summaryrefslogtreecommitdiff
path: root/arch/powerpc/mm/kasan
AgeCommit message (Collapse)AuthorFilesLines
2024-02-05powerpc/kasan: Fix addr error caused by page alignmentJiangfeng Xiao1-0/+1
In kasan_init_region, when k_start is not page aligned, at the begin of for loop, k_cur = k_start & PAGE_MASK is less than k_start, and then `va = block + k_cur - k_start` is less than block, the addr va is invalid, because the memory address space from va to block is not alloced by memblock_alloc, which will not be reserved by memblock_reserve later, it will be used by other places. As a result, memory overwriting occurs. for example: int __init __weak kasan_init_region(void *start, size_t size) { [...] /* if say block(dcd97000) k_start(feef7400) k_end(feeff3fe) */ block = memblock_alloc(k_end - k_start, PAGE_SIZE); [...] for (k_cur = k_start & PAGE_MASK; k_cur < k_end; k_cur += PAGE_SIZE) { /* at the begin of for loop * block(dcd97000) va(dcd96c00) k_cur(feef7000) k_start(feef7400) * va(dcd96c00) is less than block(dcd97000), va is invalid */ void *va = block + k_cur - k_start; [...] } [...] } Therefore, page alignment is performed on k_start before memblock_alloc() to ensure the validity of the VA address. Fixes: 663c0c9496a6 ("powerpc/kasan: Fix shadow area set up for modules.") Signed-off-by: Jiangfeng Xiao <xiaojiangfeng@huawei.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/1705974359-43790-1-git-send-email-xiaojiangfeng@huawei.com
2023-07-17powerpc/kasan: Disable KCOV in KASAN codeBenjamin Gray1-0/+1
As per the generic KASAN code in mm/kasan, disable KCOV with KCOV_INSTRUMENT := n in the makefile. This fixes a ppc64 boot hang when KCOV and KASAN are enabled. kasan_early_init() gets called before a PACA is initialised, but the KCOV hook expects a valid PACA. Suggested-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Benjamin Gray <bgray@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20230710044143.146840-1-bgray@linux.ibm.com
2022-07-27powerpc/32s: Fix boot failure with KASAN + SMP + JUMP_LABEL_FEATURE_CHECK_DEBUGChristophe Leroy1-1/+1
Since commit 4291d085b0b0 ("powerpc/32s: Make pte_update() non atomic on 603 core"), pte_update() has been using mmu_has_feature(MMU_FTR_HPTE_TABLE) to avoid a useless atomic operation on 603 cores. When kasan_early_init() sets up the early zero shadow, it uses __set_pte_at(). On book3s/32, __set_pte_at() calls pte_update() when CONFIG_SMP is selected in order to ensure the preservation of _PAGE_HASHPTE in case of concurrent update of the PTE. But that's too early for mmu_has_feature(), so when CONFIG_JUMP_LABEL_FEATURE_CHECK_DEBUG is selected, mmu_has_feature() calls printk(). That's too early to call printk() because KASAN early zero shadow page is not set up yet. It leads to a deadlock. However, when kasan_early_init() is called, there is only one CPU running and no risk of concurrent PTE update. So __set_pte_at() can be called with the 'percpu' flag. With that flag set, the PTE is written directly instead of being written via pte_update(). Fixes: 4291d085b0b0 ("powerpc/32s: Make pte_update() non atomic on 603 core") Reported-by: Erhard Furtner <erhard_f@mailbox.org> Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/2ee707512b8b212b079b877f4ceb525a1606a3fb.1656655567.git.christophe.leroy@csgroup.eu
2022-06-29powerpc/64e: KASAN Full support for BOOK3E/64Christophe Leroy3-0/+136
We now have memory organised in a way that allows implementing KASAN. Unlike book3s/64, book3e always has translation active so the only thing needed to use KASAN is to setup an early zero shadow mapping just after setting a stack pointer and before calling early_setup(). The memory layout is now as follows +------------------------+ Kernel virtual map end (0xc000200000000000) | | | 16TB of KASAN map | | | +------------------------+ Kernel KASAN shadow map start | | | 16TB of IO map | | | +------------------------+ Kernel IO map start | | | 16TB of vmemmap | | | +------------------------+ Kernel vmemmap start | | | 16TB of vmap | | | +------------------------+ Kernel virt start (0xc000100000000000) | | | 64TB of linear mem | | | +------------------------+ Kernel linear (0xc.....) Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/0bef8beda27baf71e3b9e8b13e620fba6e19499b.1656427701.git.christophe.leroy@csgroup.eu
2022-05-22powerpc: Book3S 64-bit outline-only KASAN supportDaniel Axtens2-0/+103
Implement a limited form of KASAN for Book3S 64-bit machines running under the Radix MMU, supporting only outline mode. - Enable the compiler instrumentation to check addresses and maintain the shadow region. (This is the guts of KASAN which we can easily reuse.) - Require kasan-vmalloc support to handle modules and anything else in vmalloc space. - KASAN needs to be able to validate all pointer accesses, but we can't instrument all kernel addresses - only linear map and vmalloc. On boot, set up a single page of read-only shadow that marks all iomap and vmemmap accesses as valid. - Document KASAN in powerpc docs. Background ---------- KASAN support on Book3S is a bit tricky to get right: - It would be good to support inline instrumentation so as to be able to catch stack issues that cannot be caught with outline mode. - Inline instrumentation requires a fixed offset. - Book3S runs code with translations off ("real mode") during boot, including a lot of generic device-tree parsing code which is used to determine MMU features. [ppc64 mm note: The kernel installs a linear mapping at effective address c000...