing any HPTEs which are present, while also returning ENOENT to its caller in case it's important there. There are two callers of htab_remove_mapping(): - In remove_section_mapping() we already WARN_ON() any error return, which is reasonable - in this case the mapping should be fully present - In vmemmap_remove_mapping() we BUG_ON() any error. We change that to just a WARN_ON() in the case of ENOENT, since failing to remove a mapping that wasn't there in the first place probably shouldn't be fatal. Signed-off-by: David Gibson <david@gibson.dropbear.id.au> Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * powerpc/mm: Clean up error handling for htab_remove_mappingDavid Gibson2016-03-01
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently, the only error that htab_remove_mapping() can report is -EINVAL, if removal of bolted HPTEs isn't implemeted for this platform. We make a few clean ups to the handling of this: * EINVAL isn't really the right code - there's nothing wrong with the function's arguments - use ENODEV instead * We were also printing a warning message, but that's a decision better left up to the callers, so remove it * One caller is vmemmap_remove_mapping(), which will just BUG_ON() on error, making the warning message redundant, so no change is needed there. * The other caller is remove_section_mapping(). This is called in the memory hot remove path at a point after vmemmap_remove_mapping() so if hpte_removebolted isn't implemented, we'd expect to have already BUG()ed anyway. Put a WARN_ON() here, in lieu of a printk() since this really shouldn't be happening. Signed-off-by: David Gibson <david@gibson.dropbear.id.au> Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * powerpc: Fix misspellings in comments.Adam Buchbinder2016-03-01
| | | | | | | | | | Signed-off-by: Adam Buchbinder <adam.buchbinder@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * powerpc/mm/book3s-64: Move HPTE-related bits in PTE to upper endPaul Mackerras2016-02-29
| | | | | | | | | | | | | | | | | | | | | | | | | | | | This moves the _PAGE_HASHPTE, _PAGE_F_GIX and _PAGE_F_SECOND fields in the Linux PTE on 64-bit Book 3S systems to the most significant byte. Of the 5 bits, one is a software-use bit and the other four are reserved bit positions in the PowerISA v3.0 radix PTE format. Using these bits is OK because these bits are all to do with tracking the HPTE(s) associated with the Linux PTE, and therefore won't be needed in radix mode. This frees up bit positions in the lower two bytes. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * powerpc/mm/book3s-64: Move _PAGE_PRESENT to the most significant bitPaul Mackerras2016-02-29
| | | | | | | | | | | | | | | | | | This changes _PAGE_PRESENT for 64-bit Book 3S processors from 0x2 to 0x8000_0000_0000_0000, because that is where PowerISA v3.0 CPUs in radix mode will expect to find it. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * powerpc/mm/book3s-64: Use physical addresses in upper page table tree levelsPaul Mackerras2016-02-29
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This changes the Linux page tables to store physical addresses rather than kernel virtual addresses in the upper levels of the tree (pgd, pud and pmd) for 64-bit Book 3S machines. This also changes the hugepd pointers used to implement hugepages when the base page size is 4k to store physical addresses rather than virtual addresses (again just for 64-bit Book3S machines). This frees up some high order bits, and will be needed with PowerISA v3.0 machines which read the page table tree in hardware in radix mode. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * powerpc/mm/book3s-64: Free up 7 high-order bits in the Linux PTEPaul Mackerras2016-02-27
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This frees up bits 57-63 in the Linux PTE on 64-bit Book 3S machines. In the 4k page case, this is done just by reducing the size of the RPN field to 39 bits, giving 51-bit real addresses. In the 64k page case, we had 10 unused bits in the middle of the PTE, so this moves the RPN field down 10 bits to make use of those unused bits. This means the RPN field is now 3 bits larger at 37 bits, giving 53-bit real addresses in the normal case, or 49-bit real addresses for the special 4k PFN case. We are doing this in order to be able to move some other PTE bits into the positions where PowerISA V3.0 processors will expect to find them in radix-tree mode. Ultimately we will be able to move the RPN field to lower bit positions and make it larger. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * powerpc/mm/book3s-64: Clean up some obsolete or misleading commentsPaul Mackerras2016-02-27
