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2023-01-18powerpc/imc-pmu: Fix use of mutex in IRQs disabled sectionKajol Jain1-1/+1
commit 76d588dddc459fefa1da96e0a081a397c5c8e216 upstream. Current imc-pmu code triggers a WARNING with CONFIG_DEBUG_ATOMIC_SLEEP and CONFIG_PROVE_LOCKING enabled, while running a thread_imc event. Command to trigger the warning: # perf stat -e thread_imc/CPM_CS_FROM_L4_MEM_X_DPTEG/ sleep 5 Performance counter stats for 'sleep 5': 0 thread_imc/CPM_CS_FROM_L4_MEM_X_DPTEG/ 5.002117947 seconds time elapsed 0.000131000 seconds user 0.001063000 seconds sys Below is snippet of the warning in dmesg: BUG: sleeping function called from invalid context at kernel/locking/mutex.c:580 in_atomic(): 1, irqs_disabled(): 1, non_block: 0, pid: 2869, name: perf-exec preempt_count: 2, expected: 0 4 locks held by perf-exec/2869: #0: c00000004325c540 (&sig->cred_guard_mutex){+.+.}-{3:3}, at: bprm_execve+0x64/0xa90 #1: c00000004325c5d8 (&sig->exec_update_lock){++++}-{3:3}, at: begin_new_exec+0x460/0xef0 #2: c0000003fa99d4e0 (&cpuctx_lock){-...}-{2:2}, at: perf_event_exec+0x290/0x510 #3: c000000017ab8418 (&ctx->lock){....}-{2:2}, at: perf_event_exec+0x29c/0x510 irq event stamp: 4806 hardirqs last enabled at (4805): [<c000000000f65b94>] _raw_spin_unlock_irqrestore+0x94/0xd0 hardirqs last disabled at (4806): [<c0000000003fae44>] perf_event_exec+0x394/0x510 softirqs last enabled at (0): [<c00000000013c404>] copy_process+0xc34/0x1ff0 softirqs last disabled at (0): [<0000000000000000>] 0x0 CPU: 36 PID: 2869 Comm: perf-exec Not tainted 6.2.0-rc2-00011-g1247637727f2 #61 Hardware name: 8375-42A POWER9 0x4e1202 opal:v7.0-16-g9b85f7d961 PowerNV Call Trace: dump_stack_lvl+0x98/0xe0 (unreliable) __might_resched+0x2f8/0x310 __mutex_lock+0x6c/0x13f0 thread_imc_event_add+0xf4/0x1b0 event_sched_in+0xe0/0x210 merge_sched_in+0x1f0/0x600 visit_groups_merge.isra.92.constprop.166+0x2bc/0x6c0 ctx_flexible_sched_in+0xcc/0x140 ctx_sched_in+0x20c/0x2a0 ctx_resched+0x104/0x1c0 perf_event_exec+0x340/0x510 begin_new_exec+0x730/0xef0 load_elf_binary+0x3f8/0x1e10 ... do not call blocking ops when !TASK_RUNNING; state=2001 set at [<00000000fd63e7cf>] do_nanosleep+0x60/0x1a0 WARNING: CPU: 36 PID: 2869 at kernel/sched/core.c:9912 __might_sleep+0x9c/0xb0 CPU: 36 PID: 2869 Comm: sleep Tainted: G W 6.2.0-rc2-00011-g1247637727f2 #61 Hardware name: 8375-42A POWER9 0x4e1202 opal:v7.0-16-g9b85f7d961 PowerNV NIP: c000000000194a1c LR: c000000000194a18 CTR: c000000000a78670 REGS: c00000004d2134e0 TRAP: 0700 Tainted: G W (6.2.0-rc2-00011-g1247637727f2) MSR: 9000000000021033 <SF,HV,ME,IR,DR,RI,LE> CR: 48002824 XER: 00000000 CFAR: c00000000013fb64 IRQMASK: 1 The above warning triggered because the current imc-pmu code uses mutex lock in interrupt disabled sections. The function mutex_lock() internally calls __might_resched(), which will check if IRQs are disabled and in case IRQs are disabled, it will trigger the warning. Fix the issue by changing the mutex lock to spinlock. Fixes: 8f95faaac56c ("powerpc/powernv: Detect and create IMC device") Reported-by: Michael Petlan <mpetlan@redhat.com> Reported-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Kajol Jain <kjain@linux.ibm.com> [mpe: Fix comments, trim oops in change log, add reported-by tags] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20230106065157.182648-1-kjain@linux.ibm.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-07powerpc/bpf: Fix use of user_pt_regs in uapiNaveen N. Rao2-9/+9
commit b21bd5a4b130f8370861478d2880985daace5913 upstream. Trying to build a .c file that includes <linux/bpf_perf_event.h>: $ cat test_bpf_headers.c #include <linux/bpf_perf_event.h> 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 <naveen.n.rao@linux.vnet.ibm.com> [mpe: Use typical naming for header include guard] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20220627191119.142867-1-naveen.n.rao@linux.vnet.ibm.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-02powerpc/ftrace: Remove ftrace init tramp once kernel init is completeNaveen N. Rao1-1/+4
commit 84ade0a6655bee803d176525ef457175cbf4df22 upstream. Stop using the ftrace trampoline for init section once kernel init is complete. Fixes: 67361cf8071286 ("powerpc/ftrace: Handle large kernel configs") Cc: stable@vger.kernel.org # v4.20+ Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20220516071422.463738-1-naveen.n.rao@linux.vnet.ibm.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-06-22powerpc/mm: Switch obsolete dssall to .longAlexey Kardashevskiy1-0/+2
commit d51f86cfd8e378d4907958db77da3074f6dce3ba upstream. The dssall ("Data Stream Stop All") instruction is obsolete altogether with other Data Cache Instructions since ISA 2.03 (year 2006). LLVM IAS does not support it but PPC970 seems to be using it. This switches dssall to .long as there is no much point in fixing LLVM. Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20211221055904.555763-6-aik@ozlabs.ru [sudip: adjust context] Signed-off-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-06-22powerpc: define get_cycles macro for arch-overrideJason A. Donenfeld1-0/+1
commit 408835832158df0357e18e96da7f2d1ed6b80e7f upstream. PowerPC defines a get_cycles() function, but it does not do the usual `#define get_cycles get_cycles` dance, making it impossible for generic code to see if an arch-specific function was defined. While the get_cycles() ifdef is not currently used, the following timekeeping patch in this series will depend on the macro existing (or not existing) when defining random_get_entropy(). Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Benjamin Herrenschmidt <benh@ozlabs.org> Cc: Paul Mackerras <paulus@samba.org> Acked-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-06-22powerpc: Use bool in archrandom.hRichard Henderson1-8/+9
commit 98dcfce69729f9ce0fb14f96a39bbdba21429597 upstream. The generic interface uses bool not int; match that. Reviewed-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Richard Henderson <rth@twiddle.net> Signed-off-by: Mark Brown <broonie@kernel.org> Link: https://lore.kernel.org/r/20200110145422.49141-9-broonie@kernel.org Signed-off-by: Theodore Ts'o <tytso@mit.edu> Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-06-22powerpc: Remove arch_has_random, arch_has_random_seedRichard Henderson1-10/+0
commit cbac004995a0ce8453bdc555fab579e2bdb842a6 upstream. These symbols are currently part of the generic archrandom.h interface, but are currently unused and can be removed. Signed-off-by: Richard Henderson <rth@twiddle.net> Signed-off-by: Mark Brown <broonie@kernel.org> Link: https://lore.kernel.org/r/20200110145422.49141-3-broonie@kernel.org Signed-off-by: Theodore Ts'o <tytso@mit.edu> Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-06-14powerpc/64: Only WARN if __pa()/__va() called with bad addressesMichael Ellerman1-2/+5
[ Upstream commit c4bce84d0bd3f396f702d69be2e92bbd8af97583 ] We added checks to __pa() / __va() to ensure they're only called with appropriate addresses. But using BUG_ON() is too strong, it means virt_addr_valid() will BUG when DEBUG_VIRTUAL is enabled. Instead switch them to warnings, arm64 does the same. Fixes: 4dd7554a6456 ("powerpc/64: Add VIRTUAL_BUG_ON checks for __va and __pa addresses") Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20220406145802.538416-5-mpe@ellerman.id.au Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-04-20powerpc: Fix virt_addr_valid() for 64-bit Book3E & 32-bitKefeng Wang1-1/+5
[ Upstream commit ffa0b64e3be58519ae472ea29a1a1ad681e32f48 ] mpe: On 64-bit Book3E vmalloc space starts at 0x8000000000000000. Because of the way __pa() works we have: __pa(0x8000000000000000) == 0, and therefore virt_to_pfn(0x8000000000000000) == 0, and therefore virt_addr_valid(0x8000000000000000) == true Which is wrong, virt_addr_valid() should be false for vmalloc space. In fact all vmalloc addresses that alias with a valid PFN will return true from virt_addr_valid(). That can cause bugs with hardened usercopy as described below by Kefeng Wang: When running ethtool eth0 on 64-bit Book3E, a BUG occurred: usercopy: Kernel memory exposure attempt detected from SLUB object not in SLUB page?! (offset 0, size 1048)! kernel BUG at mm/usercopy.c:99 ... usercopy_abort+0x64/0xa0 (unreliable) __check_heap_object+0x168/0x190 __check_object_size+0x1a0/0x200 dev_ethtool+0x2494/0x2b20 dev_ioctl+0x5d0/0x770 sock_do_ioctl+0xf0/0x1d0 sock_ioctl+0x3ec/0x5a0 __se_sys_ioctl+0xf0/0x160 system_call_exception+0xfc/0x1f0 system_call_common+0xf8/0x200 The code shows below, data = vzalloc(array_size(gstrings.len, ETH_GSTRING_LEN)); copy_to_user(useraddr, data, gstrings.len * ETH_GSTRING_LEN)) The data is alloced by vmalloc(), virt_addr_valid(ptr) will return true on 64-bit Book3E, which leads to the panic. As commit 4dd7554a6456 ("powerpc/64: Add VIRTUAL_BUG_ON checks for __va and __pa addresses") does, make sure the virt addr above PAGE_OFFSET in the virt_addr_valid() for 64-bit, also add upper limit check to make sure the virt is below high_memory. Meanwhile, for 32-bit PAGE_OFFSET is the virtual address of the start of lowmem, high_memory is the upper low virtual address, the check is suitable for 32-bit, this will fix the issue mentioned in commit 602946ec2f90 ("powerpc: Set max_mapnr correctly") too. On 32-bit there is a similar problem with high memory, that was fixed in commit 602946ec2f90 ("powerpc: Set max_mapnr correctly"), but that commit breaks highmem and needs to be reverted. We can't easily fix __pa(), we have code that relies on its current behaviour. So for now add extra checks to virt_addr_valid(). For 64-bit Book3S the extra checks are not necessary, the combination of virt_to_pfn() and pfn_valid() should yield the correct result, but they are harmless. Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com> Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu> [mpe: Add additional change log detail] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20220406145802.538416-1-mpe@ellerman.id.au Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-04-15powerpc: Fix build errors with newer binutilsAnders Roxell2-8/+35