-c008.... This is a one-to-one mapping with physical memory from 0000... onward. Because of how memory accesses work on powerpc 64-bit Book3S, a kernel pointer in the linear map accesses the same memory both with translations on (accessing as an 'effective address'), and with translations off (accessing as a 'real address'). This works in both guests and the hypervisor. For more details, see s5.7 of Book III of version 3 of the ISA, in particular the Storage Control Overview, s5.7.3, and s5.7.5 - noting that this KASAN implementation currently only supports Radix.] - Some code - most notably a lot of KVM code - also runs with translations off after boot. - Therefore any offset has to point to memory that is valid with translations on or off. One approach is just to give up on inline instrumentation. This way boot-time checks can be delayed until after the MMU is set is up, and we can just not instrument any code that runs with translations off after booting. Take this approach for now and require outline instrumentation. Previous attempts allowed inline instrumentation. However, they came with some unfortunate restrictions: only physically contiguous memory could be used and it had to be specified at compile time. Maybe we can do better in the future. [paulus@ozlabs.org - Rebased onto 5.17. Note that a kernel with CONFIG_KASAN=y will crash during boot on a machine using HPT translation because not all the entry points to the generic KASAN code are protected with a call to kasan_arch_is_ready().] Originally-by: Balbir Singh <bsingharora@gmail.com> # ppc64 out-of-line radix version Signed-off-by: Daniel Axtens <dja@axtens.net> Signed-off-by: Paul Mackerras <paulus@ozlabs.org> [mpe: Update copyright year and comment formatting] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/YoTE69OQwiG7z+Gu@cleo
2022-05-22powerpc/mm/kasan: rename kasan_init_32.c to init_32.cDaniel Axtens2-1/+1
kasan is already implied by the directory name, we don't need to repeat it. Suggested-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Daniel Axtens <dja@axtens.net> Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/YoTEyoi+xu9brJYe@cleo
2022-02-03powerpc/kasan: Fix early region not updated correctlyChen Jingwen1-2/+1
The shadow's page table is not updated when PTE_RPN_SHIFT is 24 and PAGE_SHIFT is 12. It not only causes false positives but also false negative as shown the following text. Fix it by bringing the logic of kasan_early_shadow_page_entry here. 1. False Positive: ================================================================== BUG: KASAN: vmalloc-out-of-bounds in pcpu_alloc+0x508/0xa50 Write of size 16 at addr f57f3be0 by task swapper/0/1 CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.15.0-12267-gdebe436e77c7 #1 Call Trace: [c80d1c20] [c07fe7b8] dump_stack_lvl+0x4c/0x6c (unreliable) [c80d1c40] [c02ff668] print_address_description.constprop.0+0x88/0x300 [c80d1c70] [c02ff45c] kasan_report+0x1ec/0x200 [c80d1cb0] [c0300b20] kasan_check_range+0x160/0x2f0 [c80d1cc0] [c03018a4] memset+0x34/0x90 [c80d1ce0] [c0280108] pcpu_alloc+0x508/0xa50 [c80d1d40] [c02fd7bc] __kmem_cache_create+0xfc/0x570 [c80d1d70] [c0283d64] kmem_cache_create_usercopy+0x274/0x3e0 [c80d1db0] [c2036580] init_sd+0xc4/0x1d0 [c80d1de0] [c00044a0] do_one_initcall+0xc0/0x33c [c80d1eb0] [c2001624] kernel_init_freeable+0x2c8/0x384 [c80d1ef0] [c0004b14] kernel_init+0x24/0x170 [c80d1f10] [c001b26c] ret_from_kernel_thread+0x5c/0x64 Memory state around the buggy address: f57f3a80: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f57f3b00: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 >f57f3b80: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 ^ f57f3c00: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f57f3c80: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 ================================================================== 2. False Negative (with KASAN tests): ================================================================== Before fix: ok 45 - kmalloc_double_kzfree # vmalloc_oob: EXPECTATION FAILED at lib/test_kasan.c:1039 KASAN failure expected in "((volatile char *)area)[3100]", but none occurred not ok 46 - vmalloc_oob not ok 1 - kasan ================================================================== After fix: ok 1 - kasan Fixes: cbd18991e24fe ("powerpc/mm: Fix an Oops in kasan_mmu_init()") Cc: stable@vger.kernel.org # 5.4.x Signed-off-by: Chen Jingwen <chenjingwen6@huawei.com> Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20211229035226.59159-1-chenjingwen6@huawei.com
2022-01-16powerpc/32s: Fix kasan_init_region() for KASANChristophe Leroy1-28/+31