| | | | | | | | | | | | | | No code changes. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* | mm: introduce page reference manipulation functionsJoonsoo Kim2016-03-17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The success of CMA allocation largely depends on the success of migration and key factor of it is page reference count. Until now, page reference is manipulated by direct calling atomic functions so we cannot follow up who and where manipulate it. Then, it is hard to find actual reason of CMA allocation failure. CMA allocation should be guaranteed to succeed so finding offending place is really important. In this patch, call sites where page reference is manipulated are converted to introduced wrapper function. This is preparation step to add tracepoint to each page reference manipulation function. With this facility, we can easily find reason of CMA allocation failure. There is no functional change in this patch. In addition, this patch also converts reference read sites. It will help a second step that renames page._count to something else and prevents later attempt to direct access to it (Suggested by Andrew). Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> Acked-by: Michal Nazarewicz <mina86@mina86.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Minchan Kim <minchan@kernel.org> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | powerpc: query dynamic DEBUG_PAGEALLOC settingJoonsoo Kim2016-03-17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | We can disable debug_pagealloc processing even if the code is compiled with CONFIG_DEBUG_PAGEALLOC. This patch changes the code to query whether it is enabled or not in runtime. Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> Acked-by: David Rientjes <rientjes@google.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Christoph Lameter <cl@linux.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds2016-03-16
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull KVM updates from Paolo Bonzini: "One of the largest releases for KVM... Hardly any generic changes, but lots of architecture-specific updates. ARM: - VHE support so that we can run the kernel at EL2 on ARMv8.1 systems - PMU support for guests - 32bit world switch rewritten in C - various optimizations to the vgic save/restore code. PPC: - enabled KVM-VFIO integration ("VFIO device") - optimizations to speed up IPIs between vcpus - in-kernel handling of IOMMU hypercalls - support for dynamic DMA windows (DDW). s390: - provide the floating point registers via sync regs; - separated instruction vs. data accesses - dirty log improvements for huge guests - bugfixes and documentation improvements. x86: - Hyper-V VMBus hypercall userspace exit - alternative implementation of lowest-priority interrupts using vector hashing (for better VT-d posted interrupt support) - fixed guest debugging with nested virtualizations - improved interrupt tracking in the in-kernel IOAPIC - generic infrastructure for tracking writes to guest memory - currently its only use is to speedup the legacy shadow paging (pre-EPT) case, but in the future it will be used for virtual GPUs as well - much cleanup (LAPIC, kvmclock, MMU, PIT), including ubsan fixes" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (217 commits) KVM: x86: remove eager_fpu field of struct kvm_vcpu_arch KVM: x86: disable MPX if host did not enable MPX XSAVE features arm64: KVM: vgic-v3: Only wipe LRs on vcpu exit arm64: KVM: vgic-v3: Reset LRs at boot time arm64: KVM: vgic-v3: Do not save an LR known to be empty arm64: KVM: vgic-v3: Save maintenance interrupt state only if required arm64: KVM: vgic-v3: Avoid accessing ICH registers KVM: arm/arm64: vgic-v2: Make GICD_SGIR quicker to hit KVM: arm/arm64: vgic-v2: Only wipe LRs on vcpu exit KVM: arm/arm64: vgic-v2: Reset LRs at boot time KVM: arm/arm64: vgic-v2: Do not save an LR known to be empty KVM: arm/arm64: vgic-v2: Move GICH_ELRSR saving to its own function KVM: arm/arm64: vgic-v2: Save maintenance interrupt state only if required KVM: arm/arm64: vgic-v2: Avoid accessing GICH registers KVM: s390: allocate only one DMA page per VM KVM: s390: enable STFLE interpretation only if enabled for the guest KVM: s390: wake up when the VCPU cpu timer expires KVM: s390: step the VCPU timer while in enabled wait KVM: s390: protect VCPU cpu timer with a seqcount KVM: s390: step VCPU cpu timer during kvm_run ioctl ...