commit 8667d0d64dd1f84fd41b5897fd87fa9113ae05e3 upstream. Building tinyconfig with gcc (Debian 11.2.0-16) and assembler (Debian 2.37.90.20220207) the following build error shows up: {standard input}: Assembler messages: {standard input}:1190: Error: unrecognized opcode: `stbcix' {standard input}:1433: Error: unrecognized opcode: `lwzcix' {standard input}:1453: Error: unrecognized opcode: `stbcix' {standard input}:1460: Error: unrecognized opcode: `stwcix' {standard input}:1596: Error: unrecognized opcode: `stbcix' ... Rework to add assembler directives [1] around the instruction. Going through them one by one shows that the changes should be safe. Like __get_user_atomic_128_aligned() is only called in p9_hmi_special_emu(), which according to the name is specific to power9. And __raw_rm_read*() are only called in things that are powernv or book3s_hv specific. [1] https://sourceware.org/binutils/docs/as/PowerPC_002dPseudo.html#PowerPC_002dPseudo Cc: stable@vger.kernel.org Co-developed-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Anders Roxell <anders.roxell@linaro.org> Reviewed-by: Segher Boessenkool <segher@kernel.crashing.org> [mpe: Make commit subject more descriptive] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20220224162215.3406642-2-anders.roxell@linaro.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-11-17powerpc/security: Add a helper to query stf_barrier typeNaveen N. Rao1-0/+5
upstream commit 030905920f32e91a52794937f67434ac0b3ea41a Add a helper to return the stf_barrier type for the current processor. Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/3bd5d7f96ea1547991ac2ce3137dc2b220bae285.1633464148.git.naveen.n.rao@linux.vnet.ibm.com Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-11-17powerpc/lib: Add helper to check if offset is within conditional branch rangeNaveen N. Rao1-0/+1
upstream commit 4549c3ea3160fa8b3f37dfe2f957657bb265eda9 Add a helper to check if a given offset is within the branch range for a powerpc conditional branch instruction, and update some sites to use the new helper. Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu> Acked-by: Song Liu <songliubraving@fb.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/442b69a34ced32ca346a0d9a855f3f6cfdbbbd41.1633464148.git.naveen.n.rao@linux.vnet.ibm.com Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-09-22KVM: PPC: Book3S HV Nested: Reflect guest PMU in-use to L0 when guest SPRs ↵Nicholas Piggin1-0/+7
are live [ Upstream commit 1782663897945a5cf28e564ba5eed730098e9aa4 ] After the L1 saves its PMU SPRs but before loading the L2's PMU SPRs, switch the pmcregs_in_use field in the L1 lppaca to the value advertised by the L2 in its VPA. On the way out of the L2, set it back after saving the L2 PMU registers (if they were in-use). This transfers the PMU liveness indication between the L1 and L2 at the points where the registers are not live. This fixes the nested HV bug for which a workaround was added to the L0 HV by commit 63279eeb7f93a ("KVM: PPC: Book3S HV: Always save guest pmu for guest capable of nesting"), which explains the problem in detail. That workaround is no longer required for guests that include this bug fix. Fixes: 360cae313702 ("KVM: PPC: Book3S HV: Nested guest entry via hypercall") Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Reviewed-by: Fabiano Rosas <farosas@linux.ibm.com> Link: https://lore.kernel.org/r/20210811160134.904987-10-npiggin@gmail.com Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-07-20powerpc/ps3: Add dma_mask to ps3_dma_regionGeoff Levand1-0/+2
[ Upstream commit 9733862e50fdba55e7f1554e4286fcc5302ff28e ] Commit f959dcd6ddfd29235030e8026471ac1b022ad2b0 (dma-direct: Fix potential NULL pointer dereference) added a null check on the dma_mask pointer of the kernel's device structure. Add a dma_mask variable to the ps3_dma_region structure and set the device structure's dma_mask pointer to point to this new variable. Fixes runtime errors like these: # WARNING: Fixes tag on line 10 doesn't match correct format # WARNING: Fixes tag on line 10 doesn't match correct format ps3_system_bus_match:349: dev=8.0(sb_01), drv=8.0(ps3flash): match WARNING: CPU: 0 PID: 1 at kernel/dma/mapping.c:151 .dma_map_page_attrs+0x34/0x1e0 ps3flash sb_01: ps3stor_setup:193: map DMA region failed Signed-off-by: Geoff Levand <geoff@infradead.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/562d0c9ea0100a30c3b186bcc7adb34b0bbd2cd7.1622746428.git.geoff@infradead.org Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-07-19powerpc/barrier: Avoid collision with clang's __lwsync macroNathan Chancellor1-0/+2
commit 015d98149b326e0f1f02e44413112ca8b4330543 upstream. A change in clang 13 results in the __lwsync macro being defined as __builtin_ppc_lwsync, which emits 'lwsync' or 'msync' depending on what the target supports. This breaks the build because of -Werror in arch/powerpc, along with thousands of warnings: In file included from arch/powerpc/kernel/pmc.c:12: In file included from include/linux/bug.h:5: In file included from arch/powerpc/include/asm/bug.h:109: In file included from include/asm-generic/bug.h:20: In file included from include/linux/kernel.h:12: In file included from include/linux/bitops.h:32: In file included from arch/powerpc/include/asm/bitops.h:62: arch/powerpc/include/asm/barrier.h:49:9: error: '__lwsync' macro redefined [-Werror,-Wmacro-redefined] #define __lwsync() __asm__ __volatile__ (stringify_in_c(LWSYNC) : : :"memory") ^ <built-in>:308:9: note: previous definition is here #define __lwsync __builtin_ppc_lwsync ^ 1 error generated. Undefine this macro so that the runtime patching introduced by commit 2d1b2027626d ("powerpc: Fixup lwsync at runtime") continues to work properly with clang and the build no longer breaks. Cc: stable@vger.kernel.org Signed-off-by: Nathan Chancellor <nathan@kernel.org> Reviewed-by: Nick Desaulniers <ndesaulniers@google.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://github.com/ClangBuiltLinux/linux/issues/1386 Link: https://github.com/llvm/llvm-project/commit/62b5df7fe2b3fda1772befeda15598fbef96a614 Link: https://lore.kernel.org/r/20210528182752.1852002-1-nathan@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-07-14KVM: PPC: Book3S HV: Fix TLB management on SMT8 POWER9 and POWER10 processorsSuraj Jitindar Singh1-0/+30
[ Upstream commit 77bbbc0cf84834ed130838f7ac1988567f4d0288 ] The POWER9 vCPU TLB management code assumes all threads in a core share a TLB, and that TLBIEL execued by one thread will invalidate TLBs for all threads. This is not the case for SMT8 capable POWER9 and POWER10 (big core) processors, where the TLB is split between groups of threads. This results in TLB multi-hits, random data corruption, etc. Fix this by introducing cpu_first_tlb_thread_sibling etc., to determine which siblings share TLBs, and use that in the guest TLB flushing code. [npiggin@gmail.com: add changelog and comment] Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Reviewed-by: Fabiano Rosas <farosas@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20210602040441.3984352-1-npiggin@gmail.com Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-05-14powerpc/64s: Fix pte update for kernel memory on radixJordan Niethe1-2/+4
[ Upstream commit b8b2f37cf632434456182e9002d63cbc4cccc50c ] When adding a PTE a ptesync is needed to order the update of the PTE with subsequent accesses otherwise a spurious fault may be raised. radix__set_pte_at() does not do this for performance gains. For non-kernel memory this is not an issue as any faults of this kind are corrected by the page fault handler. For kernel memory these faults are not handled. The current solution is that there is a ptesync in flush_cache_vmap() which should be called when mapping from the vmalloc region. However, map_kernel_page() does not call flush_cache_vmap(). This is troublesome in particular for code patching with Strict RWX on radix. In do_patch_instruction() the page frame that contains the instruction to be patched is mapped and then immediately patched. With no ordering or synchronization between setting up the PTE and writing to the page it is possible for faults. As the code patching is done using __put_user_asm_goto() the resulting fault is obscured - but using a normal store instead it can be seen: BUG: Unable to handle kernel data access on write at 0xc008000008f24a3c Faulting instruction address: 0xc00000000008bd74 Oops: Kernel access of bad area, sig: 11 [#1] LE PAGE_SIZE=64K MMU=Radix SMP NR_CPUS=2048 NUMA PowerNV Modules linked in: nop_module(PO+) [last unloaded: nop_module] CPU: 4 PID: 757 Comm: sh Tainted: P O 5.10.0-rc5-01361-ge3c1b78c8440-dirty #43 NIP: c00000000008bd74 LR: c00000000008bd50 CTR: c000000000025810 REGS: c000000016f634a0 TRAP: 0300 Tainted: P O (5.10.0-rc5-01361-ge3c1b78c8440-dirty) MSR: 9000000000009033 <SF,HV,EE,ME,IR,DR,RI,LE> CR: 44002884 XER: 00000000 CFAR: c00000000007c68c DAR: c008000008f24a3c DSISR: 42000000 IRQMASK: 1 This results in the kind of issue reported here: https://lore.kernel.org/linuxppc-dev/15AC5B0E-A221-4B8C-9039-FA96B8EF7C88@lca.pw/ Chris Riedl suggested a reliable way to reproduce the issue: $ mount -t debugfs none /sys/kernel/debug $ (while true; do echo function > /sys/kernel/debug/tracing/current_tracer ; echo nop > /sys/kernel/debug/tracing/current_tracer ; done) & Turning ftrace on and off does a large amount of code patching which in usually less then 5min will crash giving a trace like: ftrace-powerpc: (____ptrval____): replaced (4b473b11) != old (60000000) ------------[ ftrace bug ]------------ ftrace failed to modify [<c000000000bf8e5c>] napi_busy_loop+0xc/0x390 actual: 11:3b:47:4b Setting ftrace call site to call ftrace function ftrace record flags: 80000001 (1) expected tramp: c00000000006c96c ------------[ cut here ]------------ WARNING: CPU: 4 PID: 809 at kernel/trace/ftrace.c:2065 ftrace_bug+0x28c/0x2e8 Modules linked in: nop_module(PO-) [last unloaded: nop_module] CPU: 4 PID: 809 Comm: sh Tainted: P O 5.10.0-rc5-01360-gf878ccaf250a #1 NIP: c00000000024f334 LR: c00000000024f330 CTR: c0000000001a5af0 REGS: c000000004c8b760 TRAP: 0700 Tainted: P O (5.10.0-rc5-01360-gf878ccaf250a) MSR: 900000000282b033 <SF,HV,VEC,VSX,EE,FP,ME,IR,DR,RI,LE> CR: 28008848 XER: 20040000 CFAR: c0000000001a9c98 IRQMASK: 0 GPR00: c00000000024f330 c000000004c8b9f0 c000000002770600 0000000000000022 GPR04: 00000000ffff7fff c000000004c8b6d0 0000000000000027 c0000007fe9bcdd8 GPR08: 0000000000000023 ffffffffffffffd8 0000000000000027 c000000002613118 GPR12: 0000000000008000 c0000007fffdca00 0000000000000000 0000000000000000 GPR16: 0000000023ec37c5 0000000000000000 0000000000000000 0000000000000008 GPR20: c000000004c8bc90 c0000000027a2d20 c000000004c8bcd0 c000000002612fe8 GPR24: 0000000000000038 0000000000000030 0000000000000028 0000000000000020 GPR28: c000000000ff1b68 c000000000bf8e5c c00000000312f700 c000000000fbb9b0 NIP ftrace_bug+0x28c/0x2e8 LR ftrace_bug+0x288/0x2e8 Call Trace: ftrace_bug+0x288/0x2e8 (unreliable) ftrace_modify_all_code+0x168/0x210 arch_ftrace_update_code+0x18/0x30 ftrace_run_update_code+0x44/0xc0 ftrace_startup+0xf8/0x1c0 register_ftrace_function+0x4c/0xc0 function_trace_init+0x80/0xb0 tracing_set_tracer+0x2a4/0x4f0 tracing_set_trace_write+0xd4/0x130 vfs_write+0xf0/0x330 ksys_write+0x84/0x140 system_call_exception+0x14c/0x230 system_call_common+0xf0/0x27c To fix this when updating kernel memory PTEs using ptesync. Fixes: f1cb8f9beba8 ("powerpc/64s/radix: avoid ptesync after set_pte and ptep_set_access_flags") Signed-off-by: Jordan Niethe <jniethe5@gmail.com> Reviewed-by: Nicholas Piggin <npiggin@gmail.com> [mpe: Tidy up change log slightly] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20210208032957.1232102-1-jniethe5@gmail.com Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-05-11powerpc: fix EDEADLOCK redefinition error in uapi/asm/errno.hTony Ambardar1-0/+1
commit 7de21e679e6a789f3729e8402bc440b623a28eae upstream. A few archs like powerpc have different errno.h values for macros EDEADLOCK and EDEADLK. In code including both libc and linux versions of errno.h, this can result in multiple definitions of EDEADLOCK in the include chain. Definitions to the same value (e.g. seen with mips) do not raise warnings, but on powerpc there are redefinitions changing the value, which raise warnings and errors (if using "-Werror"). Guard against these redefinitions to avoid build errors like the following, first seen cross-compiling libbpf v5.8.9 for powerpc using GCC 8.4.0 with musl 1.1.24: In file included from ../../arch/powerpc/include/uapi/asm/errno.h:5, from ../../include/linux/err.h:8, from libbpf.c:29: ../../include/uapi/asm-generic/errno.h:40: error: "EDEADLOCK" redefined [-Werror] #define EDEADLOCK EDEADLK In file included from toolchain-powerpc_8540_gcc-8.4.0_musl/include/errno.h:10, from libbpf.c:26: toolchain-powerpc_8540_gcc-8.4.0_musl/include/bits/errno.h:58: note: this is the location of the previous definition #define EDEADLOCK 58 cc1: all warnings being treated as errors Cc: Stable <stable@vger.kernel.org> Reported-by: Rosen Penev <rosenp@gmail.com> Signed-off-by: Tony Ambardar <Tony.Ambardar@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200917135437.1238787-1-Tony.Ambardar@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-04-07powerpc: Force inlining of cpu_has_feature() to avoid build failureChristophe Leroy1-2/+2
[ Upstream commit eed5fae00593ab9d261a0c1ffc1bdb786a87a55a ] The code relies on constant folding of cpu_has_feature() based on possible and always true values as defined per CPU_FTRS_ALWAYS and CPU_FTRS_POSSIBLE. Build failure is encountered with for instance book3e_all_defconfig on kisskb in the AMDGPU driver which uses cpu_has_feature(CPU_FTR_VSX_COMP) to decide whether calling kernel_enable_vsx() or not. The failure is due to cpu_has_feature() not being inlined with that configuration with gcc 4.9. In the same way as commit acdad8fb4a15 ("powerpc: Force inlining of mmu_has_feature to fix build failure"), for inlining of cpu_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/b231dfa040ce4cc37f702f5c3a595fdeabfe0462.1615378209.git.christophe.leroy@csgroup.eu Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-03-30powerpc/4xx: Fix build errors from mfdcr()Michael Ellerman1-4/+4
[ Upstream commit eead089311f4d935ab5d1d8fbb0c42ad44699ada ] lkp reported a build error in fsp2.o: CC arch/powerpc/platforms/44x/fsp2.o {standard input}:577: Error: unsupported relocation against base Which comes from: pr_err("GESR0: 0x%08x\n", mfdcr(base + PLB4OPB_GESR0)); Where our mfdcr() macro is stringifying "base + PLB4OPB_GESR0", and passing that to the assembler, which obviously doesn't work. The mfdcr() macro already checks that the argument is constant using __builtin_constant_p(), and if not calls the out-of-line version of mfdcr(). But in this case GCC is smart enough to notice that "base + PLB4OPB_GESR0" will be constant, even though it's not something we can immediately stringify into a register number. Segher pointed out that passing the register number to the inline asm as a constant would be better, and in fact it fixes the build error, presumably because it gives GCC a chance to resolve the value. While we're at it, change mtdcr() similarly. Reported-by: kernel test robot <lkp@intel.com> Suggested-by: Segher Boessenkool <segher@kernel.crashing.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Acked-by: Feng Tang <feng.tang@intel.com> Link: https://lore.kernel.org/r/20210218123058.748882-1-mpe@ellerman.id.au Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-03-17powerpc/64s: Fix instruction encoding for lis in ppc_function_entry()Naveen N. Rao1-1/+1
commit cea15316ceee2d4a51dfdecd79e08a438135416c upstream. 'lis r2,N' is 'addis r2,0,N' and the instruction encoding in the macro LIS_R2 is incorrect (it currently maps to 'addis r0,r2,N'). Fix the same. Fixes: c71b7eff426f ("powerpc: Add ABIv2 support to ppc_function_entry") Cc: stable@vger.kernel.org # v3.16+ Reported-by: Jiri Olsa <jolsa@redhat.com> Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Acked-by: Segher Boessenkool <segher@kernel.crashing.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20210304020411.16796-1-naveen.n.rao@linux.vnet.ibm.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-17powerpc/64: Fix stack trace not displaying final frameMichael Ellerman1-0/+3
[ Upstream commit e3de1e291fa58a1ab0f471a4b458eff2514e4b5f ] In commit bf13718bc57a ("powerpc: show registers when unwinding interrupt frames") we changed our stack dumping logic to show the full registers whenever we find an interrupt frame on the stack. However we didn't notice that on 64-bit this doesn't show the final frame, ie. the interrupt that brought us in from userspace, whereas on 32-bit it does. That is due to confusion about the size of that last frame. The code in show_stack() calls validate_sp(), passing it STACK_INT_FRAME_SIZE to check the sp is at least that far below the top of the stack. However on 64-bit that size is too large for the final frame, because it includes the red zone, but we don't allocate a red zone for the first frame. So add a new define that encodes the correct size for 32-bit and 64-bit, and use it in show_stack(). This results in the full trace being shown on 64-bit, eg: sysrq: Trigger a crash Kernel panic - not syncing: sysrq triggered crash CPU: 0 PID: 83 Comm: sh Not tainted 5.11.0-rc2-gcc-8.2.0-00188-g571abcb96b10-dirty #649 Call Trace: [c00000000a1c3ac0] [c000000000897b70] dump_stack+0xc4/0x114 (unreliable) [c00000000a1c3b00] [c00000000014334c] panic+0x178/0x41c [c00000000a1c3ba0] [c00000000094e600] sysrq_handle_crash+0x40/0x50 [c00000000a1c3c00] [c00000000094ef98] __handle_sysrq+0xd8/0x210 [c00000000a1c3ca0] [c00000000094f820] write_sysrq_trigger+0x100/0x188 [c00000000a1c3ce0] [c0000000005559dc] proc_reg_write+0x10c/0x1b0 [c00000000a1c3d10] [c000000000479950] vfs_write+0xf0/0x360 [c00000000a1c3d60] [c000000000479d9c] ksys_write+0x7c/0x140 [c00000000a1c3db0] [c00000000002bf5c] system_call_exception+0x19c/0x2c0 [c00000000a1c3e10] [c00000000000d35c] system_call_common+0xec/0x278 --- interrupt: c00 at 0x7fff9fbab428 NIP: 00007fff9fbab428 LR: 000000001000b724 CTR: 0000000000000000 REGS: c00000000a1c3e80 TRAP: 0c00 Not tainted (5.11.0-rc2-gcc-8.2.0-00188-g571abcb96b10-dirty) MSR: 900000000280f033 <SF,HV,VEC,VSX,EE,PR,FP,ME,IR,DR,RI,LE> CR: 22002884 XER: 00000000 IRQMASK: 0 GPR00: 0000000000000004 00007fffc3cb8960 00007fff9fc59900 0000000000000001 GPR04: 000000002a4b32d0 0000000000000002 0000000000000063 0000000000000063 GPR08: 000000002a4b32d0 0000000000000000 0000000000000000 0000000000000000 GPR12: 0000000000000000 00007fff9fcca9a0 0000000000000000 0000000000000000 GPR16: 0000000000000000 0000000000000000 0000000000000000 00000000100b8fd0 GPR20: 000000002a4b3485 00000000100b8f90 0000000000000000 0000000000000000 GPR24: 000000002a4b0440 00000000100e77b8 0000000000000020 000000002a4b32d0 GPR28: 0000000000000001 0000000000000002 000000002a4b32d0 0000000000000001 NIP [00007fff9fbab428] 0x7fff9fbab428 LR [000000001000b724] 0x1000b724 --- interrupt: c00 Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20210209141627.2898485-1-mpe@ellerman.id.au Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-03-17powerpc/pci: Add ppc_md.discover_phbs()Oliver O'Halloran1-0/+3
