linux.git/arch/powerpc, branch vm-bind

mmu_gather: Remove per arch tlb_{start,end}_vma()

2022-07-21T17:50:13+00:00

Scattered across the archs are 3 basic forms of tlb_{start,end}_vma(). Provide two new MMU_GATHER_knobs to enumerate them and remove the per arch tlb_{start,end}_vma() implementations. - MMU_GATHER_NO_FLUSH_CACHE indicates the arch has flush_cache_range() but does *NOT* want to call it for each VMA. - MMU_GATHER_MERGE_VMAS indicates the arch wants to merge the invalidate across multiple VMAs if possible. With these it is possible to capture the three forms: 1) empty stubs; select MMU_GATHER_NO_FLUSH_CACHE and MMU_GATHER_MERGE_VMAS 2) start: flush_cache_range(), end: empty; select MMU_GATHER_MERGE_VMAS 3) start: flush_cache_range(), end: flush_tlb_range(); default Obviously, if the architecture does not have flush_cache_range() then it also doesn't need to select MMU_GATHER_NO_FLUSH_CACHE. Signed-off-by: Peter Zijlstra (Intel) Acked-by: Will Deacon Cc: David Miller Signed-off-by: Linus Torvalds

powerpc/powernv: delay rng platform device creation until later in boot

2022-07-04T11:11:47+00:00

The platform device for the rng must be created much later in boot. Otherwise it tries to connect to a parent that doesn't yet exist, resulting in this splat: [ 0.000478] kobject: '(null)' ((____ptrval____)): is not initialized, yet kobject_get() is being called. [ 0.002925] [c000000002a0fb30] [c00000000073b0bc] kobject_get+0x8c/0x100 (unreliable) [ 0.003071] [c000000002a0fba0] [c00000000087e464] device_add+0xf4/0xb00 [ 0.003194] [c000000002a0fc80] [c000000000a7f6e4] of_device_add+0x64/0x80 [ 0.003321] [c000000002a0fcb0] [c000000000a800d0] of_platform_device_create_pdata+0xd0/0x1b0 [ 0.003476] [c000000002a0fd00] [c00000000201fa44] pnv_get_random_long_early+0x240/0x2e4 [ 0.003623] [c000000002a0fe20] [c000000002060c38] random_init+0xc0/0x214 This patch fixes the issue by doing the platform device creation inside of machine_subsys_initcall. Fixes: f3eac426657d ("powerpc/powernv: wire up rng during setup_arch") Cc: stable@vger.kernel.org Reported-by: Sachin Sant Signed-off-by: Jason A. Donenfeld Tested-by: Sachin Sant [mpe: Change "of node" to "platform device" in change log] Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20220630121654.1939181-1-Jason@zx2c4.com

powerpc/memhotplug: Add add_pages override for PPC

2022-06-29T10:43:16+00:00

With commit ffa0b64e3be5 ("powerpc: Fix virt_addr_valid() for 64-bit Book3E & 32-bit") the kernel now validate the addr against high_memory value. This results in the below BUG_ON with dax pfns. [ 635.798741][T26531] kernel BUG at mm/page_alloc.c:5521! 1:mon> e cpu 0x1: Vector: 700 (Program Check) at [c000000007287630] pc: c00000000055ed48: free_pages.part.0+0x48/0x110 lr: c00000000053ca70: tlb_finish_mmu+0x80/0xd0 sp: c0000000072878d0 msr: 800000000282b033 current = 0xc00000000afabe00 paca = 0xc00000037ffff300 irqmask: 0x03 irq_happened: 0x05 pid = 26531, comm = 50-landscape-sy kernel BUG at :5521! Linux version 5.19.0-rc3-14659-g4ec05be7c2e1 (kvaneesh@ltc-boston8) (gcc (Ubuntu 9.4.0-1ubuntu1~20.04.1) 9.4.0, GNU ld (GNU Binutils for Ubuntu) 2.34) #625 SMP Thu Jun 23 00:35:43 CDT 2022 1:mon> t [link register ] c00000000053ca70 tlb_finish_mmu+0x80/0xd0 [c0000000072878d0] c00000000053ca54 tlb_finish_mmu+0x64/0xd0 (unreliable) [c000000007287900] c000000000539424 exit_mmap+0xe4/0x2a0 [c0000000072879e0] c00000000019fc1c mmput+0xcc/0x210 [c000000007287a20] c000000000629230 begin_new_exec+0x5e0/0xf40 [c000000007287ae0] c00000000070b3cc load_elf_binary+0x3ac/0x1e00 [c000000007287c10] c000000000627af0 bprm_execve+0x3b0/0xaf0 [c000000007287cd0] c000000000628414 do_execveat_common.isra.0+0x1e4/0x310 [c000000007287d80] c00000000062858c sys_execve+0x4c/0x60 [c000000007287db0] c00000000002c1b0 system_call_exception+0x160/0x2c0 [c000000007287e10] c00000000000c53c system_call_common+0xec/0x250 The fix is to make sure we update high_memory on memory hotplug. This is similar to what x86 does in commit 3072e413e305 ("mm/memory_hotplug: introduce add_pages") Fixes: ffa0b64e3be5 ("powerpc: Fix virt_addr_valid() for 64-bit Book3E & 32-bit") Signed-off-by: Aneesh Kumar K.V Reviewed-by: Kefeng Wang Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20220629050925.31447-1-aneesh.kumar@linux.ibm.com

