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2024-07-12powerpc/mm: remove hugepd leftoversChristophe Leroy
All targets have now opted out of CONFIG_ARCH_HAS_HUGEPD so remove left over code. Link: https://lkml.kernel.org/r/39c0d0adee6790fc42cee9f458e05fb95136c3dd.1719928057.git.christophe.leroy@csgroup.eu Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Acked-by: Oscar Salvador <osalvador@suse.de> Cc: Jason Gunthorpe <jgg@nvidia.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Peter Xu <peterx@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-07-12powerpc/64s: use contiguous PMD/PUD instead of HUGEPDChristophe Leroy
On book3s/64, the only user of hugepd is hash in 4k mode. All other setups (hash-64, radix-4, radix-64) use leaf PMD/PUD. Rework hash-4k to use contiguous PMD and PUD instead. In that setup there are only two huge page sizes: 16M and 16G. 16M sits at PMD level and 16G at PUD level. pte_update doesn't know page size, lets use the same trick as hpte_need_flush() to get page size from segment properties. That's not the most efficient way but let's do that until callers of pte_update() provide page size instead of just a huge flag. Link: https://lkml.kernel.org/r/7448f60a9b3efd396595f4f735d1e0babc5ae379.1719928057.git.christophe.leroy@csgroup.eu Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc) Cc: Jason Gunthorpe <jgg@nvidia.com> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Oscar Salvador <osalvador@suse.de> Cc: Peter Xu <peterx@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-07-12powerpc/e500: use contiguous PMD instead of hugepdChristophe Leroy
e500 supports many page sizes among which the following size are implemented in the kernel at the time being: 4M, 16M, 64M, 256M, 1G. On e500, TLB miss for hugepages is exclusively handled by SW even on e6500 which has HW assistance for 4k pages, so there are no constraints like on the 8xx. On e500/32, all are at PGD/PMD level and can be handled as cont-PMD. On e500/64, smaller ones are on PMD while bigger ones are on PUD. Again, they can easily be handled as cont-PMD and cont-PUD instead of hugepd. On e500/32, use the pagesize bits in PTE to know if it is a PMD or a leaf entry. This works because the pagesize bits are in the last 12 bits and page tables are 4k aligned. On e500/64, use highest bit which is always 1 on PxD (Because PxD contains virtual address of a kernel memory) and always 0 on PTEs because not all bits of RPN are used/possible. Link: https://lkml.kernel.org/r/dd085987816ed2a0c70adb7e34966cb833fc03e1.1719928057.git.christophe.leroy@csgroup.eu Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: Jason Gunthorpe <jgg@nvidia.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Oscar Salvador <osalvador@suse.de> Cc: Peter Xu <peterx@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-07-12powerpc/8xx: rework support for 8M pages using contiguous PTE entriesChristophe Leroy
In order to fit better with standard Linux page tables layout, add support for 8M pages using contiguous PTE entries in a standard page table. Page tables will then be populated with 1024 similar entries and two PMD entries will point to that page table. The PMD entries also get a flag to tell it is addressing an 8M page, this is required for the HW tablewalk assistance. Link: https://lkml.kernel.org/r/8693d9a0408371043ca63bf9e4a9c140667af63e.1719928057.git.christophe.leroy@csgroup.eu Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Reviewed-by: Oscar Salvador <osalvador@suse.de> Cc: Jason Gunthorpe <jgg@nvidia.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Peter Xu <peterx@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-07-12powerpc/mm: allow hugepages without hugepdChristophe Leroy
In preparation of implementing huge pages on powerpc 8xx without hugepd, enclose hugepd related code inside an ifdef CONFIG_ARCH_HAS_HUGEPD This also allows removing some stubs. Link: https://lkml.kernel.org/r/ada097ca8a4fa85a77f51719516ef2478800d77a.1719928057.git.christophe.leroy@csgroup.eu Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Reviewed-by: Oscar Salvador <osalvador@suse.de> Cc: Jason Gunthorpe <jgg@nvidia.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Peter Xu <peterx@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-03-06hugetlb: parallelize 1G hugetlb initializationGang Li
Optimizing the initialization speed of 1G huge pages through parallelization. 1G hugetlbs are allocated from bootmem, a process that is already very fast and does not currently require optimization. Therefore, we focus on parallelizing only the initialization phase in `gather_bootmem_prealloc`. Here are some test results: test case no patch(ms) patched(ms) saved ------------------- -------------- ------------- -------- 256c2T(4 node) 1G 4745 2024 57.34% 128c1T(2 node) 1G 3358 1712 49.02% 12T 1G 77000 18300 76.23% [akpm@linux-foundation.org: s/initialied/initialized/, per Alexey] Link: https://lkml.kernel.org/r/20240222140422.393911-9-gang.li@linux.dev Signed-off-by: Gang Li <ligang.bdlg@bytedance.com> Tested-by: David Rientjes <rientjes@google.com> Reviewed-by: Muchun Song <muchun.song@linux.dev> Cc: Alexey Dobriyan <adobriyan@gmail.com> Cc: Daniel Jordan <daniel.m.jordan@oracle.com> Cc: David Hildenbrand <david@redhat.com> Cc: Jane Chu <jane.chu@oracle.com> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Paul E. McKenney <paulmck@kernel.org> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: Steffen Klassert <steffen.klassert@secunet.com> Cc: Tim Chen <tim.c.chen@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-02-22mm/hugetlb: move page order check inside hugetlb_cma_reserve()Anshuman Khandual
All platforms could benefit from page order check against MAX_PAGE_ORDER before allocating a CMA area for gigantic hugetlb pages. Let's move this check from individual platforms to generic hugetlb. Link: https://lkml.kernel.org/r/20240209054221.1403364-1-anshuman.khandual@arm.com Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com> Reviewed-by: Jane Chu <jane.chu@oracle.com> Reviewed-by: David Hildenbrand <david@redhat.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will@kernel.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-01-08mm, treewide: rename MAX_ORDER to MAX_PAGE_ORDERKirill A. Shutemov
commit 23baf831a32c ("mm, treewide: redefine MAX_ORDER sanely") has changed the definition of MAX_ORDER to be inclusive. This has caused issues with code that was not yet upstream and depended on the previous definition. To draw attention to the altered meaning of the define, rename MAX_ORDER to MAX_PAGE_ORDER. Link: https://lkml.kernel.org/r/20231228144704.14033-2-kirill.shutemov@linux.intel.com Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-06-19powerpc/hugetlb: pte_alloc_huge()Hugh Dickins