[ Upstream commit 5537fcb319d016ce387f818dd774179bc03217f5 ] On many powerpc platforms the discovery and initalisation of pci_controllers (PHBs) happens inside of setup_arch(). This is very early in boot (pre-initcalls) and means that we're initialising the PHB long before many basic kernel services (slab allocator, debugfs, a real ioremap) are available. On PowerNV this causes an additional problem since we map the PHB registers with ioremap(). As of commit d538aadc2718 ("powerpc/ioremap: warn on early use of ioremap()") a warning is printed because we're using the "incorrect" API to setup and MMIO mapping in searly boot. The kernel does provide early_ioremap(), but that is not intended to create long-lived MMIO mappings and a seperate warning is printed by generic code if early_ioremap() mappings are "leaked." This is all fixable with dumb hacks like using early_ioremap() to setup the initial mapping then replacing it with a real ioremap later on in boot, but it does raise the question: Why the hell are we setting up the PHB's this early in boot? The old and wise claim it's due to "hysterical rasins." Aside from amused grapes there doesn't appear to be any real reason to maintain the current behaviour. Already most of the newer embedded platforms perform PHB discovery in an arch_initcall and between the end of setup_arch() and the start of initcalls none of the generic kernel code does anything PCI related. On powerpc scanning PHBs occurs in a subsys_initcall so it should be possible to move the PHB discovery to a core, postcore or arch initcall. This patch adds the ppc_md.discover_phbs hook and a core_initcall stub that calls it. The core_initcalls are the earliest to be called so this will any possibly issues with dependency between initcalls. This isn't just an academic issue either since on pseries and PowerNV EEH init occurs in an arch_initcall and depends on the pci_controllers being available, similarly the creation of pci_dns occurs at core_initcall_sync (i.e. between core and postcore initcalls). These problems need to be addressed seperately. Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Oliver O'Halloran <oohall@gmail.com> [mpe: Make discover_phbs() static] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20201103043523.916109-1-oohall@gmail.com Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-01-06powerpc/bitops: Fix possible undefined behaviour with fls() and fls64()Christophe Leroy1-2/+21
[ Upstream commit 1891ef21d92c4801ea082ee8ed478e304ddc6749 ] fls() and fls64() are using __builtin_ctz() and _builtin_ctzll(). On powerpc, those builtins trivially use ctlzw and ctlzd power instructions. Allthough those instructions provide the expected result with input argument 0, __builtin_ctz() and __builtin_ctzll() are documented as undefined for value 0. The easiest fix would be to use fls() and fls64() functions defined in include/asm-generic/bitops/builtin-fls.h and include/asm-generic/bitops/fls64.h, but GCC output is not optimal: 00000388 <testfls>: 388: 2c 03 00 00 cmpwi r3,0 38c: 41 82 00 10 beq 39c <testfls+0x14> 390: 7c 63 00 34 cntlzw r3,r3 394: 20 63 00 20 subfic r3,r3,32 398: 4e 80 00 20 blr 39c: 38 60 00 00 li r3,0 3a0: 4e 80 00 20 blr 000003b0 <testfls64>: 3b0: 2c 03 00 00 cmpwi r3,0 3b4: 40 82 00 1c bne 3d0 <testfls64+0x20> 3b8: 2f 84 00 00 cmpwi cr7,r4,0 3bc: 38 60 00 00 li r3,0 3c0: 4d 9e 00 20 beqlr cr7 3c4: 7c 83 00 34 cntlzw r3,r4 3c8: 20 63 00 20 subfic r3,r3,32 3cc: 4e 80 00 20 blr 3d0: 7c 63 00 34 cntlzw r3,r3 3d4: 20 63 00 40 subfic r3,r3,64 3d8: 4e 80 00 20 blr When the input of fls(x) is a constant, just check x for nullity and return either 0 or __builtin_clz(x). Otherwise, use cntlzw instruction directly. For fls64() on PPC64, do the same but with __builtin_clzll() and cntlzd instruction. On PPC32, lets take the generic fls64() which will use our fls(). The result is as expected: 00000388 <testfls>: 388: 7c 63 00 34 cntlzw r3,r3 38c: 20 63 00 20 subfic r3,r3,32 390: 4e 80 00 20 blr 000003a0 <testfls64>: 3a0: 2c 03 00 00 cmpwi r3,0 3a4: 40 82 00 10 bne 3b4 <testfls64+0x14> 3a8: 7c 83 00 34 cntlzw r3,r4 3ac: 20 63 00 20 subfic r3,r3,32 3b0: 4e 80 00 20 blr 3b4: 7c 63 00 34 cntlzw r3,r3 3b8: 20 63 00 40 subfic r3,r3,64 3bc: 4e 80 00 20 blr Fixes: 2fcff790dcb4 ("powerpc: Use builtin functions for fls()/__fls()/fls64()") Cc: stable@vger.kernel.org Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Acked-by: Segher Boessenkool <segher@kernel.crashing.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/348c2d3f19ffcff8abe50d52513f989c4581d000.1603375524.git.christophe.leroy@csgroup.eu Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-12-30powerpc/8xx: Fix early debug when SMC1 is relocatedChristophe Leroy1-0/+1
commit 1e78f723d6a52966bfe3804209dbf404fdc9d3bb upstream. When SMC1 is relocated and early debug is selected, the board hangs is ppc_md.setup_arch(). This is because ones the microcode has been loaded and SMC1 relocated, early debug writes in the weed. To allow smooth continuation, the SMC1 parameter RAM set up by the bootloader have to be copied into the new location. Fixes: 43db76f41824 ("powerpc/8xx: Add microcode patch to move SMC parameter RAM.") 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/b2f71f39eca543f1e4ec06596f09a8b12235c701.1607076683.git.christophe.leroy@csgroup.eu Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-12-30powerpc/feature: Add CPU_FTR_NOEXECUTE to G2_LEChristophe Leroy1-1/+1
commit 197493af414ee22427be3343637ac290a791925a upstream. G2_LE has a 603 core, add CPU_FTR_NOEXECUTE. Fixes: 385e89d5b20f ("powerpc/mm: add exec protection on powerpc 603") 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/39a530ee41d83f49747ab3af8e39c056450b9b4d.1602489653.git.christophe.leroy@csgroup.eu Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-12-30powerpc: Fix incorrect stw{, ux, u, x} instructions in __set_pte_atMathieu Desnoyers2-4/+4
commit d85be8a49e733dcd23674aa6202870d54bf5600d upstream. The placeholder for instruction selection should use the second argument's operand, which is %1, not %0. This could generate incorrect assembly code if the memory addressing of operand %0 is a different form from that of operand %1. Also remove the %Un placeholder because having %Un placeholders for two operands which are based on the same local var (ptep) doesn't make much sense. By the way, it doesn't change the current behaviour because "<>" constraint is missing for the associated "=m". [chleroy: revised commit log iaw segher's comments and removed %U0] Fixes: 9bf2b5cdc5fe ("powerpc: Fixes for CONFIG_PTE_64BIT for SMP support") Cc: <stable@vger.kernel.org> # v2.6.28+ Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Acked-by: Segher Boessenkool <segher@kernel.crashing.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/96354bd77977a6a933fe9020da57629007fdb920.1603358942.git.christophe.leroy@csgroup.eu Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-12-30powerpc/feature: Fix CPU_FTRS_ALWAYS by removing CPU_FTRS_GENERIC_32Christophe Leroy1-5/+0
[ Upstream commit 78665179e569c7e1fe102fb6c21d0f5b6951f084 ] On 8xx, we get the following features: [ 0.000000] cpu_features = 0x0000000000000100 [ 0.000000] possible = 0x0000000000000120 [ 0.000000] always = 0x0000000000000000 This is not correct. As CONFIG_PPC_8xx is mutually exclusive with all other configurations, the three lines should be equal. The problem is due to CPU_FTRS_GENERIC_32 which is taken when CONFIG_BOOK3S_32 is NOT selected. This CPU_FTRS_GENERIC_32 is pointless because there is no generic configuration supporting all 32 bits but book3s/32. Remove this pointless generic features definition to unbreak the calculation of 'possible' features and 'always' features. Fixes: 76bc080ef5a3 ("[POWERPC] Make default cputable entries reflect selected CPU family") Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/76a85f30bf981d1aeaae00df99321235494da254.1604426550.git.christophe.leroy@csgroup.eu Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-12-02powerpc/64s: Fix allnoconfig build since uaccess flushStephen Rothwell1-0/+2