It has been reported some configuration where the kernel doesn't boot with KASAN enabled. This is due to wrong BAT allocation for the KASAN area: ---[ Data Block Address Translation ]--- 0: 0xc0000000-0xcfffffff 0x00000000 256M Kernel rw m 1: 0xd0000000-0xdfffffff 0x10000000 256M Kernel rw m 2: 0xe0000000-0xefffffff 0x20000000 256M Kernel rw m 3: 0xf8000000-0xf9ffffff 0x2a000000 32M Kernel rw m 4: 0xfa000000-0xfdffffff 0x2c000000 64M Kernel rw m A BAT must have both virtual and physical addresses alignment matching the size of the BAT. This is not the case for BAT 4 above. Fix kasan_init_region() by using block_size() function that is in book3s32/mmu.c. To be able to reuse it here, make it non static and change its name to bat_block_size() in order to avoid name conflict with block_size() defined in <linux/blkdev.h> Also reuse find_free_bat() to avoid an error message from setbat() when no BAT is available. And allocate memory outside of linear memory mapping to avoid wasting that precious space. With this change we get correct alignment for BATs and KASAN shadow memory is allocated outside the linear memory space. ---[ Data Block Address Translation ]--- 0: 0xc0000000-0xcfffffff 0x00000000 256M Kernel rw 1: 0xd0000000-0xdfffffff 0x10000000 256M Kernel rw 2: 0xe0000000-0xefffffff 0x20000000 256M Kernel rw 3: 0xf8000000-0xfbffffff 0x7c000000 64M Kernel rw 4: 0xfc000000-0xfdffffff 0x7a000000 32M Kernel rw Fixes: 7974c4732642 ("powerpc/32s: Implement dedicated kasan_init_region()") Cc: stable@vger.kernel.org Reported-by: Maxime Bizon <mbizon@freebox.fr> Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Tested-by: Maxime Bizon <mbizon@freebox.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/7a50ef902494d1325227d47d33dada01e52e5518.1641818726.git.christophe.leroy@csgroup.eu
2021-11-30powerpc/32s: Fix shift-out-of-bounds in KASAN initChristophe Leroy1-1/+2
================================================================================ UBSAN: shift-out-of-bounds in arch/powerpc/mm/kasan/book3s_32.c:22:23 shift exponent -1 is negative CPU: 0 PID: 0 Comm: swapper Not tainted 5.15.5-gentoo-PowerMacG4 #9 Call Trace: [c214be60] [c0ba0048] dump_stack_lvl+0x80/0xb0 (unreliable) [c214be80] [c0b99288] ubsan_epilogue+0x10/0x5c [c214be90] [c0b98fe0] __ubsan_handle_shift_out_of_bounds+0x94/0x138 [c214bf00] [c1c0f010] kasan_init_region+0xd8/0x26c [c214bf30] [c1c0ed84] kasan_init+0xc0/0x198 [c214bf70] [c1c08024] setup_arch+0x18/0x54c [c214bfc0] [c1c037f0] start_kernel+0x90/0x33c [c214bff0] [00003610] 0x3610 ================================================================================ This happens when the directly mapped memory is a power of 2. Fix it by checking the shift and set the result to 0 when shift is -1 Fixes: 7974c4732642 ("powerpc/32s: Implement dedicated kasan_init_region()") Reported-by: Erhard Furtner <erhard_f@mailbox.org> Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://bugzilla.kernel.org/show_bug.cgi?id=215169 Link: https://lore.kernel.org/r/15cbc3439d4ad988b225e2119ec99502a5cc6ad3.1638261744.git.christophe.leroy@csgroup.eu
2020-10-16Merge tag 'powerpc-5.10-1' of ↵Linus Torvalds1-22/+9
git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc updates from Michael Ellerman: - A series from Nick adding ARCH_WANT_IRQS_OFF_ACTIVATE_MM & selecting it for powerpc, as well as a related fix for sparc. - Remove support for PowerPC 601. - Some fixes for watchpoints & addition of a new ptrace flag for detecting ISA v3.1 (Power10) watchpoint features. - A fix for kernels using 4K pages and the hash MMU on bare metal Power9 systems with > 16TB of RAM, or RAM on the 2nd node. - A basic idle driver for shallow stop states on Power10. - Tweaks to our sched domains code to better inform the scheduler about the hardware topology on Power9/10, where two SMT4 cores can be presented by firmware as an SMT8 core. - A series doing further reworks & cleanups of our EEH code. - Addition of a filter for RTAS (firmware) calls done via sys_rtas(), to prevent root from overwriting kernel memory. - Other smaller features, fixes & cleanups. Thanks to: Alexey Kardashevskiy, Andrew Donnellan, Aneesh Kumar K.V, Athira Rajeev, Biwen Li, Cameron Berkenpas, Cédric Le Goater, Christophe Leroy, Christoph Hellwig, Colin Ian King, Daniel Axtens, David Dai, Finn Thain, Frederic Barrat, Gautham R. Shenoy, Greg Kurz, Gustavo Romero, Ira Weiny, Jason Yan, Joel Stanley, Jordan Niethe, Kajol Jain, Konrad Rzeszutek Wilk, Laurent Dufour, Leonardo Bras, Liu Shixin, Luca Ceresoli, Madhavan Srinivasan, Mahesh Salgaonkar, Nathan Lynch, Nicholas Mc Guire, Nicholas Piggin, Nick Desaulniers, Oliver O'Halloran, Pedro Miraglia Franco de Carvalho, Pratik Rajesh Sampat, Qian Cai, Qinglang Miao, Ravi Bangoria, Russell Currey, Satheesh Rajendran, Scott Cheloha, Segher Boessenkool, Srikar Dronamraju, Stan Johnson, Stephen Kitt, Stephen Rothwell, Thiago Jung Bauermann, Tyrel Datwyler, Vaibhav Jain, Vaidyanathan Srinivasan, Vasant Hegde, Wang Wensheng, Wolfram Sang, Yang Yingliang, zhengbin. * tag 'powerpc-5.10-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (228 commits) Revert "powerpc/pci: unmap legacy INTx interrupts when a PHB is removed" selftests/powerpc: Fix eeh-basic.sh exit codes cpufreq: powernv: Fix frame-size-overflow in powernv_cpufreq_reboot_notifier powerpc/time: Make get_tb() common to PPC32 and PPC64 powerpc/time: Make get_tbl() common to PPC32 and PPC64 powerpc/time: Remove get_tbu() powerpc/time: Avoid using get_tbl() and get_tbu() internally powerpc/time: Make mftb() common to PPC32 and PPC64 powerpc/time: Rename mftbl() to mftb() powerpc/32s: Remove #ifdef CONFIG_PPC_BOOK3S_32 in head_book3s_32.S powerpc/32s: Rename head_32.S to head_book3s_32.S powerpc/32s: Setup the early hash table at all time. powerpc/time: Remove ifdef in get_dec() and set_dec() powerpc: Remove get_tb_or_rtc() powerpc: Remove __USE_RTC() powerpc: Tidy up a bit after removal of PowerPC 601. powerpc: Remove support for PowerPC 601 powerpc: Remove PowerPC 601 powerpc: Drop SYNC_601() ISYNC_601() and SYNC() powerpc: Remove CONFIG_PPC601_SYNC_FIX ...