pte_alloc_map() expects to be followed by pte_unmap(), but hugetlb omits that: to keep balance in future, use the recently added pte_alloc_huge() instead. huge_pte_offset() is using __find_linux_pte(), which is using pte_offset_kernel() - don't rename that to _huge, it's more complicated. Link: https://lkml.kernel.org/r/36b4e5d-954b-8569-4fe2-bd1797362441@google.com Signed-off-by: Hugh Dickins <hughd@google.com> Cc: Alexander Gordeev <agordeev@linux.ibm.com> Cc: Alexandre Ghiti <alexghiti@rivosinc.com> Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Christian Borntraeger <borntraeger@linux.ibm.com> Cc: Chris Zankel <chris@zankel.net> Cc: Claudio Imbrenda <imbrenda@linux.ibm.com> Cc: David Hildenbrand <david@redhat.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Greg Ungerer <gerg@linux-m68k.org> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Helge Deller <deller@gmx.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: John David Anglin <dave.anglin@bell.net> Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Max Filippov <jcmvbkbc@gmail.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Michal Simek <monstr@monstr.eu> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Mike Rapoport (IBM) <rppt@kernel.org> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Qi Zheng <zhengqi.arch@bytedance.com> Cc: Russell King <linux@armlinux.org.uk> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-04-05mm, treewide: redefine MAX_ORDER sanelyKirill A. Shutemov
MAX_ORDER currently defined as number of orders page allocator supports: user can ask buddy allocator for page order between 0 and MAX_ORDER-1. This definition is counter-intuitive and lead to number of bugs all over the kernel. Change the definition of MAX_ORDER to be inclusive: the range of orders user can ask from buddy allocator is 0..MAX_ORDER now. [kirill@shutemov.name: fix min() warning] Link: https://lkml.kernel.org/r/20230315153800.32wib3n5rickolvh@box [akpm@linux-foundation.org: fix another min_t warning] [kirill@shutemov.name: fixups per Zi Yan] Link: https://lkml.kernel.org/r/20230316232144.b7ic4cif4kjiabws@box.shutemov.name [akpm@linux-foundation.org: fix underlining in docs] Link: https://lore.kernel.org/oe-kbuild-all/202303191025.VRCTk6mP-lkp@intel.com/ Link: https://lkml.kernel.org/r/20230315113133.11326-11-kirill.shutemov@linux.intel.com Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Reviewed-by: Michael Ellerman <mpe@ellerman.id.au> [powerpc] Cc: "Kirill A. Shutemov" <kirill@shutemov.name> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-11-08hugetlb: simplify hugetlb handling in follow_page_maskMike Kravetz
During discussions of this series [1], it was suggested that hugetlb handling code in follow_page_mask could be simplified. At the beginning of follow_page_mask, there currently is a call to follow_huge_addr which 'may' handle hugetlb pages. ia64 is the only architecture which provides a follow_huge_addr routine that does not return error. Instead, at each level of the page table a check is made for a hugetlb entry. If a hugetlb entry is found, a call to a routine associated with that entry is made. Currently, there are two checks for hugetlb entries at each page table level. The first check is of the form: if (p?d_huge()) page = follow_huge_p?d(); the second check is of the form: if (is_hugepd()) page = follow_huge_pd(). We can replace these checks, as well as the special handling routines such as follow_huge_p?d() and follow_huge_pd() with a single routine to handle hugetlb vmas. A new routine hugetlb_follow_page_mask is called for hugetlb vmas at the beginning of follow_page_mask. hugetlb_follow_page_mask will use the existing routine huge_pte_offset to walk page tables looking for hugetlb entries. huge_pte_offset can be overwritten by architectures, and already handles special cases such as hugepd entries. [1] https://lore.kernel.org/linux-mm/cover.1661240170.git.baolin.wang@linux.alibaba.com/ [mike.kravetz@oracle.com: remove vma (pmd sharing) per Peter] Link: https://lkml.kernel.org/r/20221028181108.119432-1-mike.kravetz@oracle.com [mike.kravetz@oracle.com: remove left over hugetlb_vma_unlock_read()] Link: https://lkml.kernel.org/r/20221030225825.40872-1-mike.kravetz@oracle.com Link: https://lkml.kernel.org/r/20220919021348.22151-1-mike.kravetz@oracle.com Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com> Suggested-by: David Hildenbrand <david@redhat.com> Reviewed-by: David Hildenbrand <david@redhat.com> Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com> Tested-by: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Cc: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Muchun Song <songmuchun@bytedance.com> Cc: Naoya Horiguchi <naoya.horiguchi@linux.dev> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-09-30powerpc/mm: Fix UBSAN warning reported on hugetlbAneesh Kumar K.V
Powerpc architecture supports 16GB hugetlb pages with hash translation. For 4K page size, this is implemented as a hugepage directory entry at PGD level and for 64K it is implemented as a huge page pte at PUD level With 16GB hugetlb size, offset within a page is greater than 32 bits. Hence switch to use unsigned long type when using hugepd_shift. In order to keep things simpler, we make sure we always use unsigned long type when using hugepd_shift() even though all the hugetlb page size won't require that. The hugetlb_free_p*d_range changes are all related to nohash usage where we can have multiple pgd entries pointing to the same hugepd entries. Hence on book3s64 where we can have > 4GB hugetlb page size we will always find more < next even if we compute the value of more correctly. Hence there is no functional change in this patch except that it fixes the below warning. UBSAN: shift-out-of-bounds in arch/powerpc/mm/hugetlbpage.c:499:21 shift exponent 34 is too large for 32-bit type 'int' CPU: 39 PID: 1673 Comm: a.out Not tainted 6.0.0-rc2-00327-gee88a56e8517-dirty #1 Call Trace: dump_stack_lvl+0x98/0xe0 (unreliable) ubsan_epilogue+0x18/0x70 __ubsan_handle_shift_out_of_bounds+0x1bc/0x390 hugetlb_free_pgd_range+0x5d8/0x600 free_pgtables+0x114/0x290 exit_mmap+0x150/0x550 mmput+0xcc/0x210 do_exit+0x420/0xdd0 do_group_exit+0x4c/0xd0 sys_exit_group+0x24/0x30 system_call_exception+0x250/0x600 system_call_common+0xec/0x250 Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> [mpe: Drop generic change to be sent separately, change 1ULL to 1UL] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20220908072440.258301-1-aneesh.kumar@linux.ibm.com
2022-09-26powerpc: Remove CONFIG_PPC_FSL_BOOK3EChristophe Leroy
CONFIG_PPC_FSL_BOOK3E is redundant with CONFIG_PPC_E500. Remove it. And rename five files accordingly. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> [mpe: Rename include guards to match new file names] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/795cb93b88c9a0279289712e674f39e3b108a1b4.1663606876.git.christophe.leroy@csgroup.eu
2022-06-29powerpc: Include asm/firmware.h in all users of firmware_has_feature()Christophe Leroy