[ Upstream commit b6b79dd53082db11070b4368d85dd6699ff0b063 ] Using DECLARE_STATIC_KEY_FALSE needs linux/jump_table.h. Otherwise the build fails with eg: arch/powerpc/include/asm/book3s/64/kup-radix.h:66:1: warning: data definition has no type or storage class 66 | DECLARE_STATIC_KEY_FALSE(uaccess_flush_key); Fixes: 9a32a7e78bd0 ("powerpc/64s: flush L1D after user accesses") Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> [mpe: Massage change log] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20201123184016.693fe464@canb.auug.org.au Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-12-02arch: pgtable: define MAX_POSSIBLE_PHYSMEM_BITS where neededArnd Bergmann2-0/+4
[ Upstream commit cef397038167ac15d085914493d6c86385773709 ] Stefan Agner reported a bug when using zsram on 32-bit Arm machines with RAM above the 4GB address boundary: Unable to handle kernel NULL pointer dereference at virtual address 00000000 pgd = a27bd01c [00000000] *pgd=236a0003, *pmd=1ffa64003 Internal error: Oops: 207 [#1] SMP ARM Modules linked in: mdio_bcm_unimac(+) brcmfmac cfg80211 brcmutil raspberrypi_hwmon hci_uart crc32_arm_ce bcm2711_thermal phy_generic genet CPU: 0 PID: 123 Comm: mkfs.ext4 Not tainted 5.9.6 #1 Hardware name: BCM2711 PC is at zs_map_object+0x94/0x338 LR is at zram_bvec_rw.constprop.0+0x330/0xa64 pc : [<c0602b38>] lr : [<c0bda6a0>] psr: 60000013 sp : e376bbe0 ip : 00000000 fp : c1e2921c r10: 00000002 r9 : c1dda730 r8 : 00000000 r7 : e8ff7a00 r6 : 00000000 r5 : 02f9ffa0 r4 : e3710000 r3 : 000fdffe r2 : c1e0ce80 r1 : ebf979a0 r0 : 00000000 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user Control: 30c5383d Table: 235c2a80 DAC: fffffffd Process mkfs.ext4 (pid: 123, stack limit = 0x495a22e6) Stack: (0xe376bbe0 to 0xe376c000) As it turns out, zsram needs to know the maximum memory size, which is defined in MAX_PHYSMEM_BITS when CONFIG_SPARSEMEM is set, or in MAX_POSSIBLE_PHYSMEM_BITS on the x86 architecture. The same problem will be hit on all 32-bit architectures that have a physical address space larger than 4GB and happen to not enable sparsemem and include asm/sparsemem.h from asm/pgtable.h. After the initial discussion, I suggested just always defining MAX_POSSIBLE_PHYSMEM_BITS whenever CONFIG_PHYS_ADDR_T_64BIT is set, or provoking a build error otherwise. This addresses all configurations that can currently have this runtime bug, but leaves all other configurations unchanged. I looked up the possible number of bits in source code and datasheets, here is what I found: - on ARC, CONFIG_ARC_HAS_PAE40 controls whether 32 or 40 bits are used - on ARM, CONFIG_LPAE enables 40 bit addressing, without it we never support more than 32 bits, even though supersections in theory allow up to 40 bits as well. - on MIPS, some MIPS32r1 or later chips support 36 bits, and MIPS32r5 XPA supports up to 60 bits in theory, but 40 bits are more than anyone will ever ship - On PowerPC, there are three different implementations of 36 bit addressing, but 32-bit is used without CONFIG_PTE_64BIT - On RISC-V, the normal page table format can support 34 bit addressing. There is no highmem support on RISC-V, so anything above 2GB is unused, but it might be useful to eventually support CONFIG_ZRAM for high pages. Fixes: 61989a80fb3a ("staging: zsmalloc: zsmalloc memory allocation library") Fixes: 02390b87a945 ("mm/zsmalloc: Prepare to variable MAX_PHYSMEM_BITS") Acked-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Reviewed-by: Stefan Agner <stefan@agner.ch> Tested-by: Stefan Agner <stefan@agner.ch> Acked-by: Mike Rapoport <rppt@linux.ibm.com> Link: https://lore.kernel.org/linux-mm/bdfa44bf1c570b05d6c70898e2bbb0acf234ecdf.1604762181.git.stefan@agner.ch/ Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-11-22powerpc: Only include kup-radix.h for 64-bit Book3SMichael Ellerman2-5/+14
commit 178d52c6e89c38d0553b0ac8b99927b11eb995b0 upstream. In kup.h we currently include kup-radix.h for all 64-bit builds, which includes Book3S and Book3E. The latter doesn't make sense, Book3E never uses the Radix MMU. This has worked up until now, but almost by accident, and the recent uaccess flush changes introduced a build breakage on Book3E because of the bad structure of the code. So disentangle things so that we only use kup-radix.h for Book3S. This requires some more stubs in kup.h. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Daniel Axtens <dja@axtens.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-11-22powerpc/64s: flush L1D after user accessesNicholas Piggin6-13/+44
commit 9a32a7e78bd0cd9a9b6332cbdc345ee5ffd0c5de upstream. IBM Power9 processors can speculatively operate on data in the L1 cache before it has been completely validated, via a way-prediction mechanism. It is not possible for an attacker to determine the contents of impermissible memory using this method, since these systems implement a combination of hardware and software security measures to prevent scenarios where protected data could be leaked. However these measures don't address the scenario where an attacker induces the operating system to speculatively execute instructions using data that the attacker controls. This can be used for example to speculatively bypass "kernel user access prevention" techniques, as discovered by Anthony Steinhauser of Google's Safeside Project. This is not an attack by itself, but there is a possibility it could be used in conjunction with side-channels or other weaknesses in the privileged code to construct an attack. This issue can be mitigated by flushing the L1 cache between privilege boundaries of concern. This patch flushes the L1 cache after user accesses. This is part of the fix for CVE-2020-4788. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Daniel Axtens <dja@axtens.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-11-22powerpc/64s: flush L1D on kernel entryNicholas Piggin4-1/+25
commit f79643787e0a0762d2409b7b8334e83f22d85695 upstream. [backporting note: we need to mark some exception handlers as out-of-line because the flushing makes them take too much space -- dja] IBM Power9 processors can speculatively operate on data in the L1 cache before it has been completely validated, via a way-prediction mechanism. It is not possible for an attacker to determine the contents of impermissible memory using this method, since these systems implement a combination of hardware and software security measures to prevent scenarios where protected data could be leaked. However these measures don't address the scenario where an attacker induces the operating system to speculatively execute instructions using data that the attacker controls. This can be used for example to speculatively bypass "kernel user access prevention" techniques, as discovered by Anthony Steinhauser of Google's Safeside Project. This is not an attack by itself, but there is a possibility it could be used in conjunction with side-channels or other weaknesses in the privileged code to construct an attack. This issue can be mitigated by flushing the L1 cache between privilege boundaries of concern. This patch flushes the L1 cache on kernel entry. This is part of the fix for CVE-2020-4788. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Daniel Axtens <dja@axtens.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-11-05powerpc/drmem: Make lmb_size 64 bitAneesh Kumar K.V1-2/+2
commit ec72024e35dddb88a81e40071c87ceb18b5ee835 upstream. Similar to commit 89c140bbaeee ("pseries: Fix 64 bit logical memory block panic") make sure different variables tracking lmb_size are updated to be 64 bit. This was found by code audit. Cc: stable@vger.kernel.org Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Acked-by: Nathan Lynch <nathanl@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20201007114836.282468-2-aneesh.kumar@linux.ibm.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-11-05powerpc: select ARCH_WANT_IRQS_OFF_ACTIVATE_MMNicholas Piggin1-1/+1
[ Upstream commit 66acd46080bd9e5ad2be4b0eb1d498d5145d058e ] powerpc uses IPIs in some situations to switch a kernel thread away from a lazy tlb mm, which is subject to the TLB flushing race described in the changelog introducing ARCH_WANT_IRQS_OFF_ACTIVATE_MM. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200914045219.3736466-3-npiggin@gmail.com Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-10-29powerpc/64s/radix: Fix mm_cpumask trimming race vs kthread_use_mmNicholas Piggin1-13/+0
[ Upstream commit a665eec0a22e11cdde708c1c256a465ebe768047 ] Commit 0cef77c7798a7 ("powerpc/64s/radix: flush remote CPUs out of single-threaded mm_cpumask") added a mechanism to trim the mm_cpumask of a process under certain conditions. One of the assumptions is that mm_users would not be incremented via a reference outside the process context with mmget_not_zero() then go on to kthread_use_mm() via that reference. That invariant was broken by io_uring code (see previous sparc64 fix), but I'll point Fixes: to the original powerpc commit because we are changing that assumption going forward, so this will make backports match up. Fix this by no longer relying on that assumption, but by having each CPU check the mm is not being used, and clearing their own bit from the mask only if it hasn't been switched-to by the time the IPI is processed. This relies on commit 38cf307c1f20 ("mm: fix kthread_use_mm() vs TLB invalidate") and ARCH_WANT_IRQS_OFF_ACTIVATE_MM to disable irqs over mm switch sequences. Fixes: 0cef77c7798a7 ("powerpc/64s/radix: flush remote CPUs out of single-threaded mm_cpumask") Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Reviewed-by: Michael Ellerman <mpe@ellerman.id.au> Depends-on: 38cf307c1f20 ("mm: fix kthread_use_mm() vs TLB invalidate") Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200914045219.3736466-5-npiggin@gmail.com Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-10-29powerpc/tau: Use appropriate temperature sample intervalFinn Thain1-1/+1