2020-10-14arch, drivers: replace for_each_membock() with for_each_mem_range()Mike Rapoport1-4/+4
There are several occurrences of the following pattern: for_each_memblock(memory, reg) { start = __pfn_to_phys(memblock_region_memory_base_pfn(reg); end = __pfn_to_phys(memblock_region_memory_end_pfn(reg)); /* do something with start and end */ } Using for_each_mem_range() iterator is more appropriate in such cases and allows simpler and cleaner code. [akpm@linux-foundation.org: fix arch/arm/mm/pmsa-v7.c build] [rppt@linux.ibm.com: mips: fix cavium-octeon build caused by memblock refactoring] Link: http://lkml.kernel.org/r/20200827124549.GD167163@linux.ibm.com Signed-off-by: Mike Rapoport <rppt@linux.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Baoquan He <bhe@redhat.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Daniel Axtens <dja@axtens.net> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Emil Renner Berthing <kernel@esmil.dk> Cc: Hari Bathini <hbathini@linux.ibm.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jonathan Cameron <Jonathan.Cameron@huawei.com> Cc: Marek Szyprowski <m.szyprowski@samsung.com> Cc: Max Filippov <jcmvbkbc@gmail.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Michal Simek <monstr@monstr.eu> Cc: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: Peter Zijlstra <peterz@infradead.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: Will Deacon <will@kernel.org> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Link: https://lkml.kernel.org/r/20200818151634.14343-13-rppt@kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-08powerpc/32s: Setup the early hash table at all time.Christophe Leroy1-19/+0
At the time being, an early hash table is set up when CONFIG_KASAN is selected. There is nothing wrong with setting such an early hash table all the time, even if it is not used. This is a statically allocated 256 kB table which lies in the init data section. This makes the code simpler and may in the future allow to setup early IO mappings with fixmap instead of hard coding BATs. Put create_hpte() and flush_hash_pages() in the .ref.text section in order to avoid warning for the reference to early_hash[]. This reference is removed by MMU_init_hw_patch() before init memory is freed. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/b8f8101c368b8a6451844a58d7bd7d83c14cf2aa.1601566529.git.christophe.leroy@csgroup.eu
2020-09-15powerpc/kasan: Fix CONFIG_KASAN_VMALLOC for 8xxChristophe Leroy1-3/+9
Before the commit identified below, pages tables allocation was performed after the allocation of final shadow area for linear memory. But that commit switched the order, leading to page tables being already allocated at the time 8xx kasan_init_shadow_8M() is called. Due to this, kasan_init_shadow_8M() doesn't map the needed shadow entries because there are already page tables. kasan_init_shadow_8M() installs huge PMD entries instead of page tables. We could at that time free the page tables, but there is no point in creating page tables that get freed before being used. Only book3s/32 hash needs early allocation of page tables. For other variants, we can keep the initial order and create remaining page tables after the allocation of final shadow memory for linear mem. Move back the allocation of shadow page tables for CONFIG_KASAN_VMALLOC into kasan_init() after the loop which creates final shadow memory for linear mem. Fixes: 41ea93cf7ba4 ("powerpc/kasan: Fix shadow pages allocation failure") Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/8ae4554357da4882612644a74387ae05525b2aaa.1599800716.git.christophe.leroy@csgroup.eu
2020-08-07Merge branch 'akpm' (patches from Andrew)Linus Torvalds2-2/+0
Merge misc updates from Andrew Morton: - a few MM hotfixes - kthread, tools, scripts, ntfs and ocfs2 - some of MM Subsystems affected by this patch series: kthread, tools, scripts, ntfs, ocfs2 and mm (hofixes, pagealloc, slab-generic, slab, slub, kcsan, debug, pagecache, gup, swap, shmem, memcg, pagemap, mremap, mincore, sparsemem, vmalloc, kasan, pagealloc, hugetlb and vmscan). * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (162 commits) mm: vmscan: consistent update to pgrefill mm/vmscan.c: fix typo khugepaged: khugepaged_test_exit() check mmget_still_valid() khugepaged: retract_page_tables() remember to test exit khugepaged: collapse_pte_mapped_thp() protect the pmd lock khugepaged: collapse_pte_mapped_thp() flush the right range mm/hugetlb: fix calculation of adjust_range_if_pmd_sharing_possible mm: thp: replace HTTP links with HTTPS ones mm/page_alloc: fix memalloc_nocma_{save/restore} APIs mm/page_alloc.c: skip setting nodemask when we are in interrupt mm/page_alloc: fallbacks at most has 3 elements mm/page_alloc: silence a KASAN false positive mm/page_alloc.c: remove unnecessary end_bitidx for [set|get]_pfnblock_flags_mask() mm/page_alloc.c: simplify pageblock bitmap access mm/page_alloc.c: extract the common part in pfn_to_bitidx() mm/page_alloc.c: replace the definition of NR_MIGRATETYPE_BITS with PB_migratetype_bits mm/shuffle: remove dynamic reconfiguration mm/memory_hotplug: document why shuffle_zone() is relevant mm/page_alloc: remove nr_free_pagecache_pages() mm: remove vm_total_pages ...
2020-08-07mm: remove unneeded includes of <asm/pgalloc.h>Mike Rapoport2-2/+0