Trying to remove asm/ppc_asm.h from all places that don't need it leads to several failures linked to firmware_has_feature(). To fix it, include asm/firmware.h in all files using firmware_has_feature() All users found with: git grep -L "firmware\.h" ` git grep -l "firmware_has_feature("` Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/11956ec181a034b51a881ac9c059eea72c679a73.1651828453.git.christophe.leroy@csgroup.eu
2022-05-05powerpc/mm: Move get_unmapped_area functions to slice.cChristophe Leroy
hugetlb_get_unmapped_area() is now identical to the generic version if only RADIX is enabled, so move it to slice.c and let it fallback on the generic one when HASH MMU is not compiled in. Do the same with arch_get_unmapped_area() and arch_get_unmapped_area_topdown(). Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/b5d9c124e82889e0cb115c150915a0c0d84eb960.1649523076.git.christophe.leroy@csgroup.eu
2022-05-05powerpc/mm: Use generic_hugetlb_get_unmapped_area()Christophe Leroy
Use the generic version of arch_hugetlb_get_unmapped_area() which is now available at all time. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/05f77014c619061638ecc52a0a4136eb04cc2799.1649523076.git.christophe.leroy@csgroup.eu
2022-05-05powerpc/mm: Remove CONFIG_PPC_MM_SLICESChristophe Leroy
CONFIG_PPC_MM_SLICES is always selected by hash book3s/64. CONFIG_PPC_MM_SLICES is never selected by other platforms. Remove it. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Reviewed-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/dc2cdc204de8978574bf7c02329b6cfc4db0bce7.1649523076.git.christophe.leroy@csgroup.eu
2022-05-05powerpc/mm: Move vma_mmu_pagesize()Christophe Leroy
vma_mmu_pagesize() is only required for slices, otherwise there is a generic weak version doing the exact same thing. Move it to slice.c Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Reviewed-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/1302e000d529c93d07208f1fae90f938e7a551b4.1649523076.git.christophe.leroy@csgroup.eu
2022-02-12powerpc/mm: Update default hugetlb size earlyAneesh Kumar K.V
commit: d9c234005227 ("Do not depend on MAX_ORDER when grouping pages by mobility") introduced pageblock_order which will be used to group pages better. The kernel now groups pages based on the value of HPAGE_SHIFT. Hence HPAGE_SHIFT should be set before we call set_pageblock_order. set_pageblock_order happens early in the boot and default hugetlb page size should be initialized before that to compute the right pageblock_order value. Currently, default hugetlbe page size is set via arch_initcalls which happens late in the boot as shown via the below callstack: [c000000007383b10] [c000000001289328] hugetlbpage_init+0x2b8/0x2f8 [c000000007383bc0] [c0000000012749e4] do_one_initcall+0x14c/0x320 [c000000007383c90] [c00000000127505c] kernel_init_freeable+0x410/0x4e8 [c000000007383da0] [c000000000012664] kernel_init+0x30/0x15c [c000000007383e10] [c00000000000cf14] ret_from_kernel_thread+0x5c/0x64 and the pageblock_order initialization is done early during the boot. [c0000000018bfc80] [c0000000012ae120] set_pageblock_order+0x50/0x64 [c0000000018bfca0] [c0000000012b3d94] sparse_init+0x188/0x268 [c0000000018bfd60] [c000000001288bfc] initmem_init+0x28c/0x328 [c0000000018bfe50] [c00000000127b370] setup_arch+0x410/0x480 [c0000000018bfed0] [c00000000127401c] start_kernel+0xb8/0x934 [c0000000018bff90] [c00000000000d984] start_here_common+0x1c/0x98 delaying default hugetlb page size initialization implies the kernel will initialize pageblock_order to (MAX_ORDER - 1) which is not an optimal value for mobility grouping. IIUC we always had this issue. But it was not a problem for hash translation mode because (MAX_ORDER - 1) is the same as HUGETLB_PAGE_ORDER (8) in the case of hash (16MB). With radix, HUGETLB_PAGE_ORDER will be 5 (2M size) and hence pageblock_order should be 5 instead of 8. Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20220211065215.101767-1-aneesh.kumar@linux.ibm.com
2021-12-09powerpc/64s: Always define arch unmapped area callsNicholas Piggin
To avoid any functional changes to radix paths when building with hash MMU support disabled (and CONFIG_PPC_MM_SLICES=n), always define the arch get_unmapped_area calls on 64s platforms. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20211201144153.2456614-16-npiggin@gmail.com
2021-11-06hugetlbfs: extend the definition of hugepages parameter to support node ↵Zhenguo Yao
allocation We can specify the number of hugepages to allocate at boot. But the hugepages is balanced in all nodes at present. In some scenarios, we only need hugepages in one node. For example: DPDK needs hugepages which are in the same node as NIC. If DPDK needs four hugepages of 1G size in node1 and system has 16 numa nodes we must reserve 64 hugepages on the kernel cmdline. But only four hugepages are used. The others should be free after boot. If the system memory is low(for example: 64G), it will be an impossible task. So extend the hugepages parameter to support specifying hugepages on a specific node. For example add following parameter: hugepagesz=1G hugepages=0:1,1:3 It will allocate 1 hugepage in node0 and 3 hugepages in node1. Link: https://lkml.kernel.org/r/20211005054729.86457-1-yaozhenguo1@gmail.com Signed-off-by: Zhenguo Yao <yaozhenguo1@gmail.com> Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com> Cc: Zhenguo Yao <yaozhenguo1@gmail.com> Cc: Dan Carpenter <dan.carpenter@oracle.com> Cc: Nathan Chancellor <nathan@kernel.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Mike Rapoport <rppt@kernel.org> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-05hugetlb: pass vma into huge_pte_alloc() and huge_pmd_share()Peter Xu
Patch series "hugetlb: Disable huge pmd unshare for uffd-wp", v4. This series tries to disable huge pmd unshare of hugetlbfs backed memory for uffd-wp. Although uffd-wp of hugetlbfs is still during rfc stage, the idea of this series may be needed for multiple tasks (Axel's uffd minor fault series, and Mike's soft dirty series), so I picked it out from the larger series. This patch (of 4): It is a preparation work to be able to behave differently in the per architecture huge_pte_alloc() according to different VMA attributes. Pass it deeper into huge_pmd_share() so that we can avoid the find_vma() call. [peterx@redhat.com: build fix] Link: https://lkml.kernel.org/r/20210304164653.GB397383@xz-x1Link: https://lkml.kernel.org/r/20210218230633.15028-1-peterx@redhat.com Link: https://lkml.kernel.org/r/20210218230633.15028-2-peterx@redhat.com Signed-off-by: Peter Xu <peterx@redhat.com> Suggested-by: Mike Kravetz <mike.kravetz@oracle.com> Cc: Adam Ruprecht <ruprecht@google.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Alexey Dobriyan <adobriyan@gmail.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Anshuman Khandual <anshuman.khandual@arm.com> Cc: Axel Rasmussen <axelrasmussen@google.com> Cc: Cannon Matthews <cannonmatthews@google.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Chinwen Chang <chinwen.chang@mediatek.com> Cc: David Rientjes <rientjes@google.com> Cc: "Dr . David Alan Gilbert" <dgilbert@redhat.com> Cc: Huang Ying <ying.huang@intel.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jann Horn <jannh@google.com> Cc: Jerome Glisse <jglisse@redhat.com> Cc: Kirill A. Shutemov <kirill@shutemov.name> Cc: Lokesh Gidra <lokeshgidra@google.com> Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: "Michal Koutn" <mkoutny@suse.com> Cc: Michel Lespinasse <walken@google.com> Cc: Mike Rapoport <rppt@linux.vnet.ibm.com> Cc: Mina Almasry <almasrymina@google.com> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Oliver Upton <oupton@google.com> Cc: Shaohua Li <shli@fb.com> Cc: Shawn Anastasio <shawn@anastas.io> Cc: Steven Price <steven.price@arm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-02-11powerpc/mm: Enable compound page check for both THP and HugeTLBAneesh Kumar K.V