| * \ Merge tag 'kvm-arm-for-4.6' of ↵Paolo Bonzini2016-03-09
| |\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD KVM/ARM updates for 4.6 - VHE support so that we can run the kernel at EL2 on ARMv8.1 systems - PMU support for guests - 32bit world switch rewritten in C - Various optimizations to the vgic save/restore code Conflicts: include/uapi/linux/kvm.h
| * | | powerpc: Make vmalloc_to_phys() publicAlexey Kardashevskiy2016-02-15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This makes vmalloc_to_phys() public as there will be another user (KVM in-kernel VFIO acceleration) for it soon. As this new user can be compiled as a module, this exports the symbol. As a little optimization, this changes the helper to call vmalloc_to_pfn() instead of vmalloc_to_page() as the size of the struct page may not be power-of-two aligned which will make gcc use multiply instructions instead of shifts. Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> Acked-by: Michael Ellerman <mpe@ellerman.id.au> Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Paul Mackerras <paulus@samba.org>
* | | | Merge branch 'core-resources-for-linus' of ↵Linus Torvalds2016-03-14
|\ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull ram resource handling changes from Ingo Molnar: "Core kernel resource handling changes to support NVDIMM error injection. This tree introduces a new I/O resource type, IORESOURCE_SYSTEM_RAM, for System RAM while keeping the current IORESOURCE_MEM type bit set for all memory-mapped ranges (including System RAM) for backward compatibility. With this resource flag it no longer takes a strcmp() loop through the resource tree to find "System RAM" resources. The new resource type is then used to extend ACPI/APEI error injection facility to also support NVDIMM" * 'core-resources-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: ACPI/EINJ: Allow memory error injection to NVDIMM resource: Kill walk_iomem_res() x86/kexec: Remove walk_iomem_res() call with GART type x86, kexec, nvdimm: Use walk_iomem_res_desc() for iomem search resource: Add walk_iomem_res_desc() memremap: Change region_intersects() to take @flags and @desc arm/samsung: Change s3c_pm_run_res() to use System RAM type resource: Change walk_system_ram() to use System RAM type drivers: Initialize resource entry to zero xen, mm: Set IORESOURCE_SYSTEM_RAM to System RAM kexec: Set IORESOURCE_SYSTEM_RAM for System RAM arch: Set IORESOURCE_SYSTEM_RAM flag for System RAM ia64: Set System RAM type and descriptor x86/e820: Set System RAM type and descriptor resource: Add I/O resource descriptor resource: Handle resource flags properly resource: Add System RAM resource type
| * \ \ \ Merge tag 'v4.5-rc6' into core/resources, to resolve conflictIngo Molnar2016-03-04
| |\ \ \ \ | | | |/ / | | |/| | | | | | | Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | | arch: Set IORESOURCE_SYSTEM_RAM flag for System RAMToshi Kani2016-01-30
| | |/ / | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Set IORESOURCE_SYSTEM_RAM in flags of resource ranges with "System RAM", "Kernel code", "Kernel data", and "Kernel bss". Note that: - IORESOURCE_SYSRAM (i.e. modifier bit) is set in flags when IORESOURCE_MEM is already set. IORESOURCE_SYSTEM_RAM is defined as (IORESOURCE_MEM|IORESOURCE_SYSRAM). - Some archs do not set 'flags' for children nodes, such as "Kernel code". This patch does not change 'flags' in this case. Signed-off-by: Toshi Kani <toshi.kani@hpe.com> Signed-off-by: Borislav Petkov <bp@suse.de> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Luis R. Rodriguez <mcgrof@suse.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Toshi Kani <toshi.kani@hp.com> Cc: linux-arch@vger.kernel.org Cc: linux-arm-kernel@lists.infradead.org Cc: linux-mips@linux-mips.org Cc: linux-mm <linux-mm@kvack.org> Cc: linux-parisc@vger.kernel.org Cc: linux-s390@vger.kernel.org Cc: linux-sh@vger.kernel.org Cc: linuxppc-dev@lists.ozlabs.org Cc: sparclinux@vger.kernel.org Link: http://lkml.kernel.org/r/1453841853-11383-7-git-send-email-bp@alien8.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | | | Merge tag 'powerpc-4.5-5' of ↵Linus Torvalds2016-03-06
|\ \ \ \ | |_|/ / |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc fixes from Michael Ellerman: - cxl: Fix PSL timebase synchronization detection from Frederic Barrat - Fix oops when destroying hw_breakpoint event from Ravi Bangoria - Avoid lbarx on e5500 from Scott Wood * tag 'powerpc-4.5-5' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: powerpc/fsl-book3e: Avoid lbarx on e5500 powerpc/hw_breakpoint: Fix oops when destroying hw_breakpoint event cxl: Fix PSL timebase synchronization detection
| * | | powerpc/fsl-book3e: Avoid lbarx on e5500Scott Wood2016-03-04
| | |/ | |/| | | | | | | | | | | | | | | | | | | | | | | | | lbarx/stbcx. are implemented on e6500, but not on e5500. Likewise, SMT is on e6500, but not on e5500. So, avoid executing an unimplemented instruction by only locking when needed (i.e. in the presence of SMT). Signed-off-by: Scott Wood <oss@buserror.net>
* / | mm: ASLR: use get_random_long()Daniel Cashman2016-02-27