[ Upstream commit 66943005cc41f48e4d05614e8f76c0ca1812f0fd ] According to the MPC750 Users Manual, the SITV value in Thermal Management Register 3 is 13 bits long. The present code calculates the SITV value as 60 * 500 cycles. This would overflow to give 10 us on a 500 MHz CPU rather than the intended 60 us. (But according to the Microprocessor Datasheet, there is also a factor of 266 that has to be applied to this value on certain parts i.e. speed sort above 266 MHz.) Always use the maximum cycle count, as recommended by the Datasheet. Fixes: 1da177e4c3f41 ("Linux-2.6.12-rc2") Signed-off-by: Finn Thain <fthain@telegraphics.com.au> Tested-by: Stan Johnson <userm57@yahoo.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/896f542e5f0f1d6cf8218524c2b67d79f3d69b3c.1599260540.git.fthain@telegraphics.com.au Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-10-29powerpc/book3s64/hash/4k: Support large linear mapping range with 4KAneesh Kumar K.V1-7/+6
[ Upstream commit 7746406baa3bc9e23fdd7b7da2f04d86e25ab837 ] With commit: 0034d395f89d ("powerpc/mm/hash64: Map all the kernel regions in the same 0xc range"), we now split the 64TB address range into 4 contexts each of 16TB. That implies we can do only 16TB linear mapping. On some systems, eg. Power9, memory attached to nodes > 0 will appear above 16TB in the linear mapping. This resulted in kernel crash when we boot such systems in hash translation mode with 4K PAGE_SIZE. This patch updates the kernel mapping such that we now start supporting upto 61TB of memory with 4K. The kernel mapping now looks like below 4K PAGE_SIZE and hash translation. vmalloc start = 0xc0003d0000000000 IO start = 0xc0003e0000000000 vmemmap start = 0xc0003f0000000000 Our MAX_PHYSMEM_BITS for 4K is still 64TB even though we can only map 61TB. We prevent bolt mapping anything outside 61TB range by checking against H_VMALLOC_START. Fixes: 0034d395f89d ("powerpc/mm/hash64: Map all the kernel regions in the same 0xc range") Reported-by: Cameron Berkenpas <cam@neo-zeon.de> 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/20200608070904.387440-3-aneesh.kumar@linux.ibm.com Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-10-29pseries/drmem: don't cache node id in drmem_lmb structScott Cheloha1-21/+0
[ Upstream commit e5e179aa3a39c818db8fbc2dce8d2cd24adaf657 ] At memory hot-remove time we can retrieve an LMB's nid from its corresponding memory_block. There is no need to store the nid in multiple locations. Note that lmb_to_memblock() uses find_memory_block() to get the corresponding memory_block. As find_memory_block() runs in sub-linear time this approach is negligibly slower than what we do at present. In exchange for this lookup at hot-remove time we no longer need to call memory_add_physaddr_to_nid() during drmem_init() for each LMB. On powerpc, memory_add_physaddr_to_nid() is a linear search, so this spares us an O(n^2) initialization during boot. On systems with many LMBs that initialization overhead is palpable and disruptive. For example, on a box with 249854 LMBs we're seeing drmem_init() take upwards of 30 seconds to complete: [ 53.721639] drmem: initializing drmem v2 [ 80.604346] watchdog: BUG: soft lockup - CPU#65 stuck for 23s! [swapper/0:1] [ 80.604377] Modules linked in: [ 80.604389] CPU: 65 PID: 1 Comm: swapper/0 Not tainted 5.6.0-rc2+ #4 [ 80.604397] NIP: c0000000000a4980 LR: c0000000000a4940 CTR: 0000000000000000 [ 80.604407] REGS: c0002dbff8493830 TRAP: 0901 Not tainted (5.6.0-rc2+) [ 80.604412] MSR: 8000000002009033 <SF,VEC,EE,ME,IR,DR,RI,LE> CR: 44000248 XER: 0000000d [ 80.604431] CFAR: c0000000000a4a38 IRQMASK: 0 [ 80.604431] GPR00: c0000000000a4940 c0002dbff8493ac0 c000000001904400 c0003cfffffede30 [ 80.604431] GPR04: 0000000000000000 c000000000f4095a 000000000000002f 0000000010000000 [ 80.604431] GPR08: c0000bf7ecdb7fb8 c0000bf7ecc2d3c8 0000000000000008 c00c0002fdfb2001 [ 80.604431] GPR12: 0000000000000000 c00000001e8ec200 [ 80.604477] NIP [c0000000000a4980] hot_add_scn_to_nid+0xa0/0x3e0 [ 80.604486] LR [c0000000000a4940] hot_add_scn_to_nid+0x60/0x3e0 [ 80.604492] Call Trace: [ 80.604498] [c0002dbff8493ac0] [c0000000000a4940] hot_add_scn_to_nid+0x60/0x3e0 (unreliable) [ 80.604509] [c0002dbff8493b20] [c000000000087c10] memory_add_physaddr_to_nid+0x20/0x60 [ 80.604521] [c0002dbff8493b40] [c0000000010d4880] drmem_init+0x25c/0x2f0 [ 80.604530] [c0002dbff8493c10] [c000000000010154] do_one_initcall+0x64/0x2c0 [ 80.604540] [c0002dbff8493ce0] [c0000000010c4aa0] kernel_init_freeable+0x2d8/0x3a0 [ 80.604550] [c0002dbff8493db0] [c000000000010824] kernel_init+0x2c/0x148 [ 80.604560] [c0002dbff8493e20] [c00000000000b648] ret_from_kernel_thread+0x5c/0x74 [ 80.604567] Instruction dump: [ 80.604574] 392918e8 e9490000 e90a000a e92a0000 80ea000c 1d080018 3908ffe8 7d094214 [ 80.604586] 7fa94040 419d00dc e9490010 714a0088 <2faa0008> 409e00ac e9490000 7fbe5040 [ 89.047390] drmem: 249854 LMB(s) With a patched kernel on the same machine we're no longer seeing the soft lockup. drmem_init() now completes in negligible time, even when the LMB count is large. Fixes: b2d3b5ee66f2 ("powerpc/pseries: Track LMB nid instead of using device tree") Signed-off-by: Scott Cheloha <cheloha@linux.ibm.com> Reviewed-by: Nathan Lynch <nathanl@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200811015115.63677-1-cheloha@linux.ibm.com Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-10-29powerpc/pseries: explicitly reschedule during drmem_lmb list traversalNathan Lynch1-1/+17
[ Upstream commit 9d6792ffe140240ae54c881cc4183f9acc24b4df ] The drmem lmb list can have hundreds of thousands of entries, and unfortunately lookups take the form of linear searches. As long as this is the case, traversals have the potential to monopolize the CPU and provoke lockup reports, workqueue stalls, and the like unless they explicitly yield. Rather than placing cond_resched() calls within various for_each_drmem_lmb() loop blocks in the code, put it in the iteration expression of the loop macro itself so users can't omit it. Introduce a drmem_lmb_next() iteration helper function which calls cond_resched() at a regular interval during array traversal. Each iteration of the loop in DLPAR code paths can involve around ten RTAS calls which can each take up to 250us, so this ensures the check is performed at worst every few milliseconds. Fixes: 6c6ea53725b3 ("powerpc/mm: Separate ibm, dynamic-memory data from DT format") Signed-off-by: Nathan Lynch <nathanl@linux.ibm.com> Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200813151131.2070161-1-nathanl@linux.ibm.com Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-10-01KVM: PPC: Book3S HV: Treat TM-related invalid form instructions on P9 like ↵Gustavo Romero1-0/+3
the valid ones [ Upstream commit 1dff3064c764b5a51c367b949b341d2e38972bec ] On P9 DD2.2 due to a CPU defect some TM instructions need to be emulated by KVM. This is handled at first by the hardware raising a softpatch interrupt when certain TM instructions that need KVM assistance are executed in the guest. Althought some TM instructions per Power ISA are invalid forms they can raise a softpatch interrupt too. For instance, 'tresume.' instruction as defined in the ISA must have bit 31 set (1), but an instruction that matches 'tresume.' PO and XO opcode fields but has bit 31 not set (0), like 0x7cfe9ddc, also raises a softpatch interrupt. Similarly for 'treclaim.' and 'trechkpt.' instructions with bit 31 = 0, i.e. 0x7c00075c and 0x7c0007dc, respectively. Hence, if a code like the following is executed in the guest it will raise a softpatch interrupt just like a 'tresume.' when the TM facility is enabled ('tabort. 0' in the example is used only to enable the TM facility): int main() { asm("tabort. 0; .long 0x7cfe9ddc;"); } Currently in such a case KVM throws a complete trace like: [345523.705984] WARNING: CPU: 24 PID: 64413 at arch/powerpc/kvm/book3s_hv_tm.c:211 kvmhv_p9_tm_emulation+0x68/0x620 [kvm_hv] [345523.705985] Modules linked in: kvm_hv(E) xt_conntrack ipt_REJECT nf_reject_ipv4 xt_tcpudp ip6table_mangle ip6table_nat iptable_mangle iptable_nat nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 ebtable_filter ebtables ip6table_filter ip6_tables iptable_filter bridge stp llc sch_fq_codel ipmi_powernv at24 vmx_crypto ipmi_devintf ipmi_msghandler ibmpowernv uio_pdrv_genirq kvm opal_prd uio leds_powernv ib_iser rdma_cm iw_cm ib_cm ib_core iscsi_tcp libiscsi_tcp libiscsi scsi_transport_iscsi ip_tables x_tables autofs4 btrfs blake2b_generic zstd_compress raid10 raid456 async_raid6_recov async_memcpy async_pq async_xor async_tx libcrc32c xor raid6_pq raid1 raid0 multipath linear tg3 crct10dif_vpmsum crc32c_vpmsum ipr [last unloaded: kvm_hv] [345523.706030] CPU: 24 PID: 64413 Comm: CPU 0/KVM Tainted: G W E 5.5.0+ #1 [345523.706031] NIP: c0080000072cb9c0 LR: c0080000072b5e80 CTR: c0080000085c7850 [345523.706034] REGS: c000000399467680 TRAP: 0700 Tainted: G W E (5.5.0+) [345523.706034] MSR: 900000010282b033 <SF,HV,VEC,VSX,EE,FP,ME,IR,DR,RI,LE,TM[E]> CR: 24022428 XER: 00000000 [345523.706042] CFAR: c0080000072b5e7c IRQMASK: 0 GPR00: c0080000072b5e80 c000000399467910 c0080000072db500 c000000375ccc720 GPR04: c000000375ccc720 00000003fbec0000 0000a10395dda5a6 0000000000000000 GPR08: 000000007cfe9ddc 