THP config results in compound pages. Make sure the kernel enables the PageCompound() check with CONFIG_HUGETLB_PAGE disabled and CONFIG_TRANSPARENT_HUGEPAGE enabled. This makes sure we correctly flush the icache with THP pages. flush_dcache_icache_page only matter for platforms that don't support COHERENT_ICACHE. Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20210203045812.234439-1-aneesh.kumar@linux.ibm.com
2021-01-30powerpc/mm/hugetlb: Make pseries_alloc_bootmem_huge_page() staticCédric Le Goater
pseries_alloc_bootmem_huge_page() is only used locally in alloc_bootmem_huge_page() and does not need to be external. It fixes this W=1 compile error : ../arch/powerpc/mm/hugetlbpage.c:220:12: error: no previous prototype for ‘pseries_alloc_bootmem_huge_page’ [-Werror=missing-prototypes] 220 | int __init pseries_alloc_bootmem_huge_page(struct hstate *hstate) | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Signed-off-by: Cédric Le Goater <clg@kaod.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20210104143206.695198-16-clg@kaod.org
2020-12-15powerpc/mm: Fix hugetlb_free_pmd_range() and hugetlb_free_pud_range()Christophe Leroy
Commit 7bfe54b5f165 ("powerpc/mm: Refactor the floor/ceiling check in hugetlb range freeing functions") inadvertely removed the mask applied to start parameter in those two functions, leading to the following crash on power9. LTP: starting hugemmap05_1 (hugemmap05 -m) ------------[ cut here ]------------ kernel BUG at arch/powerpc/mm/book3s64/pgtable.c:387! Oops: Exception in kernel mode, sig: 5 [#1] LE PAGE_SIZE=64K MMU=Radix SMP NR_CPUS=256 NUMA PowerNV ... CPU: 99 PID: 308 Comm: ksoftirqd/99 Tainted: G O 5.10.0-rc7-next-20201211 #1 NIP: c00000000005dbec LR: c0000000003352f4 CTR: 0000000000000000 REGS: c00020000bb6f830 TRAP: 0700 Tainted: G O (5.10.0-rc7-next-20201211) MSR: 900000000282b033 <SF,HV,VEC,VSX,EE,FP,ME,IR,DR,RI,LE> CR: 24002284 XER: 20040000 GPR00: c0000000003352f4 c00020000bb6fad0 c000000007f70b00 c0002000385b3ff0 GPR04: 0000000000000000 0000000000000003 c00020000bb6f8b4 0000000000000001 GPR08: 0000000000000001 0000000000000009 0000000000000008 0000000000000002 GPR12: 0000000024002488 c000201fff649c00 c000000007f2a20c 0000000000000000 GPR16: 0000000000000007 0000000000000000 c000000000194d10 c000000000194d10 GPR24: 0000000000000014 0000000000000015 c000201cc6e72398 c000000007fac4b4 GPR28: c000000007f2bf80 c000000007fac2f8 0000000000000008 c000200033870000 NIP [c00000000005dbec] __tlb_remove_table+0x1dc/0x1e0 pgtable_free at arch/powerpc/mm/book3s64/pgtable.c:387 (inlined by) __tlb_remove_table at arch/powerpc/mm/book3s64/pgtable.c:405 LR [c0000000003352f4] tlb_remove_table_rcu+0x54/0xa0 Call Trace: __tlb_remove_table+0x13c/0x1e0 (unreliable) tlb_remove_table_rcu+0x54/0xa0 __tlb_remove_table_free at mm/mmu_gather.c:101 (inlined by) tlb_remove_table_rcu at mm/mmu_gather.c:156 rcu_core+0x35c/0xbb0 rcu_do_batch at kernel/rcu/tree.c:2502 (inlined by) rcu_core at kernel/rcu/tree.c:2737 __do_softirq+0x480/0x704 run_ksoftirqd+0x74/0xd0 run_ksoftirqd at kernel/softirq.c:651 (inlined by) run_ksoftirqd at kernel/softirq.c:642 smpboot_thread_fn+0x278/0x320 kthread+0x1c4/0x1d0 ret_from_kernel_thread+0x5c/0x80 Properly apply the masks before calling pmd_free_tlb() and pud_free_tlb() respectively. Fixes: 7bfe54b5f165 ("powerpc/mm: Refactor the floor/ceiling check in hugetlb range freeing functions") Reported-by: Qian Cai <qcai@redhat.com> Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/56feccd7b6fcd98e353361a233fa7bb8e67c3164.1607780469.git.christophe.leroy@csgroup.eu
2020-12-09powerpc/mm: Refactor the floor/ceiling check in hugetlb range freeing functionsChristophe Leroy
All hugetlb range freeing functions have a verification like the following, which only differs by the mask used, depending on the page table level. start &= MASK; if (start < floor) return; if (ceiling) { ceiling &= MASK; if (! ceiling) return; } if (end - 1 > ceiling - 1) return; Refactor that into a helper function which takes the mask as an argument, returning true when [start;end[ is not fully contained inside [floor;ceiling[ Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/16a571bb32eb6e8cd44bda484c8d81cd8a25e6d7.1604668827.git.christophe.leroy@csgroup.eu
2020-09-15powerpc/8xx: Support 16k hugepages with 4k pagesChristophe Leroy
The 8xx has 4 page sizes: 4k, 16k, 512k and 8M 4k and 16k can be selected at build time as standard page sizes, and 512k and 8M are hugepages. When 4k standard pages are selected, 16k pages are not available. Allow 16k pages as hugepages when 4k pages are used. To allow that, implement arch_make_huge_pte() which receives the necessary arguments to allow setting the PTE in accordance with the page size: - 512 k pages must have _PAGE_HUGE and _PAGE_SPS. They are set by pte_mkhuge(). arch_make_huge_pte() does nothing. - 16 k pages must have only _PAGE_SPS. arch_make_huge_pte() clears _PAGE_HUGE. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/a518abc29266a708dfbccc8fce9ae6694fe4c2c6.1598862623.git.christophe.leroy@csgroup.eu
2020-09-15powerpc: Fix random segfault when freeing hugetlb rangeChristophe Leroy
The following random segfault is observed from time to time with map_hugetlb selftest: root@localhost:~# ./map_hugetlb 1 19 524288 kB hugepages Mapping 1 Mbytes Segmentation fault [ 31.219972] map_hugetlb[365]: segfault (11) at 117 nip 77974f8c lr 779a6834 code 1 in ld-2.23.so[77966000+21000] [ 31.220192] map_hugetlb[365]: code: 9421ffc0 480318d1 93410028 90010044 9361002c 93810030 93a10034 93c10038 [ 31.220307] map_hugetlb[365]: code: 93e1003c 93210024 8123007c 81430038 <80e90004> 814a0004 7f443a14 813a0004 [ 31.221911] BUG: Bad rss-counter state mm:(ptrval) type:MM_FILEPAGES val:33 [ 31.229362] BUG: Bad rss-counter state mm:(ptrval) type:MM_ANONPAGES val:5 This fault is due to hugetlb_free_pgd_range() freeing page tables that are also used by regular pages. As explain in the comment at the beginning of hugetlb_free_pgd_range(), the verification done in free_pgd_range() on floor and ceiling is not done here, which means hugetlb_free_pte_range() can free outside the expected range. As the verification cannot be done in hugetlb_free_pgd_range(), it must be done in hugetlb_free_pte_range(). Fixes: b250c8c08c79 ("powerpc/8xx: Manage 512k huge pages as standard pages.") Cc: stable@vger.kernel.org Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/f0cb2a5477cd87d1eaadb128042e20aeb2bc2859.1598860677.git.christophe.leroy@csgroup.eu