Patch series "mm: cleanup usage of <asm/pgalloc.h>" Most architectures have very similar versions of pXd_alloc_one() and pXd_free_one() for intermediate levels of page table. These patches add generic versions of these functions in <asm-generic/pgalloc.h> and enable use of the generic functions where appropriate. In addition, functions declared and defined in <asm/pgalloc.h> headers are used mostly by core mm and early mm initialization in arch and there is no actual reason to have the <asm/pgalloc.h> included all over the place. The first patch in this series removes unneeded includes of <asm/pgalloc.h> In the end it didn't work out as neatly as I hoped and moving pXd_alloc_track() definitions to <asm-generic/pgalloc.h> would require unnecessary changes to arches that have custom page table allocations, so I've decided to move lib/ioremap.c to mm/ and make pgalloc-track.h local to mm/. This patch (of 8): In most cases <asm/pgalloc.h> header is required only for allocations of page table memory. Most of the .c files that include that header do not use symbols declared in <asm/pgalloc.h> and do not require that header. As for the other header files that used to include <asm/pgalloc.h>, it is possible to move that include into the .c file that actually uses symbols from <asm/pgalloc.h> and drop the include from the header file. The process was somewhat automated using sed -i -E '/[<"]asm\/pgalloc\.h/d' \ $(grep -L -w -f /tmp/xx \ $(git grep -E -l '[<"]asm/pgalloc\.h')) where /tmp/xx contains all the symbols defined in arch/*/include/asm/pgalloc.h. [rppt@linux.ibm.com: fix powerpc warning] Signed-off-by: Mike Rapoport <rppt@linux.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Pekka Enberg <penberg@kernel.org> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> [m68k] Cc: Abdul Haleem <abdhalee@linux.vnet.ibm.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: Joerg Roedel <joro@8bytes.org> Cc: Max Filippov <jcmvbkbc@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Satheesh Rajendran <sathnaga@linux.vnet.ibm.com> Cc: Stafford Horne <shorne@gmail.com> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Joerg Roedel <jroedel@suse.de> Cc: Matthew Wilcox <willy@infradead.org> Link: http://lkml.kernel.org/r/20200627143453.31835-1-rppt@kernel.org Link: http://lkml.kernel.org/r/20200627143453.31835-2-rppt@kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-07-26powerpc: Use MODULES_VADDR if definedChristophe Leroy1-0/+6
In order to allow allocation of modules outside of vmalloc space, use MODULES_VADDR and MODULES_END when MODULES_VADDR is defined. Redefine module_alloc() when MODULES_VADDR defined. Unmap corresponding KASAN shadow memory. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/7ecf5fff1eef67d450e73fc412b6ec3818483d75.1593428200.git.christophe.leroy@csgroup.eu
2020-07-15powerpc/kasan: Fix shadow pages allocation failureChristophe Leroy1-12/+13
Doing kasan pages allocation in MMU_init is too early, kernel doesn't have access yet to the entire memory space and memblock_alloc() fails when the kernel is a bit big. Do it from kasan_init() instead. Fixes: 2edb16efc899 ("powerpc/32: Add KASAN support") Fixes: d2a91cef9bbd ("powerpc/kasan: Fix shadow pages allocation failure") Cc: stable@vger.kernel.org Reported-by: Erhard F. <erhard_f@mailbox.org> Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://bugzilla.kernel.org/show_bug.cgi?id=208181 Link: https://lore.kernel.org/r/63048fcea8a1c02f75429ba3152f80f7853f87fc.1593690707.git.christophe.leroy@csgroup.eu
2020-07-15Revert "powerpc/kasan: Fix shadow pages allocation failure"Christophe Leroy1-3/+1
This reverts commit d2a91cef9bbdeb87b7449fdab1a6be6000930210. This commit moved too much work in kasan_init(). The allocation of shadow pages has to be moved for the reason explained in that patch, but the allocation of page tables still need to be done before switching to the final hash table. First revert the incorrect commit, following patch redoes it properly. Fixes: d2a91cef9bbd ("powerpc/kasan: Fix shadow pages allocation failure") Cc: stable@vger.kernel.org Reported-by: Erhard F. <erhard_f@mailbox.org> Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://bugzilla.kernel.org/show_bug.cgi?id=208181 Link: https://lore.kernel.org/r/3667deb0911affbf999b99f87c31c77d5e870cd2.1593690707.git.christophe.leroy@csgroup.eu
2020-06-09mm: pgtable: add shortcuts for accessing kernel PMD and PTEMike Rapoport3-7/+7
The powerpc 32-bit implementation of pgtable has nice shortcuts for accessing kernel PMD and PTE for a given virtual address. Make these helpers available for all architectures. [rppt@linux.ibm.com: microblaze: fix page table traversal in setup_rt_frame()] Link: http://lkml.kernel.org/r/20200518191511.GD1118872@kernel.org [akpm@linux-foundation.org: s/pmd_ptr_k/pmd_off_k/ in various powerpc places] 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: 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/20200514170327.31389-9-rppt@kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-05-26powerpc/32s: Implement dedicated kasan_init_region()Christophe Leroy3-1/+59
Implement a kasan_init_region() dedicated to book3s/32 that allocates KASAN regions using BATs. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/709e821602b48a1d7c211a9b156da26db98c3e9d.1589866984.git.christophe.leroy@csgroup.eu
2020-05-26powerpc/8xx: Implement dedicated kasan_init_region()Christophe Leroy2-0/+75
Implement a kasan_init_region() dedicated to 8xx that allocates KASAN regions using huge pages. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/d2d60202a8821dc81cffe6ff59cc13c15b7e4bb6.1589866984.git.christophe.leroy@csgroup.eu
2020-05-20powerpc/kasan: Declare kasan_init_region() weakChristophe Leroy1-10/+11
In order to alloc sub-arches to alloc KASAN regions using optimised methods (Huge pages on 8xx, BATs on BOOK3S, ...), declare kasan_init_region() weak. Also make kasan_init_shadow_page_tables() accessible from outside, so that it can be called from the specific kasan_init_region() functions if needed. And populate remaining KASAN address space only once performed the region mapping, to allow 8xx to allocate hugepd instead of standard page tables for mapping via 8M hugepages. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/3c1ce419fa1b5a4171b92d7fb16455ca17e1b96d.1589866984.git.christophe.leroy@csgroup.eu
2020-05-20powerpc/kasan: Refactor update of early shadow mappingsChristophe Leroy1-21/+18
kasan_remap_early_shadow_ro() and kasan_unmap_early_shadow_vmalloc() are both updating the early shadow mapping: the first one sets the mapping read-only while the other clears the mapping. Refactor and create kasan_update_early_region() Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/8c496c0828de2608c7c940c45525d177e91b6f1b.1589866984.git.christophe.leroy@csgroup.eu
2020-05-20powerpc/kasan: Remove unnecessary page table lockingChristophe Leroy1-15/+4