powerpc/bpf: Fix use of user_pt_regs in uapi

2022-06-29T10:43:04+00:00

Trying to build a .c file that includes : $ cat test_bpf_headers.c #include throws the below error: /usr/include/linux/bpf_perf_event.h:14:28: error: field ‘regs’ has incomplete type 14 | bpf_user_pt_regs_t regs; | ^~~~ This is because we typedef bpf_user_pt_regs_t to 'struct user_pt_regs' in arch/powerpc/include/uaps/asm/bpf_perf_event.h, but 'struct user_pt_regs' is not exposed to userspace. Powerpc has both pt_regs and user_pt_regs structures. However, unlike arm64 and s390, we expose user_pt_regs to userspace as just 'pt_regs'. As such, we should typedef bpf_user_pt_regs_t to 'struct pt_regs' for userspace. Within the kernel though, we want to typedef bpf_user_pt_regs_t to 'struct user_pt_regs'. Remove arch/powerpc/include/uapi/asm/bpf_perf_event.h so that the uapi/asm-generic version of the header is exposed to userspace. Introduce arch/powerpc/include/asm/bpf_perf_event.h so that we can typedef bpf_user_pt_regs_t to 'struct user_pt_regs' for use within the kernel. Note that this was not showing up with the bpf selftest build since tools/include/uapi/asm/bpf_perf_event.h didn't include the powerpc variant. Fixes: a6460b03f945ee ("powerpc/bpf: Fix broken uapi for BPF_PROG_TYPE_PERF_EVENT") Cc: stable@vger.kernel.org # v4.20+ Signed-off-by: Naveen N. Rao [mpe: Use typical naming for header include guard] Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20220627191119.142867-1-naveen.n.rao@linux.vnet.ibm.com

powerpc/prom_init: Fix kernel config grep

2022-06-24T03:47:26+00:00

When searching for config options, use the KCONFIG_CONFIG shell variable so that builds using non-standard config locations work. Fixes: 26deb04342e3 ("powerpc: prepare string/mem functions for KASAN") Cc: stable@vger.kernel.org # v5.2+ Signed-off-by: Liam R. Howlett Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20220624011745.4060795-1-Liam.Howlett@oracle.com

powerpc/book3e: Fix PUD allocation size in map_kernel_page()

2022-06-24T02:42:45+00:00

Commit 2fb4706057bc ("powerpc: add support for folded p4d page tables") erroneously changed PUD setup to a mix of PMD and PUD. Fix it. While at it, use PTE_TABLE_SIZE instead of PAGE_SIZE for PTE tables in order to avoid any confusion. Fixes: 2fb4706057bc ("powerpc: add support for folded p4d page tables") Cc: stable@vger.kernel.org # v5.8+ Signed-off-by: Christophe Leroy Acked-by: Mike Rapoport Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/95ddfd6176d53e6c85e13bd1c358359daa56775f.1655974558.git.christophe.leroy@csgroup.eu