2020-07-29powerpc/hugetlb/cma: Allocate gigantic hugetlb pages using CMAAneesh Kumar K.V
commit: cf11e85fc08c ("mm: hugetlb: optionally allocate gigantic hugepages using cma") added support for allocating gigantic hugepages using CMA. This patch enables the same for powerpc Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200713150749.25245-1-aneesh.kumar@linux.ibm.com
2020-06-09mm: don't include asm/pgtable.h if linux/mm.h is already includedMike Rapoport
Patch series "mm: consolidate definitions of page table accessors", v2. The low level page table accessors (pXY_index(), pXY_offset()) are duplicated across all architectures and sometimes more than once. For instance, we have 31 definition of pgd_offset() for 25 supported architectures. Most of these definitions are actually identical and typically it boils down to, e.g. static inline unsigned long pmd_index(unsigned long address) { return (address >> PMD_SHIFT) & (PTRS_PER_PMD - 1); } static inline pmd_t *pmd_offset(pud_t *pud, unsigned long address) { return (pmd_t *)pud_page_vaddr(*pud) + pmd_index(address); } These definitions can be shared among 90% of the arches provided XYZ_SHIFT, PTRS_PER_XYZ and xyz_page_vaddr() are defined. For architectures that really need a custom version there is always possibility to override the generic version with the usual ifdefs magic. These patches introduce include/linux/pgtable.h that replaces include/asm-generic/pgtable.h and add the definitions of the page table accessors to the new header. This patch (of 12): The linux/mm.h header includes <asm/pgtable.h> to allow inlining of the functions involving page table manipulations, e.g. pte_alloc() and pmd_alloc(). So, there is no point to explicitly include <asm/pgtable.h> in the files that include <linux/mm.h>. The include statements in such cases are remove with a simple loop: for f in $(git grep -l "include <linux/mm.h>") ; do sed -i -e '/include <asm\/pgtable.h>/ d' $f done Signed-off-by: Mike Rapoport <rppt@linux.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Cain <bcain@codeaurora.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Chris Zankel <chris@zankel.net> Cc: "David S. Miller" <davem@davemloft.net> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Greentime Hu <green.hu@gmail.com> Cc: Greg Ungerer <gerg@linux-m68k.org> Cc: Guan Xuetao <gxt@pku.edu.cn> Cc: Guo Ren <guoren@kernel.org> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Helge Deller <deller@gmx.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Ley Foon Tan <ley.foon.tan@intel.com> Cc: Mark Salter <msalter@redhat.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Matt Turner <mattst88@gmail.com> Cc: Max Filippov <jcmvbkbc@gmail.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Michal Simek <monstr@monstr.eu> Cc: Mike Rapoport <rppt@kernel.org> Cc: Nick Hu <nickhu@andestech.com> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: Richard Weinberger <richard@nod.at> Cc: Rich Felker <dalias@libc.org> Cc: Russell King <linux@armlinux.org.uk> Cc: Stafford Horne <shorne@gmail.com> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tony Luck <tony.luck@intel.com> Cc: Vincent Chen <deanbo422@gmail.com> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: Will Deacon <will@kernel.org> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Link: http://lkml.kernel.org/r/20200514170327.31389-1-rppt@kernel.org Link: http://lkml.kernel.org/r/20200514170327.31389-2-rppt@kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-05Merge tag 'powerpc-5.8-1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc updates from Michael Ellerman: - Support for userspace to send requests directly to the on-chip GZIP accelerator on Power9. - Rework of our lockless page table walking (__find_linux_pte()) to make it safe against parallel page table manipulations without relying on an IPI for serialisation. - A series of fixes & enhancements to make our machine check handling more robust. - Lots of plumbing to add support for "prefixed" (64-bit) instructions on Power10. - Support for using huge pages for the linear mapping on 8xx (32-bit). - Remove obsolete Xilinx PPC405/PPC440 support, and an associated sound driver. - Removal of some obsolete 40x platforms and associated cruft. - Initial support for booting on Power10. - Lots of other small features, cleanups & fixes. Thanks to: Alexey Kardashevskiy, Alistair Popple, Andrew Donnellan, Andrey Abramov, Aneesh Kumar K.V, Balamuruhan S, Bharata B Rao, Bulent Abali, Cédric Le Goater, Chen Zhou, Christian Zigotzky, Christophe JAILLET, Christophe Leroy, Dmitry Torokhov, Emmanuel Nicolet, Erhard F., Gautham R. Shenoy, Geoff Levand, George Spelvin, Greg Kurz, Gustavo A. R. Silva, Gustavo Walbon, Haren Myneni, Hari Bathini, Joel Stanley, Jordan Niethe, Kajol Jain, Kees Cook, Leonardo Bras, Madhavan Srinivasan., Mahesh Salgaonkar, Markus Elfring, Michael Neuling, Michal Simek, Nathan Chancellor, Nathan Lynch, Naveen N. Rao, Nicholas Piggin, Oliver O'Halloran, Paul Mackerras, Pingfan Liu, Qian Cai, Ram Pai, Raphael Moreira Zinsly, Ravi Bangoria, Sam Bobroff, Sandipan Das, Segher Boessenkool, Stephen Rothwell, Sukadev Bhattiprolu, Tyrel Datwyler, Wolfram Sang, Xiongfeng Wang. * tag 'powerpc-5.8-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (299 commits) powerpc/pseries: Make vio and ibmebus initcalls pseries specific cxl: Remove dead Kconfig options powerpc: Add POWER10 architected mode powerpc/dt_cpu_ftrs: Add MMA feature powerpc/dt_cpu_ftrs: Enable Prefixed Instructions powerpc/dt_cpu_ftrs: Advertise support for ISA v3.1 if selected powerpc: Add support for ISA v3.1 powerpc: Add new HWCAP bits powerpc/64s: Don't set FSCR bits in INIT_THREAD powerpc/64s: Save FSCR to init_task.thread.fscr after feature init powerpc/64s: Don't let DT CPU features set FSCR_DSCR powerpc/64s: Don't init FSCR_DSCR in __init_FSCR() powerpc/32s: Fix another build failure with CONFIG_PPC_KUAP_DEBUG powerpc/module_64: Use special stub for _mcount() with -mprofile-kernel powerpc/module_64: Simplify check for -mprofile-kernel ftrace relocations powerpc/module_64: Consolidate ftrace code powerpc/32: Disable KASAN with pages bigger than 16k powerpc/uaccess: Don't set KUEP by default on book3s/32 powerpc/uaccess: Don't set KUAP by default on book3s/32 powerpc/8xx: Reduce time spent in allow_user_access() and friends ...