|/ / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Replace calls to get_random_int() followed by a cast to (unsigned long) with calls to get_random_long(). Also address shifting bug which, in case of x86 removed entropy mask for mmap_rnd_bits values > 31 bits. Signed-off-by: Daniel Cashman <dcashman@android.com> Acked-by: Kees Cook <keescook@chromium.org> Cc: "Theodore Ts'o" <tytso@mit.edu> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: David S. Miller <davem@davemloft.net> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Nick Kralevich <nnk@google.com> Cc: Jeff Vander Stoep <jeffv@google.com> Cc: Mark Salyzyn <salyzyn@android.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | powerpc/mm/hash: Clear the invalid slot information correctlyAneesh Kumar K.V2016-02-22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We can get a hash pte fault with 4k base page size and find the pte already inserted with 64K base page size. In that case we need to clear the existing slot information from the old pte. Fix this correctly With THP, we also clear the slot information with respect to all the 64K hash pte mapping that 16MB page. They are all invalid now. This make sure we don't find the slot valid when we fault with 4k base page size. Finding the slot valid should not result in any wrong behavior because we do check again in hash page table for the validity. But we can avoid that check completely. Fixes: a43c0eb8364c022 ("powerpc/mm: Convert 4k hash insert to C") Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* | powerpc/mm: Fix Multi hit ERAT cause by recent THP updateAneesh Kumar K.V2016-02-15
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | With ppc64 we use the deposited pgtable_t to store the hash pte slot information. We should not withdraw the deposited pgtable_t without marking the pmd none. This ensure that low level hash fault handling will skip this huge pte and we will handle them at upper levels. Recent change to pmd splitting changed the above in order to handle the race between pmd split and exit_mmap. The race is explained below. Consider following race: CPU0 CPU1 shrink_page_list() add_to_swap() split_huge_page_to_list() __split_huge_pmd_locked() pmdp_huge_clear_flush_notify() // pmd_none() == true exit_mmap() unmap_vmas() zap_pmd_range() // no action on pmd since pmd_none() == true pmd_populate() As result the THP will not be freed. The leak is detected by check_mm(): BUG: Bad rss-counter state mm:ffff880058d2e580 idx:1 val:512 The above required us to not mark pmd none during a pmd split. The fix for ppc is to clear the huge pte of _PAGE_USER, so that low level fault handling code skip this pte. At higher level we do take ptl lock. That should serialze us against the pmd split. Once the lock is acquired we do check the pmd again using pmd_same. That should always return false for us and hence we should retry the access. We do the pmd_same check in all case after taking plt with THP (do_huge_pmd_wp_page, do_huge_pmd_numa_page and huge_pmd_set_accessed) Also make sure we wait for irq disable section in other cpus to finish before flipping a huge pte entry with a regular pmd entry. Code paths like find_linux_pte_or_hugepte depend on irq disable to get a stable pte_t pointer. A parallel thp split need to make sure we don't convert a pmd pte to a regular pmd entry without waiting for the irq disable section to finish. Fixes: eef1b3ba053a ("thp: implement split_huge_pmd()") Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* powerpc/mm: Allow user space to map rtas_rmo_bufVasant Hegde2016-01-25
| | | | | | | | | | | | | | | | With commit 90a545e9 (restrict /dev/mem to idle io memory ranges) mapping rtas_rmo_buf from user space is failing. Hence we are not able to make RTAS syscall. This patch calls page_is_rtas_user_buf before calling iomem_is_exclusive in devmem_is_allowed(). This will allow user space to map rtas_rmo_buf and we are able to make RTAS syscall. Reported-by: Bharata B Rao <bharata@linux.vnet.ibm.com> CC: Nathan Fontenot <nfont@linux.vnet.ibm.com> Signed-off-by: Vasant Hegde <hegdevasant@linux.vnet.ibm.com> Acked-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* powerpc, thp: remove infrastructure for handling splitting PMDsKirill A. Shutemov2016-01-15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | With new refcounting we don't need to mark PMDs splitting. Let's drop code to handle this. pmdp_splitting_flush() is not needed too: on splitting PMD we will do pmdp_clear_flush() + set_pte_at(). pmdp_clear_flush() will do IPI as needed for fast_gup. Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Tested-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Cc: Sasha Levin <sasha.levin@oracle.com> Cc: Jerome Marchand <jmarchan@redhat.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Hugh Dickins <hughd@google.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Rik van Riel <riel@redhat.com> Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Cc: Steve Capper <steve.capper@linaro.org> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Christoph Lameter <cl@linux.com> Cc: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>