powerpc/xive/spapr: correct bitmap allocation size

2022-06-24T02:40:38+00:00

kasan detects access beyond the end of the xibm->bitmap allocation: BUG: KASAN: slab-out-of-bounds in _find_first_zero_bit+0x40/0x140 Read of size 8 at addr c00000001d1d0118 by task swapper/0/1 CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.19.0-rc2-00001-g90df023b36dd #28 Call Trace: [c00000001d98f770] [c0000000012baab8] dump_stack_lvl+0xac/0x108 (unreliable) [c00000001d98f7b0] [c00000000068faac] print_report+0x37c/0x710 [c00000001d98f880] [c0000000006902c0] kasan_report+0x110/0x354 [c00000001d98f950] [c000000000692324] __asan_load8+0xa4/0xe0 [c00000001d98f970] [c0000000011c6ed0] _find_first_zero_bit+0x40/0x140 [c00000001d98f9b0] [c0000000000dbfbc] xive_spapr_get_ipi+0xcc/0x260 [c00000001d98fa70] [c0000000000d6d28] xive_setup_cpu_ipi+0x1e8/0x450 [c00000001d98fb30] [c000000004032a20] pSeries_smp_probe+0x5c/0x118 [c00000001d98fb60] [c000000004018b44] smp_prepare_cpus+0x944/0x9ac [c00000001d98fc90] [c000000004009f9c] kernel_init_freeable+0x2d4/0x640 [c00000001d98fd90] [c0000000000131e8] kernel_init+0x28/0x1d0 [c00000001d98fe10] [c00000000000cd54] ret_from_kernel_thread+0x5c/0x64 Allocated by task 0: kasan_save_stack+0x34/0x70 __kasan_kmalloc+0xb4/0xf0 __kmalloc+0x268/0x540 xive_spapr_init+0x4d0/0x77c pseries_init_irq+0x40/0x27c init_IRQ+0x44/0x84 start_kernel+0x2a4/0x538 start_here_common+0x1c/0x20 The buggy address belongs to the object at c00000001d1d0118 which belongs to the cache kmalloc-8 of size 8 The buggy address is located 0 bytes inside of 8-byte region [c00000001d1d0118, c00000001d1d0120) The buggy address belongs to the physical page: page:c00c000000074740 refcount:1 mapcount:0 mapping:0000000000000000 index:0xc00000001d1d0558 pfn:0x1d1d flags: 0x7ffff000000200(slab|node=0|zone=0|lastcpupid=0x7ffff) raw: 007ffff000000200 c00000001d0003c8 c00000001d0003c8 c00000001d010480 raw: c00000001d1d0558 0000000001e1000a 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: c00000001d1d0000: fc 00 fc fc fc fc fc fc fc fc fc fc fc fc fc fc c00000001d1d0080: fc fc 00 fc fc fc fc fc fc fc fc fc fc fc fc fc >c00000001d1d0100: fc fc fc 02 fc fc fc fc fc fc fc fc fc fc fc fc ^ c00000001d1d0180: fc fc fc fc 04 fc fc fc fc fc fc fc fc fc fc fc c00000001d1d0200: fc fc fc fc fc 04 fc fc fc fc fc fc fc fc fc fc This happens because the allocation uses the wrong unit (bits) when it should pass (BITS_TO_LONGS(count) * sizeof(long)) or equivalent. With small numbers of bits, the allocated object can be smaller than sizeof(long), which results in invalid accesses. Use bitmap_zalloc() to allocate and initialize the irq bitmap, paired with bitmap_free() for consistency. Signed-off-by: Nathan Lynch Reviewed-by: Cédric Le Goater Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20220623182509.3985625-1-nathanl@linux.ibm.com

powerpc/powernv: wire up rng during setup_arch

2022-06-22T09:47:22+00:00

The platform's RNG must be available before random_init() in order to be useful for initial seeding, which in turn means that it needs to be called from setup_arch(), rather than from an init call. Complicating things, however, is that POWER8 systems need some per-cpu state and kmalloc, which isn't available at this stage. So we split things up into an early phase and a later opportunistic phase. This commit also removes some noisy log messages that don't add much. Fixes: a4da0d50b2a0 ("powerpc: Implement arch_get_random_long/int() for powernv") Cc: stable@vger.kernel.org # v3.13+ Signed-off-by: Jason A. Donenfeld Reviewed-by: Christophe Leroy [mpe: Add of_node_put(), use pnv naming, minor change log editing] Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20220621140849.127227-1-Jason@zx2c4.com

powerpc/prom_init: Fix build failure with GCC_PLUGIN_STRUCTLEAK_BYREF_ALL and KASAN

2022-06-19T11:57:56+00:00

When CONFIG_KASAN is selected, we expect prom_init to use __memset() because it is too early to use memset(). But with CONFIG_GCC_PLUGIN_STRUCTLEAK_BYREF_ALL, the compiler adds calls to memset() to clear objects on stack, hence the following failure: PROMCHK arch/powerpc/kernel/prom_init_check Error: External symbol 'memset' referenced from prom_init.c make[2]: *** [arch/powerpc/kernel/Makefile:204 : arch/powerpc/kernel/prom_init_check] Erreur 1 prom_find_machine_type() is called from prom_init() and is called only once, so lets put compat[] in BSS instead of stack to avoid that. Signed-off-by: Christophe Leroy Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/3802811f7cf94f730be44688539c01bba3a3b5c0.1654875808.git.christophe.leroy@csgroup.eu

powerpc/rtas: Allow ibm,platform-dump RTAS call with null buffer address

2022-06-18T00:19:10+00:00

Add a special case to block_rtas_call() to allow the ibm,platform-dump RTAS call through the RTAS filter if the buffer address is 0. According to PAPR, ibm,platform-dump is called with a null buffer address to notify the platform firmware that processing of a particular dump is finished. Without this, on a pseries machine with CONFIG_PPC_RTAS_FILTER enabled, an application such as rtas_errd that is attempting to retrieve a dump will encounter an error at the end of the retrieval process. Fixes: bd59380c5ba4 ("powerpc/rtas: Restrict RTAS requests from userspace") Cc: stable@vger.kernel.org Reported-by: Sathvika Vasireddy Signed-off-by: Andrew Donnellan Reviewed-by: Tyrel Datwyler Reviewed-by: Nathan Lynch Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20220614134952.156010-1-ajd@linux.ibm.com