2020-06-04powerpc: add support for folded p4d page tablesMike Rapoport
Implement primitives necessary for the 4th level folding, add walks of p4d level where appropriate and replace 5level-fixup.h with pgtable-nop4d.h. [rppt@linux.ibm.com: powerpc/xmon: drop unused pgdir varialble in show_pte() function] Link: http://lkml.kernel.org/r/20200519181454.GI1059226@linux.ibm.com [rppt@linux.ibm.com; build fix] Link: http://lkml.kernel.org/r/20200423141845.GI13521@linux.ibm.com Signed-off-by: Mike Rapoport <rppt@linux.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Tested-by: Christophe Leroy <christophe.leroy@c-s.fr> # 8xx and 83xx Cc: Arnd Bergmann <arnd@arndb.de> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Brian Cain <bcain@codeaurora.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Geert Uytterhoeven <geert+renesas@glider.be> Cc: Guan Xuetao <gxt@pku.edu.cn> Cc: James Morse <james.morse@arm.com> Cc: Jonas Bonn <jonas@southpole.se> Cc: Julien Thierry <julien.thierry.kdev@gmail.com> Cc: Ley Foon Tan <ley.foon.tan@intel.com> Cc: Marc Zyngier <maz@kernel.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Paul Mackerras <paulus@samba.org> Cc: Rich Felker <dalias@libc.org> Cc: Russell King <linux@armlinux.org.uk> Cc: Stafford Horne <shorne@gmail.com> Cc: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi> Cc: Suzuki K Poulose <suzuki.poulose@arm.com> Cc: Tony Luck <tony.luck@intel.com> Cc: Will Deacon <will@kernel.org> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Link: http://lkml.kernel.org/r/20200414153455.21744-9-rppt@kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-03hugetlbfs: remove hugetlb_add_hstate() warning for existing hstateMike Kravetz
hugetlb_add_hstate() prints a warning if the hstate already exists. This was originally done as part of kernel command line parsing. If 'hugepagesz=' was specified more than once, the warning pr_warn("hugepagesz= specified twice, ignoring\n"); would be printed. Some architectures want to enable all huge page sizes. They would call hugetlb_add_hstate for all supported sizes. However, this was done after command line processing and as a result hstates could have already been created for some sizes. To make sure no warning were printed, there would often be code like: if (!size_to_hstate(size) hugetlb_add_hstate(ilog2(size) - PAGE_SHIFT) The only time we want to print the warning is as the result of command line processing. So, remove the warning from hugetlb_add_hstate and add it to the single arch independent routine processing "hugepagesz=". After this, calls to size_to_hstate() in arch specific code can be removed and hugetlb_add_hstate can be called without worrying about warning messages. [mike.kravetz@oracle.com: fix hugetlb initialization] Link: http://lkml.kernel.org/r/4c36c6ce-3774-78fa-abc4-b7346bf24348@oracle.com Link: http://lkml.kernel.org/r/20200428205614.246260-5-mike.kravetz@oracle.com Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Tested-by: Anders Roxell <anders.roxell@linaro.org> Acked-by: Mina Almasry <almasrymina@google.com> Acked-by: Gerald Schaefer <gerald.schaefer@de.ibm.com> [s390] Acked-by: Will Deacon <will@kernel.org> Cc: Albert Ou <aou@eecs.berkeley.edu> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Christophe Leroy <christophe.leroy@c-s.fr> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David S. Miller <davem@davemloft.net> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Longpeng <longpeng2@huawei.com> Cc: Nitesh Narayan Lal <nitesh@redhat.com> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: Peter Xu <peterx@redhat.com> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com> Cc: Qian Cai <cai@lca.pw> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Link: http://lkml.kernel.org/r/20200417185049.275845-4-mike.kravetz@oracle.com Link: http://lkml.kernel.org/r/20200428205614.246260-4-mike.kravetz@oracle.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-03hugetlbfs: move hugepagesz= parsing to arch independent codeMike Kravetz
Now that architectures provide arch_hugetlb_valid_size(), parsing of "hugepagesz=" can be done in architecture independent code. Create a single routine to handle hugepagesz= parsing and remove all arch specific routines. We can also remove the interface hugetlb_bad_size() as this is no longer used outside arch independent code. This also provides consistent behavior of hugetlbfs command line options. The hugepagesz= option should only be specified once for a specific size, but some architectures allow multiple instances. This appears to be more of an oversight when code was added by some architectures to set up ALL huge pages sizes. Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Tested-by: Sandipan Das <sandipan@linux.ibm.com> Reviewed-by: Peter Xu <peterx@redhat.com> Acked-by: Mina Almasry <almasrymina@google.com> Acked-by: Gerald Schaefer <gerald.schaefer@de.ibm.com> [s390] Acked-by: Will Deacon <will@kernel.org> Cc: Albert Ou <aou@eecs.berkeley.edu> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Christophe Leroy <christophe.leroy@c-s.fr> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David S. Miller <davem@davemloft.net> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Longpeng <longpeng2@huawei.com> Cc: Nitesh Narayan Lal <nitesh@redhat.com> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Anders Roxell <anders.roxell@linaro.org> Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com> Cc: Qian Cai <cai@lca.pw> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Link: http://lkml.kernel.org/r/20200417185049.275845-3-mike.kravetz@oracle.com Link: http://lkml.kernel.org/r/20200428205614.246260-3-mike.kravetz@oracle.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-03hugetlbfs: add arch_hugetlb_valid_sizeMike Kravetz
Patch series "Clean up hugetlb boot command line processing", v4. Longpeng(Mike) reported a weird message from hugetlb command line processing and proposed a solution [1]. While the proposed patch does address the specific issue, there are other related issues in command line processing. As hugetlbfs evolved, updates to command line processing have been made to meet immediate needs and not necessarily in a coordinated manner. The result is that some processing is done in arch specific code, some is done in arch independent code and coordination is problematic. Semantics can vary between architectures. The patch series does the following: - Define arch specific arch_hugetlb_valid_size routine used to validate passed huge page sizes. - Move hugepagesz= command line parsing out of arch specific code and into an arch independent routine. - Clean up command line processing to follow desired semantics and document those semantics. [1] https://lore.kernel.org/linux-mm/20200305033014.1152-1-longpeng2@huawei.com This patch (of 3): The architecture independent routine hugetlb_default_setup sets up the default huge pages size. It has no way to verify if the passed value is valid, so it accepts it and attempts to validate at a later time. This requires undocumented cooperation between the arch specific and arch independent code. For architectures that support more than one huge page size, provide a routine arch_hugetlb_valid_size to validate a huge page size. hugetlb_default_setup can use this to validate passed values. arch_hugetlb_valid_size will also be used in a subsequent patch to move processing of the "hugepagesz=" in arch specific code to a common routine in arch independent code. Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Gerald Schaefer <gerald.schaefer@de.ibm.com> [s390] Acked-by: Will Deacon <will@kernel.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Albert Ou <aou@eecs.berkeley.edu> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: David S. Miller <davem@davemloft.net> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Longpeng <longpeng2@huawei.com> Cc: Christophe Leroy <christophe.leroy@c-s.fr> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: Mina Almasry <almasrymina@google.com> Cc: Peter Xu <peterx@redhat.com> Cc: Nitesh Narayan Lal <nitesh@redhat.com> Cc: Anders Roxell <anders.roxell@linaro.org> Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com> Cc: Qian Cai <cai@lca.pw> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Link: http://lkml.kernel.org/r/20200428205614.246260-1-mike.kravetz@oracle.com Link: http://lkml.kernel.org/r/20200428205614.246260-2-mike.kravetz@oracle.com Link: http://lkml.kernel.org/r/20200417185049.275845-1-mike.kravetz@oracle.com Link: http://lkml.kernel.org/r/20200417185049.275845-2-mike.kravetz@oracle.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-05-26powerpc/8xx: Only 8M pages are hugepte pages nowChristophe Leroy
512k pages are now standard pages, so only 8M pages are hugepte. No more handling of normal page tables through hugepd allocation and freeing, and hugepte helpers can also be simplified. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/2c6135d57fb76eebf70673fbac3dc9e740767879.1589866984.git.christophe.leroy@csgroup.eu