7cfe9ddc000005dc 7cfe9ddc7c0005dc c0080000072cd530 GPR12: c0080000085c7850 c0000003fffeb800 0000000000000001 00007dfb737f0000 GPR16: c0002001edcca558 0000000000000000 0000000000000000 0000000000000001 GPR20: c000000001b21258 c0002001edcca558 0000000000000018 0000000000000000 GPR24: 0000000001000000 ffffffffffffffff 0000000000000001 0000000000001500 GPR28: c0002001edcc4278 c00000037dd80000 800000050280f033 c000000375ccc720 [345523.706062] NIP [c0080000072cb9c0] kvmhv_p9_tm_emulation+0x68/0x620 [kvm_hv] [345523.706065] LR [c0080000072b5e80] kvmppc_handle_exit_hv.isra.53+0x3e8/0x798 [kvm_hv] [345523.706066] Call Trace: [345523.706069] [c000000399467910] [c000000399467940] 0xc000000399467940 (unreliable) [345523.706071] [c000000399467950] [c000000399467980] 0xc000000399467980 [345523.706075] [c0000003994679f0] [c0080000072bd1c4] kvmhv_run_single_vcpu+0xa1c/0xb80 [kvm_hv] [345523.706079] [c000000399467ac0] [c0080000072bd8e0] kvmppc_vcpu_run_hv+0x5b8/0xb00 [kvm_hv] [345523.706087] [c000000399467b90] [c0080000085c93cc] kvmppc_vcpu_run+0x34/0x48 [kvm] [345523.706095] [c000000399467bb0] [c0080000085c582c] kvm_arch_vcpu_ioctl_run+0x244/0x420 [kvm] [345523.706101] [c000000399467c40] [c0080000085b7498] kvm_vcpu_ioctl+0x3d0/0x7b0 [kvm] [345523.706105] [c000000399467db0] [c0000000004adf9c] ksys_ioctl+0x13c/0x170 [345523.706107] [c000000399467e00] [c0000000004adff8] sys_ioctl+0x28/0x80 [345523.706111] [c000000399467e20] [c00000000000b278] system_call+0x5c/0x68 [345523.706112] Instruction dump: [345523.706114] 419e0390 7f8a4840 409d0048 6d497c00 2f89075d 419e021c 6d497c00 2f8907dd [345523.706119] 419e01c0 6d497c00 2f8905dd 419e00a4 <0fe00000> 38210040 38600000 ebc1fff0 and then treats the executed instruction as a 'nop'. However the POWER9 User's Manual, in section "4.6.10 Book II Invalid Forms", informs that for TM instructions bit 31 is in fact ignored, thus for the TM-related invalid forms ignoring bit 31 and handling them like the valid forms is an acceptable way to handle them. POWER8 behaves the same way too. This commit changes the handling of the cases here described by treating the TM-related invalid forms that can generate a softpatch interrupt just like their valid forms (w/ bit 31 = 1) instead of as a 'nop' and by gently reporting any other unrecognized case to the host and treating it as illegal instruction instead of throwing a trace and treating it as a 'nop'. Signed-off-by: Gustavo Romero <gromero@linux.ibm.com> Reviewed-by: Segher Boessenkool <segher@kernel.crashing.org> Acked-By: Michael Neuling <mikey@neuling.org> Reviewed-by: Leonardo Bras <leonardo@linux.ibm.com> Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-09-23powerpc/book3s64/radix: Fix boot failure with large amount of guest memoryAneesh Kumar K.V1-5/+5
[ Upstream commit 103a8542cb35b5130f732d00b0419a594ba1b517 ] If the hypervisor doesn't support hugepages, the kernel ends up allocating a large number of page table pages. The early page table allocation was wrongly setting the max memblock limit to ppc64_rma_size with radix translation which resulted in boot failure as shown below. Kernel panic - not syncing: early_alloc_pgtable: Failed to allocate 16777216 bytes align=0x1000000 nid=-1 from=0x0000000000000000 max_addr=0xffffffffffffffff CPU: 0 PID: 0 Comm: swapper Not tainted 5.8.0-24.9-default+ #2 Call Trace: [c0000000016f3d00] [c0000000007c6470] dump_stack+0xc4/0x114 (unreliable) [c0000000016f3d40] [c00000000014c78c] panic+0x164/0x418 [c0000000016f3dd0] [c000000000098890] early_alloc_pgtable+0xe0/0xec [c0000000016f3e60] [c0000000010a5440] radix__early_init_mmu+0x360/0x4b4 [c0000000016f3ef0] [c000000001099bac] early_init_mmu+0x1c/0x3c [c0000000016f3f10] [c00000000109a320] early_setup+0x134/0x170 This was because the kernel was checking for the radix feature before we enable the feature via mmu_features. This resulted in the kernel using hash restrictions on radix. Rework the early init code such that the kernel boot with memblock restrictions as imposed by hash. At that point, the kernel still hasn't finalized the translation the kernel will end up using. We have three different ways of detecting radix. 1. dt_cpu_ftrs_scan -> used only in case of PowerNV 2. ibm,pa-features -> Used when we don't use cpu_dt_ftr_scan 3. CAS -> Where we negotiate with hypervisor about the supported translation. We look at 1 or 2 early in the boot and after that, we look at the CAS vector to finalize the translation the kernel will use. We also support a kernel command line option (disable_radix) to switch to hash. Update the memblock limit after mmu_early_init_devtree() if the kernel is going to use radix translation. This forces some of the memblock allocations we do before mmu_early_init_devtree() to be within the RMA limit. Fixes: 2bfd65e45e87 ("powerpc/mm/radix: Add radix callbacks for early init routines") Reported-by: Shirisha Ganta <shiganta@in.ibm.com> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Reviewed-by: Hari Bathini <hbathini@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200828100852.426575-1-aneesh.kumar@linux.ibm.com Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-08-26KVM: Pass MMU notifier range flags to kvm_unmap_hva_range()Will Deacon1-1/+2
commit fdfe7cbd58806522e799e2a50a15aee7f2cbb7b6 upstream. The 'flags' field of 'struct mmu_notifier_range' is used to indicate whether invalidate_range_{start,end}() are permitted to block. In the case of kvm_mmu_notifier_invalidate_range_start(), this field is not forwarded on to the architecture-specific implementation of kvm_unmap_hva_range() and therefore the backend cannot sensibly decide whether or not to block. Add an extra 'flags' parameter to kvm_unmap_hva_range() so that architectures are aware as to whether or not they are permitted to block. Cc: <stable@vger.kernel.org> Cc: Marc Zyngier <maz@kernel.org> Cc: Suzuki K Poulose <suzuki.poulose@arm.com> Cc: James Morse <james.morse@arm.com> Signed-off-by: Will Deacon <will@kernel.org> Message-Id: <20200811102725.7121-2-will@kernel.org> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Will Deacon <will@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-08-21powerpc: Fix circular dependency between percpu.h and mmu.hMichael Ellerman1-2/+2
commit 0c83b277ada72b585e6a3e52b067669df15bcedb upstream. Recently random.h started including percpu.h (see commit f227e3ec3b5c ("random32: update the net random state on interrupt and activity")), which broke corenet64_smp_defconfig: In file included from /linux/arch/powerpc/include/asm/paca.h:18, from /linux/arch/powerpc/include/asm/percpu.h:13, from /linux/include/linux/random.h:14, from /linux/lib/uuid.c:14: /linux/arch/powerpc/include/asm/mmu.h:139:22: error: unknown type name 'next_tlbcam_idx' 139 | DECLARE_PER_CPU(int, next_tlbcam_idx); This is due to a circular header dependency: asm/mmu.h includes asm/percpu.h, which includes asm/paca.h, which includes asm/mmu.h Which means DECLARE_PER_CPU() isn't defined when mmu.h needs it. We can fix it by moving the include of paca.h below the include of asm-generic/percpu.h. This moves the include of paca.h out of the #ifdef __powerpc64__, but that is OK because paca.h is almost entirely inside #ifdef CONFIG_PPC64 anyway. It also moves the include of paca.h out of the #ifdef CONFIG_SMP, which could possibly break something, but seems to have no ill effects. Fixes: f227e3ec3b5c ("random32: update the net random state on interrupt and activity") Cc: stable@vger.kernel.org # v5.8 Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200804130558.292328-1-mpe@ellerman.id.au Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-08-19powerpc/32s: Fix CONFIG_BOOK3S_601 usesMichael Ellerman2-2/+2
[ Upstream commit df4d4ef22446b3a789a4efd74d34f2ec1e24deb2 ] We have two uses of CONFIG_BOOK3S_601, which doesn't exist. Fix them to use CONFIG_PPC_BOOK3S_601 which is the correct symbol. Fixes: 12c3f1fd87bf ("powerpc/32s: get rid of CPU_FTR_601 feature") Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200724131728.1643966-5-mpe@ellerman.id.au Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-08-19powerpc/perf: Fix missing is_sier_aviable() during buildMadhavan Srinivasan1-0/+2
[ Upstream commit 3c9450c053f88e525b2db1e6990cdf34d14e7696 ] Compilation error: arch/powerpc/perf/perf_regs.c:80:undefined reference to `.is_sier_available' Currently is_sier_available() is part of core-book3s.c, which is added to build based on CONFIG_PPC_PERF_CTRS. A config with CONFIG_PERF_EVENTS and without CONFIG_PPC_PERF_CTRS will have a build break because of missing is_sier_available(). In practice it only breaks when CONFIG_FSL_EMB_PERF_EVENT=n because that also guards the usage of is_sier_available(). That only happens with CONFIG_PPC_BOOK3E_64=y and CONFIG_FSL_SOC_BOOKE=n. Patch adds is_sier_available() in asm/perf_event.h to fix the build break for configs missing CONFIG_PPC_PERF_CTRS. Fixes: 333804dc3b7a ("powerpc/perf: Update perf_regs structure to include SIER") Reported-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com> [mpe: Add detail about CONFIG_FSL_SOC_BOOKE] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200614083604.302611-1-maddy@linux.ibm.com Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-08-19powerpc/rtas: don't online CPUs for partition suspendNathan Lynch1-2/+0