Commit 45ff3c559585 ("powerpc/kasan: Fix parallel loading of modules.") added spinlocks to manage parallele module loading. Since then commit 47febbeeec44 ("powerpc/32: Force KASAN_VMALLOC for modules") converted the module loading to KASAN_VMALLOC. The spinlocking has then become unneeded and can be removed to simplify kasan_init_shadow_page_tables() Also remove inclusion of linux/moduleloader.h and linux/vmalloc.h which are not needed anymore since the removal of modules management. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/81a4d3aee8b82bc1355595935c8f4ad9d3b22a83.1589866984.git.christophe.leroy@csgroup.eu
2020-05-20powerpc/kasan: Fix shadow pages allocation failureChristophe Leroy1-1/+3
Doing kasan pages allocation in MMU_init is too early, kernel doesn't have access yet to the entire memory space and memblock_alloc() fails when the kernel is a bit big. Do it from kasan_init() instead. Fixes: 2edb16efc899 ("powerpc/32: Add KASAN support") Cc: stable@vger.kernel.org Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/c24163ee5d5f8cdf52fefa45055ceb35435b8f15.1589866984.git.christophe.leroy@csgroup.eu
2020-05-20powerpc/kasan: Fix error detection on memory allocationChristophe Leroy1-3/+2
In case (k_start & PAGE_MASK) doesn't equal (kstart), 'va' will never be NULL allthough 'block' is NULL Check the return of memblock_alloc() directly instead of the resulting address in the loop. Fixes: 509cd3f2b473 ("powerpc/32: Simplify KASAN init") Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/7cb8ca82042bfc45a5cfe726c921cd7e7eeb12a3.1589866984.git.christophe.leroy@csgroup.eu
2020-04-05Merge tag 'powerpc-5.7-1' of ↵Linus Torvalds1-5/+5
git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc updates from Michael Ellerman: "Slightly late as I had to rebase mid-week to insert a bug fix: - A large series from Nick for 64-bit to further rework our exception vectors, and rewrite portions of the syscall entry/exit and interrupt return in C. The result is much easier to follow code that is also faster in general. - Cleanup of our ptrace code to split various parts out that had become badly intertwined with #ifdefs over the years. - Changes to our NUMA setup under the PowerVM hypervisor which should hopefully avoid non-sensical topologies which can lead to warnings from the workqueue code and other problems. - MAINTAINERS updates to remove some of our old orphan entries and update the status of others. - Quite a few other small changes and fixes all over the map. Thanks to: Abdul Haleem, afzal mohammed, Alexey Kardashevskiy, Andrew Donnellan, Aneesh Kumar K.V, Balamuruhan S, Cédric Le Goater, Chen Zhou, Christophe JAILLET, Christophe Leroy, Christoph Hellwig, Clement Courbet, Daniel Axtens, David Gibson, Douglas Miller, Fabiano Rosas, Fangrui Song, Ganesh Goudar, Gautham R. Shenoy, Greg Kroah-Hartman, Greg Kurz, Gustavo Luiz Duarte, Hari Bathini, Ilie Halip, Jan Kara, Joe Lawrence, Joe Perches, Kajol Jain, Larry Finger, Laurentiu Tudor, Leonardo Bras, Libor Pechacek, Madhavan Srinivasan, Mahesh Salgaonkar, Masahiro Yamada, Masami Hiramatsu, Mauricio Faria de Oliveira, Michael Neuling, Michal Suchanek, Mike Rapoport, Nageswara R Sastry, Nathan Chancellor, Nathan Lynch, Naveen N. Rao, Nicholas Piggin, Nick Desaulniers, Oliver O'Halloran, Po-Hsu Lin, Pratik Rajesh Sampat, Rasmus Villemoes, Ravi Bangoria, Roman Bolshakov, Sam Bobroff, Sandipan Das, Santosh S, Sedat Dilek, Segher Boessenkool, Shilpasri G Bhat, Sourabh Jain, Srikar Dronamraju, Stephen Rothwell, Tyrel Datwyler, Vaibhav Jain, YueHaibing" * tag 'powerpc-5.7-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (158 commits) powerpc: Make setjmp/longjmp signature standard powerpc/cputable: Remove unnecessary copy of cpu_spec->oprofile_type powerpc: Suppress .eh_frame generation powerpc: Drop -fno-dwarf2-cfi-asm powerpc/32: drop unused ISA_DMA_THRESHOLD powerpc/powernv: Add documentation for the opal sensor_groups sysfs interfaces selftests/powerpc: Fix try-run when source tree is not writable powerpc/vmlinux.lds: Explicitly retain .gnu.hash powerpc/ptrace: move ptrace_triggered() into hw_breakpoint.c powerpc/ptrace: create ppc_gethwdinfo() powerpc/ptrace: create ptrace_get_debugreg() powerpc/ptrace: split out ADV_DEBUG_REGS related functions. powerpc/ptrace: move register viewing functions out of ptrace.c powerpc/ptrace: split out TRANSACTIONAL_MEM related functions. powerpc/ptrace: split out SPE related functions. powerpc/ptrace: split out ALTIVEC related functions. powerpc/ptrace: split out VSX related functions. powerpc/ptrace: drop PARAMETER_SAVE_AREA_OFFSET powerpc/ptrace: drop unnecessary #ifdefs CONFIG_PPC64 powerpc/ptrace: remove unused header includes ...
2020-03-25powerpc/kasan: Fix kasan_remap_early_shadow_ro()Christophe Leroy1-1/+1
At the moment kasan_remap_early_shadow_ro() does nothing, because k_end is 0 and k_cur < 0 is always true. Change the test to k_cur != k_end, as done in kasan_init_shadow_page_tables() Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Fixes: cbd18991e24f ("powerpc/mm: Fix an Oops in kasan_mmu_init()") Cc: stable@vger.kernel.org Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/4e7b56865e01569058914c991143f5961b5d4719.1583507333.git.christophe.leroy@c-s.fr
2020-03-13powerpc/kasan: Fix shadow memory protection with CONFIG_KASAN_VMALLOCChristophe Leroy1-7/+2
With CONFIG_KASAN_VMALLOC, new page tables are created at the time shadow memory for vmalloc area is unmapped. If some parts of the page table still have entries to the zero page shadow memory, the entries are wrongly marked RW. With CONFIG_KASAN_VMALLOC, almost the entire kernel address space is managed by KASAN. To make it simple, just create KASAN page tables for the entire kernel space at kasan_init(). That doesn't use much more space, and that's anyway already done for hash platforms. Fixes: 3d4247fcc938 ("powerpc/32: Add support of KASAN_VMALLOC") 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/ef5248fc1f496c6b0dfdb59380f24968f25f75c5.1583513368.git.christophe.leroy@c-s.fr
2020-03-10Merge branch 'fixes' into nextMichael Ellerman1-2/+1
Merge in our fixes branch. In particular we want to merge the TM and KUAP fixes, so we can add selftests for them in next.