2020-05-26powerpc/8xx: Manage 512k huge pages as standard pages.Christophe Leroy
At the time being, 512k huge pages are handled through hugepd page tables. The PMD entry is flagged as a hugepd pointer and it means that only 512k hugepages can be managed in that 4M block. However, the hugepd table has the same size as a normal page table, and 512k entries can therefore be nested with normal pages. On the 8xx, TLB loading is performed by software and allthough the page tables are organised to match the L1 and L2 level defined by the HW, all TLB entries have both L1 and L2 independent entries. It means that even if two TLB entries are associated with the same PMD entry, they can be loaded with different values in L1 part. The L1 entry contains the page size (PS field): - 00 for 4k and 16 pages - 01 for 512k pages - 11 for 8M pages By adding a flag for hugepages in the PTE (_PAGE_HUGE) and copying it into the lower bit of PS, we can then manage 512k pages with normal page tables: - PMD entry has PS=11 for 8M pages - PMD entry has PS=00 for other pages. As a PMD entry covers 4M areas, a PMD will either point to a hugepd table having a single entry to an 8M page, or the PMD will point to a standard page table which will have either entries to 4k or 16k or 512k pages. For 512k pages, as the L1 entry will not know it is a 512k page before the PTE is read, there will be 128 entries in the PTE as if it was 4k pages. But when loading the TLB, it will be flagged as a 512k page. Note that we can't use pmd_ptr() in asm/nohash/32/pgtable.h because it is not defined yet. In ITLB miss, we keep the possibility to opt it out as when kernel text is pinned and no user hugepages are used, we can save several instruction by not using r11. In DTLB miss, that's just one instruction so it's not worth bothering with it. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/002819e8e166bf81d24b24782d98de7c40905d8f.1589866984.git.christophe.leroy@csgroup.eu
2020-05-26powerpc/mm: Reduce hugepd size for 8M hugepages on 8xxChristophe Leroy
Commit 55c8fc3f4930 ("powerpc/8xx: reintroduce 16K pages with HW assistance") redefined pte_t as a struct of 4 pte_basic_t, because in 16K pages mode there are four identical entries in the page table. But hugepd entries for 8M pages require only one entry of size pte_basic_t. So there is no point in creating a cache for 4 entries page tables. Calculate PTE_T_ORDER using the size of pte_basic_t instead of pte_t. Define specific huge_pte helpers (set_huge_pte_at(), huge_pte_clear(), huge_ptep_set_wrprotect()) to write the pte in a single entry instead of using set_pte_at() which writes 4 identical entries in 16k pages mode. Also make sure that __ptep_set_access_flags() properly handle the huge_pte case. Define set_pte_filter() inline otherwise GCC doesn't inline it anymore because it is now used twice, and that gives a pretty suboptimal code because of pte_t being a struct of 4 entries. Those functions are also used for 512k pages which only require one entry as well allthough replicating it four times was harmless as 512k pages entries are spread every 128 bytes in the table. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/43050d1a0c2d6e1541cab9c1126fc80bc7015ebd.1589866984.git.christophe.leroy@csgroup.eu
2020-05-15powerpc/mm: Replace zero-length array with flexible-arrayGustavo A. R. Silva
The current codebase makes use of the zero-length array language extension to the C90 standard, but the preferred mechanism to declare variable-length types such as these ones is a flexible array member[1][2], introduced in C99: struct foo { int stuff; struct boo array[]; }; By making use of the mechanism above, we will get a compiler warning in case the flexible array does not occur last in the structure, which will help us prevent some kind of undefined behavior bugs from being inadvertently introduced[3] to the codebase from now on. Also, notice that, dynamic memory allocations won't be affected by this change: "Flexible array members have incomplete type, and so the sizeof operator may not be applied. As a quirk of the original implementation of zero-length arrays, sizeof evaluates to zero."[1] sizeof(flexible-array-member) triggers a warning because flexible array members have incomplete type[1]. There are some instances of code in which the sizeof operator is being incorrectly/erroneously applied to zero-length arrays and the result is zero. Such instances may be hiding some bugs. So, this work (flexible-array member conversions) will also help to get completely rid of those sorts of issues. This issue was found with the help of Coccinelle. [1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html [2] https://github.com/KSPP/linux/issues/21 [3] commit 76497732932f ("cxgb3/l2t: Fix undefined behaviour") Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200507185755.GA15014@embeddedor
2020-02-17powerpc/hugetlb: Fix 512k hugepages on 8xx with 16k page sizeChristophe Leroy
Commit 55c8fc3f4930 ("powerpc/8xx: reintroduce 16K pages with HW assistance") redefined pte_t as a struct of 4 pte_basic_t, because in 16K pages mode there are four identical entries in the page table. But the size of hugepage tables is calculated based of the size of (void *). Therefore, we end up with page tables of size 1k instead of 4k for 512k pages. As 512k hugepage tables are the same size as standard page tables, ie 4k, use the standard page tables instead of PGT_CACHE tables. Fixes: 3fb69c6a1a13 ("powerpc/8xx: Enable 512k hugepage support with HW assistance") Cc: stable@vger.kernel.org # v5.0+ Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/90ec56a2315be602494619ed0223bba3b0b8d619.1580997007.git.christophe.leroy@c-s.fr
2019-09-24mm: introduce compound_nr()Matthew Wilcox (Oracle)
Replace 1 << compound_order(page) with compound_nr(page). Minor improvements in readability. Link: http://lkml.kernel.org/r/20190721104612.19120-4-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Ira Weiny <ira.weiny@intel.com> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Michal Hocko <mhocko@suse.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-07-13Merge tag 'powerpc-5.3-1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc updates from Michael Ellerman: "Notable changes: - Removal of the NPU DMA code, used by the out-of-tree Nvidia driver, as well as some other functions only used by drivers that haven't (yet?) made it upstream. - A fix for a bug in our handling of hardware watchpoints (eg. perf record -e mem: ...) which could lead to register corruption and kernel crashes. - Enable HAVE_ARCH_HUGE_VMAP, which allows us to use large pages for vmalloc when using the Radix MMU. - A large but incremental rewrite of our exception handling code to use gas macros rather than multiple levels of nested CPP macros. And the usual small fixes, cleanups and improvements. Thanks to: Alastair D'Silva, Alexey Kardashevskiy, Andreas Schwab, Aneesh Kumar K.V, Anju T Sudhakar, Anton Blanchard, Arnd Bergmann, Athira Rajeev, Cédric Le Goater, Christian Lamparter, Christophe Leroy, Christophe Lombard, Christoph Hellwig, Daniel Axtens, Denis Efremov, Enrico Weigelt, Frederic Barrat, Gautham R. Shenoy, Geert Uytterhoeven, Geliang Tang, Gen Zhang, Greg Kroah-Hartman, Greg Kurz, Gustavo Romero, Krzysztof Kozlowski, Madhavan Srinivasan, Masahiro Yamada, Mathieu Malaterre, Michael Neuling, Nathan Lynch, Naveen N. Rao, Nicholas Piggin, Nishad Kamdar, Oliver O'Halloran, Qian Cai, Ravi Bangoria, Sachin Sant, Sam Bobroff, Satheesh Rajendran, Segher Boessenkool, Shaokun Zhang, Shawn Anastasio, Stewart Smith, Suraj Jitindar Singh, Thiago Jung Bauermann, YueHaibing" * tag 'powerpc-5.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (163 commits) powerpc/powernv/idle: Fix restore of SPRN_LDBAR for POWER9 stop state. powerpc/eeh: Handle hugepages in ioremap space ocxl: Update for AFU descriptor template version 1.1 powerpc/boot: pass CONFIG options in a simpler and more robust way powerpc/boot: add {get, put}_unaligned_be32 to xz_config.h powerpc/irq: Don't WARN continuously in arch_local_irq_restore() powerpc/module64: Use symbolic instructions names. powerpc/module32: Use symbolic instructions names. powerpc: Move PPC_HA() PPC_HI() and PPC_LO() to ppc-opcode.h powerpc/module64: Fix comment in R_PPC64_ENTRY handling powerpc/boot: Add lzo support for uImage powerpc/boot: Add lzma support for uImage powerpc/boot: don't force gzipped uImage powerpc/8xx: Add microcode patch to move SMC parameter RAM. powerpc/8xx: Use IO accessors in microcode programming. powerpc/8xx: replace #ifdefs by IS_ENABLED() in microcode.c powerpc/8xx: refactor programming of microcode CPM params. powerpc/8xx: refactor printing of microcode patch name. powerpc/8xx: Refactor microcode write powerpc/8xx: refactor writing of CPM microcode arrays ...