[ Upstream commit ec2fc2a9e9bbad9023aab65bc472ce7a3ca8608f ] Partition suspension, used for hibernation and migration, requires that the OS place all but one of the LPAR's processor threads into one of two states prior to calling the ibm,suspend-me RTAS function: * the architected offline state (via RTAS stop-self); or * the H_JOIN hcall, which does not return until the partition resumes execution Using H_CEDE as the offline mode, introduced by commit 3aa565f53c39 ("powerpc/pseries: Add hooks to put the CPU into an appropriate offline state"), means that any threads which are offline from Linux's point of view must be moved to one of those two states before a partition suspension can proceed. This was eventually addressed in commit 120496ac2d2d ("powerpc: Bring all threads online prior to migration/hibernation"), which added code to temporarily bring up any offline processor threads so they can call H_JOIN. Conceptually this is fine, but the implementation has had multiple races with cpu hotplug operations initiated from user space[1][2][3], the error handling is fragile, and it generates user-visible cpu hotplug events which is a lot of noise for a platform feature that's supposed to minimize disruption to workloads. With commit 3aa565f53c39 ("powerpc/pseries: Add hooks to put the CPU into an appropriate offline state") reverted, this code becomes unnecessary, so remove it. Since any offline CPUs now are truly offline from the platform's point of view, it is no longer necessary to bring up CPUs only to have them call H_JOIN and then go offline again upon resuming. Only active threads are required to call H_JOIN; stopped threads can be left alone. [1] commit a6717c01ddc2 ("powerpc/rtas: use device model APIs and serialization during LPM") [2] commit 9fb603050ffd ("powerpc/rtas: retry when cpu offline races with suspend/migration") [3] commit dfd718a2ed1f ("powerpc/rtas: Fix a potential race between CPU-Offline & Migration") Fixes: 120496ac2d2d ("powerpc: Bring all threads online prior to migration/hibernation") Signed-off-by: Nathan Lynch <nathanl@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200612051238.1007764-3-nathanl@linux.ibm.com Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-08-11Revert "powerpc/kasan: Fix shadow pages allocation failure"Christophe Leroy1-0/+2
commit b506923ee44ae87fc9f4de16b53feb313623e146 upstream. 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 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-06-24powerpc/64s/pgtable: fix an undefined behaviourQian Cai1-4/+19
[ Upstream commit c2e929b18cea6cbf71364f22d742d9aad7f4677a ] Booting a power9 server with hash MMU could trigger an undefined behaviour because pud_offset(p4d, 0) will do, 0 >> (PAGE_SHIFT:16 + PTE_INDEX_SIZE:8 + H_PMD_INDEX_SIZE:10) Fix it by converting pud_index() and friends to static inline functions. UBSAN: shift-out-of-bounds in arch/powerpc/mm/ptdump/ptdump.c:282:15 shift exponent 34 is too large for 32-bit type 'int' CPU: 6 PID: 1 Comm: swapper/0 Not tainted 5.6.0-rc4-next-20200303+ #13 Call Trace: dump_stack+0xf4/0x164 (unreliable) ubsan_epilogue+0x18/0x78 __ubsan_handle_shift_out_of_bounds+0x160/0x21c walk_pagetables+0x2cc/0x700 walk_pud at arch/powerpc/mm/ptdump/ptdump.c:282 (inlined by) walk_pagetables at arch/powerpc/mm/ptdump/ptdump.c:311 ptdump_check_wx+0x8c/0xf0 mark_rodata_ro+0x48/0x80 kernel_init+0x74/0x194 ret_from_kernel_thread+0x5c/0x74 Suggested-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Qian Cai <cai@lca.pw> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Reviewed-by: Christophe Leroy <christophe.leroy@c-s.fr> Link: https://lore.kernel.org/r/20200306044852.3236-1-cai@lca.pw Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-06-24powerpc/64: Don't initialise init_task->thread.regsMichael Ellerman1-1/+0
[ Upstream commit 7ffa8b7dc11752827329e4e84a574ea6aaf24716 ] Aneesh increased the size of struct pt_regs by 16 bytes and started seeing this WARN_ON: smp: Bringing up secondary CPUs ... ------------[ cut here ]------------ WARNING: CPU: 0 PID: 0 at arch/powerpc/kernel/process.c:455 giveup_all+0xb4/0x110 Modules linked in: CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.7.0-rc2-gcc-8.2.0-1.g8f6a41f-default+ #318 NIP: c00000000001a2b4 LR: c00000000001a29c CTR: c0000000031d0000 REGS: c0000000026d3980 TRAP: 0700 Not tainted (5.7.0-rc2-gcc-8.2.0-1.g8f6a41f-default+) MSR: 800000000282b033 <SF,VEC,VSX,EE,FP,ME,IR,DR,RI,LE> CR: 48048224 XER: 00000000 CFAR: c000000000019cc8 IRQMASK: 1 GPR00: c00000000001a264 c0000000026d3c20 c0000000026d7200 800000000280b033 GPR04: 0000000000000001 0000000000000000 0000000000000077 30206d7372203164 GPR08: 0000000000002000 0000000002002000 800000000280b033 3230303030303030 GPR12: 0000000000008800 c0000000031d0000 0000000000800050 0000000002000066 GPR16: 000000000309a1a0 000000000309a4b0 000000000309a2d8 000000000309a890 GPR20: 00000000030d0098 c00000000264da40 00000000fd620000 c0000000ff798080 GPR24: c00000000264edf0 c0000001007469f0 00000000fd620000 c0000000020e5e90 GPR28: c00000000264edf0 c00000000264d200 000000001db60000 c00000000264d200 NIP [c00000000001a2b4] giveup_all+0xb4/0x110 LR [c00000000001a29c] giveup_all+0x9c/0x110 Call Trace: [c0000000026d3c20] [c00000000001a264] giveup_all+0x64/0x110 (unreliable) [c0000000026d3c90] [c00000000001ae34] __switch_to+0x104/0x480 [c0000000026d3cf0] [c000000000e0b8a0] __schedule+0x320/0x970 [c0000000026d3dd0] [c000000000e0c518] schedule_idle+0x38/0x70 [c0000000026d3df0] [c00000000019c7c8] do_idle+0x248/0x3f0 [c0000000026d3e70] [c00000000019cbb8] cpu_startup_entry+0x38/0x40 [c0000000026d3ea0] [c000000000011bb0] rest_init+0xe0/0xf8 [c0000000026d3ed0] [c000000002004820] start_kernel+0x990/0x9e0 [c0000000026d3f90] [c00000000000c49c] start_here_common+0x1c/0x400 Which was unexpected. The warning is checking the thread.regs->msr value of the task we are switching from: usermsr = tsk->thread.regs->msr; ... WARN_ON((usermsr & MSR_VSX) && !((usermsr & MSR_FP) && (usermsr & MSR_VEC))); ie. if MSR_VSX is set then both of MSR_FP and MSR_VEC are also set. Dumping tsk->thread.regs->msr we see that it's: 0x1db60000 Which is not a normal looking MSR, in fact the only valid bit is MSR_VSX, all the other bits are reserved in the current definition of the MSR. We can see from the oops that it was swapper/0 that we were switching from when we hit the warning, ie. init_task. So its thread.regs points to the base (high addresses) in init_stack. Dumping the content of init_task->thread.regs, with the members of pt_regs annotated (the 16 bytes larger version), we see: 0000000000000000 c000000002780080 gpr[0] gpr[1] 0000000000000000 c000000002666008 gpr[2] gpr[3] c0000000026d3ed0 0000000000000078 gpr[4] gpr[5] c000000000011b68 c000000002780080 gpr[6] gpr[7] 0000000000000000 0000000000000000 gpr[8] gpr[9] c0000000026d3f90 0000800000002200 gpr[10] gpr[11] c000000002004820 c0000000026d7200 gpr[12] gpr[13] 000000001db60000 c0000000010aabe8 gpr[14] gpr[15] c0000000010aabe8 c0000000010aabe8 gpr[16] gpr[17] c00000000294d598 0000000000000000 gpr[18] gpr[19] 0000000000000000 0000000000001ff8 gpr[20] gpr[21] 0000000000000000 c00000000206d608 gpr[22] gpr[23] c00000000278e0cc 0000000000000000 gpr[24] gpr[25] 000000002fff0000 c000000000000000 gpr[26] gpr[27] 0000000002000000 0000000000000028 gpr[28] gpr[29] 000000001db60000 0000000004750000 gpr[30] gpr[31] 0000000002000000 000000001db60000 nip msr 0000000000000000 0000000000000000 orig_r3 ctr c00000000000c49c 0000000000000000 link xer 0000000000000000 0000000000000000 ccr softe 0000000000000000 0000000000000000 trap dar 0000000000000000 0000000000000000 dsisr result 0000000000000000 0000000000000000 ppr kuap 0000000000000000 0000000000000000 pad[2] pad[3] This looks suspiciously like stack frames, not a pt_regs. If we look closely we can see return addresses from the stack trace above, c000000002004820 (start_kernel) and c00000000000c49c (start_here_common). init_task->thread.regs is setup at build time in processor.h: #define INIT_THREAD { \ .ksp = INIT_SP, \ .regs = (struct pt_regs *)INIT_SP - 1, /* XXX bogus, I think */ \ The early boot code where we setup the initial stack is: LOAD_REG_ADDR(r3,init_thread_union) /* set up a stack pointer */ LOAD_REG_IMMEDIATE(r1,THREAD_SIZE) add r1,r3,r1 li r0,0 stdu r0,-STACK_FRAME_OVERHEAD(r1) Which creates a stack frame of size 112 bytes (STACK_FRAME_OVERHEAD). Which is far too small to contain a pt_regs. So the result is init_task->thread.regs is pointing at some stack frames on the init stack, not at a pt_regs. We have gotten away with this for so long because with pt_regs at its current size the MSR happens to point into the first frame, at a location that is not written to by the early asm. With the 16 byte expansion the MSR falls into the second frame, which is used by the compiler, and collides with a saved register that tends to be non-zero. As far as I can see this has been wrong since the original merge of 64-bit ppc support, back in 2002. Conceptually swapper should have no regs, it never entered from userspace, and in fact that's what we do on 32-bit. It's also presumably what the "bogus" comment is referring to. So I think the right fix is to just not-initialise regs at all. I'm slightly worried this will break some code that isn't prepared for a NULL regs, but we'll have to see. Remove the comment in head_64.S which refers to us setting up the regs (even though we never did), and is otherwise not really accurate any more. Reported-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/20200428123130.73078-1-mpe@ellerman.id.au Signed-off-by: Sasha Levin <sashal@kernel.org>