2020-02-26powerpc/32: refactor pmd_offset(pud_offset(pgd_offset...Christophe Leroy1-4/+4
At several places pmd pointer is retrieved through the same action: pmd = pmd_offset(pud_offset(pgd_offset(mm, addr), addr), addr); or pmd = pmd_offset(pud_offset(pgd_offset_k(addr), addr), addr); Refactor this by implementing two helpers pmd_ptr() and pmd_ptr_k() This will help when adding the p4d level. 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/7b065c5be35726af4066cab238ee35cabceda1fa.1578558199.git.christophe.leroy@c-s.fr
2020-02-18powerpc/32s: Fix DSI and ISI exceptions for CONFIG_VMAP_STACKChristophe Leroy1-2/+1
hash_page() needs to read page tables from kernel memory. When entire kernel memory is mapped by BATs, which is normally the case when CONFIG_STRICT_KERNEL_RWX is not set, it works even if the page hosting the page table is not referenced in the MMU hash table. However, if the page where the page table resides is not covered by a BAT, a DSI fault can be encountered from hash_page(), and it loops forever. This can happen when CONFIG_STRICT_KERNEL_RWX is selected and the alignment of the different regions is too small to allow covering the entire memory with BATs. This also happens when CONFIG_DEBUG_PAGEALLOC is selected or when booting with 'nobats' flag. Also, if the page containing the kernel stack is not present in the MMU hash table, registers cannot be saved and a recursive DSI fault is encountered. To allow hash_page() to properly do its job at all time and load the MMU hash table whenever needed, it must run with data MMU disabled. This means it must be called before re-enabling data MMU. To allow this, registers clobbered by hash_page() and create_hpte() have to be saved in the thread struct together with SRR0, SSR1, DAR and DSISR. It is also necessary to ensure that DSI prolog doesn't overwrite regs saved by prolog of the current running exception. That means: - DSI can only use SPRN_SPRG_SCRATCH0 - Exceptions must free SPRN_SPRG_SCRATCH0 before writing to the stack. This also fixes the Oops reported by Erhard when create_hpte() is called by add_hash_page(). Due to prolog size increase, a few more exceptions had to get split in two parts. Fixes: cd08f109e262 ("powerpc/32s: Enable CONFIG_VMAP_STACK") Reported-by: Erhard F. <erhard_f@mailbox.org> Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Tested-by: Erhard F. <erhard_f@mailbox.org> Tested-by: Larry Finger <Larry.Finger@lwfinger.net> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://bugzilla.kernel.org/show_bug.cgi?id=206501 Link: https://lore.kernel.org/r/64a4aa44686e9fd4b01333401367029771d9b231.1581761633.git.christophe.leroy@c-s.fr
2020-01-30powerpc/32s: Fix kasan_early_hash_table() for CONFIG_VMAP_STACKChristophe Leroy1-2/+5
On book3s/32 CPUs that are handling MMU through a hash table, MMU_init_hw() function was adapted for VMAP_STACK in order to handle virtual addresses instead of physical addresses in the low level hash functions. When using KASAN, the same adaptations are required for the early hash table set up by kasan_early_hash_table() function. Fixes: cd08f109e262 ("powerpc/32s: Enable CONFIG_VMAP_STACK") 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/fc8390a33c2a470105f01abbcbdc7916c30c0a54.1580301269.git.christophe.leroy@c-s.fr
2020-01-27powerpc/32: Reuse orphaned memblocks in kasan_init_shadow_page_tables()Christophe Leroy1-3/+3
If concurrent PMD population has happened, re-use orphaned memblocks. 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/b29ffffb9206dc14541fa420c17604240728041b.1579024426.git.christophe.leroy@c-s.fr
2020-01-27powerpc/32: Simplify KASAN initChristophe Leroy1-21/+5
Since kasan_init_region() is not used anymore for modules, KASAN init is done while slab_is_available() is false. 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/84b27bf08b41c8343efd88e10f2eccd8e9f85593.1579024426.git.christophe.leroy@c-s.fr
2020-01-27powerpc/32: Force KASAN_VMALLOC for modulesChristophe Leroy1-26/+5
Unloading/Reloading of modules seems to fail with KASAN_VMALLOC but works properly with it. Force selection of KASAN_VMALLOC when MODULES are selected, and drop module_alloc() which was dedicated to KASAN for modules. Reported-by: <erhard_f@mailbox.org> Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://bugzilla.kernel.org/show_bug.cgi?id=205283 Link: https://lore.kernel.org/r/f909da11aecb59ab7f32ba01fae6f356eaa4d7bc.1579024426.git.christophe.leroy@c-s.fr
2020-01-27powerpc/32: Add support of KASAN_VMALLOCChristophe Leroy1-1/+32
Add support of KASAN_VMALLOC on PPC32. To allow this, the early shadow covering the VMALLOC space need to be removed once high_memory var is set and before freeing memblock. And the VMALLOC area need to be aligned such that boundaries are covered by a full shadow page. 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/031dec5487bde9b2181c8b3c9800e1879cf98c1a.1579024426.git.christophe.leroy@c-s.fr
2019-09-21powerpc/mm: Fix an Oops in kasan_mmu_init()Christophe Leroy1-1/+14