2019-07-12mm: move the powerpc hugepd code to mm/gup.cChristoph Hellwig
While only powerpc supports the hugepd case, the code is pretty generic and I'd like to keep all GUP internals in one place. Link: http://lkml.kernel.org/r/20190625143715.1689-15-hch@lst.de Signed-off-by: Christoph Hellwig <hch@lst.de> Cc: Andrey Konovalov <andreyknvl@google.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: David Miller <davem@davemloft.net> Cc: James Hogan <jhogan@kernel.org> Cc: Jason Gunthorpe <jgg@mellanox.com> Cc: Khalid Aziz <khalid.aziz@oracle.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Paul Burton <paul.burton@mips.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Rich Felker <dalias@libc.org> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-07-05powerpc/mm/hugetlb: Don't enable HugeTLB if we don't have a page table cacheAneesh Kumar K.V
This makes sure we don't enable HugeTLB if the cache is not configured. I am still not sure about this. IMHO hugetlb support should be a hardware support derivative and any cache allocation failure should be handled as I did in the earlier patch. But then if we were not able to create hugetlb page table cache, we can as well declare hugetlb support disabled thereby avoiding calling into allocation routines. Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-07-05powerpc/mm/hugetlb: Fix kernel crash if we fail to allocate page table cachesAneesh Kumar K.V
We only check for hugetlb allocations, because with hugetlb we do conditional registration. For PGD/PUD/PMD levels we register them always in pgtable_cache_init. Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-07-05powerpc/mm: Handle page table allocation failuresAneesh Kumar K.V
This fixes kernel crash that arises due to not handling page table allocation failures while allocating hugetlb page table. Fixes: e2b3d202d1db ("powerpc: Switch 16GB and 16MB explicit hugepages to a different page table format") Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-05-15powerpc/mm: Fix crashes with hugepages & 4K pagesMichael Ellerman
The recent commit to cleanup ifdefs in the hugepage initialisation led to crashes when using 4K pages as reported by Sachin: BUG: Kernel NULL pointer dereference at 0x0000001c Faulting instruction address: 0xc000000001d1e58c Oops: Kernel access of bad area, sig: 11 [#1] LE PAGE_SIZE=4K MMU=Hash SMP NR_CPUS=2048 NUMA pSeries ... CPU: 3 PID: 4635 Comm: futex_wake04 Tainted: G W O 5.1.0-next-20190507-autotest #1 NIP: c000000001d1e58c LR: c000000001d1e54c CTR: 0000000000000000 REGS: c000000004937890 TRAP: 0300 MSR: 8000000000009033 <SF,EE,ME,IR,DR,RI,LE> CR: 22424822 XER: 00000000 CFAR: c00000000183e9e0 DAR: 000000000000001c DSISR: 40000000 IRQMASK: 0 ... NIP kmem_cache_alloc+0xbc/0x5a0 LR kmem_cache_alloc+0x7c/0x5a0 Call Trace: huge_pte_alloc+0x580/0x950 hugetlb_fault+0x9a0/0x1250 handle_mm_fault+0x490/0x4a0 __do_page_fault+0x77c/0x1f00 do_page_fault+0x28/0x50 handle_page_fault+0x18/0x38 This is caused by us trying to allocate from a NULL kmem cache in __hugepte_alloc(). The kmem cache is NULL because it was never allocated in hugetlbpage_init(), because add_huge_page_size() returned an error. The reason add_huge_page_size() returned an error is a simple typo, we are calling check_and_get_huge_psize(size) when we should be passing shift instead. The fact that we're able to trigger this path when the kmem caches are NULL is a separate bug, ie. we should not advertise any hugepage sizes if we haven't setup the required caches for them. This was only seen with 4K pages, with 64K pages we don't need to allocate any extra kmem caches because the 16M hugepage just occupies a single entry at the PMD level. Fixes: 723f268f19da ("powerpc/mm: cleanup ifdef mess in add_huge_page_size()") Reported-by: Sachin Sant <sachinp@linux.ibm.com> Tested-by: Sachin Sant <sachinp@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Reviewed-by: Christophe Leroy <christophe.leroy@c-s.fr> Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
2019-05-06powerpc/mm: Fix hugetlb page initializationSachin Sant
This patch fixes a regression by using correct kernel config variable for HUGETLB_PAGE_SIZE_VARIABLE. Without this huge pages are disabled during kernel boot. [0.309496] hugetlbfs: disabling because there are no supported hugepage sizes Fixes: c5710cd20735 ("powerpc/mm: cleanup HPAGE_SHIFT setup") Reported-by: Sachin Sant <sachinp@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Tested-by: Sachin Sant <sachinp@linux.ibm.com> Reviewed-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-05-03powerpc/mm: cleanup remaining ifdef mess in hugetlbpage.cChristophe Leroy
Only 3 subarches support huge pages. So when it is either 2 of them, it is not the third one. And mmu_has_feature() is known by all subarches so IS_ENABLED() can be used instead of #ifdef Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-05-03powerpc/mm: cleanup HPAGE_SHIFT setupChristophe Leroy
Only book3s/64 may select default among several HPAGE_SHIFT at runtime. 8xx always defines 512K pages as default FSL_BOOK3E always defines 4M pages as default This patch limits HUGETLB_PAGE_SIZE_VARIABLE to book3s/64 moves the definitions in subarches files. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>