Uncompressing Kernel Image ... OK Loading Device Tree to 01ff7000, end 01fff74f ... OK [ 0.000000] printk: bootconsole [udbg0] enabled [ 0.000000] BUG: Unable to handle kernel data access at 0xf818c000 [ 0.000000] Faulting instruction address: 0xc0013c7c [ 0.000000] Thread overran stack, or stack corrupted [ 0.000000] Oops: Kernel access of bad area, sig: 11 [#1] [ 0.000000] BE PAGE_SIZE=16K PREEMPT [ 0.000000] Modules linked in: [ 0.000000] CPU: 0 PID: 0 Comm: swapper Not tainted 5.3.0-rc4-s3k-dev-00743-g5abe4a3e8fd3-dirty #2080 [ 0.000000] NIP: c0013c7c LR: c0013310 CTR: 00000000 [ 0.000000] REGS: c0c5ff38 TRAP: 0300 Not tainted (5.3.0-rc4-s3k-dev-00743-g5abe4a3e8fd3-dirty) [ 0.000000] MSR: 00001032 <ME,IR,DR,RI> CR: 99033955 XER: 80002100 [ 0.000000] DAR: f818c000 DSISR: 82000000 [ 0.000000] GPR00: c0013310 c0c5fff0 c0ad6ac0 c0c600c0 f818c031 82000000 00000000 ffffffff [ 0.000000] GPR08: 00000000 f1f1f1f1 c0013c2c c0013304 99033955 00400008 00000000 07ff9598 [ 0.000000] GPR16: 00000000 07ffb94c 00000000 00000000 00000000 00000000 00000000 f818cfb2 [ 0.000000] GPR24: 00000000 00000000 00001000 ffffffff 00000000 c07dbf80 00000000 f818c000 [ 0.000000] NIP [c0013c7c] do_page_fault+0x50/0x904 [ 0.000000] LR [c0013310] handle_page_fault+0xc/0x38 [ 0.000000] Call Trace: [ 0.000000] Instruction dump: [ 0.000000] be010080 91410014 553fe8fe 3d40c001 3d20f1f1 7d800026 394a3c2c 3fffe000 [ 0.000000] 6129f1f1 900100c4 9181007c 91410018 <913f0000> 3d2001f4 6129f4f4 913f0004 Don't map the early shadow page read-only yet when creating the new page tables for the real shadow memory, otherwise the memblock allocations that immediately follows to create the real shadow pages that are about to replace the early shadow page trigger a page fault if they fall into the region being worked on at the moment. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Fixes: 2edb16efc899 ("powerpc/32: Add KASAN support") Cc: stable@vger.kernel.org Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/fe86886fb8db44360417cee0dc515ad47ca6ef72.1566382750.git.christophe.leroy@c-s.fr
2019-09-21powerpc/mm: Add a helper to select PAGE_KERNEL_RO or PAGE_READONLYChristophe Leroy1-8/+13
In a couple of places there is a need to select whether read-only protection of shadow pages is performed with PAGE_KERNEL_RO or with PAGE_READONLY. Add a helper to avoid duplicating the choice. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Cc: stable@vger.kernel.org Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/9f33f44b9cd741c4a02b3dce7b8ef9438fe2cd2a.1566382750.git.christophe.leroy@c-s.fr
2019-08-20powerpc/kasan: Fix shadow area set up for modules.Christophe Leroy1-1/+1
When loading modules, from time to time an Oops is encountered during the init of shadow area for globals. This is due to the last page not always being mapped depending on the exact distance between the start and the end of the shadow area and the alignment with the page addresses. Fix this by aligning the starting address with the page address. Fixes: 2edb16efc899 ("powerpc/32: Add KASAN support") Cc: stable@vger.kernel.org # v5.2+ Reported-by: Erhard F. <erhard_f@mailbox.org> 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/4f887e9b77d0d725cbb52035c7ece485c1c5fc14.1565361881.git.christophe.leroy@c-s.fr
2019-08-20powerpc/kasan: Fix parallel loading of modules.Christophe Leroy1-2/+19
Parallel loading of modules may lead to bad setup of shadow page table entries. First, lets align modules so that two modules never share the same shadow page. Second, ensure that two modules cannot allocate two page tables for the same PMD entry at the same time. This is done by using init_mm.page_table_lock in the same way as __pte_alloc_kernel() Fixes: 2edb16efc899 ("powerpc/32: Add KASAN support") Cc: stable@vger.kernel.org # v5.2+ 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/c97284f912128cbc3f2fe09d68e90e65fb3e6026.1565361876.git.christophe.leroy@c-s.fr
2019-07-31powerpc/kasan: fix early boot failure on PPC32Christophe Leroy1-2/+5
Due to commit 4a6d8cf90017 ("powerpc/mm: don't use pte_alloc_kernel() until slab is available on PPC32"), pte_alloc_kernel() cannot be used during early KASAN init. Fix it by using memblock_alloc() instead. Fixes: 2edb16efc899 ("powerpc/32: Add KASAN support") Cc: stable@vger.kernel.org # v5.2+ Reported-by: Erhard F. <erhard_f@mailbox.org> 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/da89670093651437f27d2975224712e0a130b055.1564552796.git.christophe.leroy@c-s.fr
2019-05-06powerpc/kasan: add missing/lost MakefileChristophe Leroy1-0/+5
For unknown reason (aka. mpe is a doofus), the new Makefile added via the KASAN support patch didn't land into arch/powerpc/mm/kasan/ This patch restores it. Fixes: 2edb16efc899 ("powerpc/32: Add KASAN support") Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-05-02powerpc/32s: map kasan zero shadow with PAGE_READONLY instead of PAGE_KERNEL_ROChristophe Leroy1-2/+8
For hash32, the zero shadow page gets mapped with PAGE_READONLY instead of PAGE_KERNEL_RO, because the PP bits don't provide a RO kernel, so PAGE_KERNEL_RO is equivalent to PAGE_KERNEL. By using PAGE_READONLY, the page is RO for both kernel and user, but this is not a security issue as it contains only zeroes. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-05-02powerpc/32s: set up an early static hash table for KASAN.Christophe Leroy1-1/+22
KASAN requires early activation of hash table, before memblock() functions are available. This patch implements an early hash_table statically defined in __initdata. During early boot, a single page table is used. For hash32, when doing the final init, one page table is allocated for each PGD entry because of the _PAGE_HASHPTE flag which can't be common to several virt pages. This is done after memblock get available but before switching to the final hash table, otherwise there are issues with TLB flushing due to the shared entries. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-05-02powerpc/32: Add KASAN supportChristophe Leroy1-0/+156
This patch adds KASAN support for PPC32. The following patch will add an early activation of hash table for book3s. Until then, a warning will be raised if trying to use KASAN on an hash 6xx. To support KASAN, this patch initialises that MMU mapings for accessing to the KASAN shadow area defined in a previous patch. An early mapping is set as soon as the kernel code has been relocated at its definitive place. Then the definitive mapping is set once paging is initialised. For modules, the shadow area is allocated at module_alloc(). Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>