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2023-12-20powerpc/ftrace: Fix stack teardown in ftrace_no_traceNaveen N Rao
[ Upstream commit 4b3338aaa74d7d4ec5b6734dc298f0db94ec83d2 ] Commit 41a506ef71eb ("powerpc/ftrace: Create a dummy stackframe to fix stack unwind") added use of a new stack frame on ftrace entry to fix stack unwind. However, the commit missed updating the offset used while tearing down the ftrace stack when ftrace is disabled. Fix the same. In addition, the commit missed saving the correct stack pointer in pt_regs. Update the same. Fixes: 41a506ef71eb ("powerpc/ftrace: Create a dummy stackframe to fix stack unwind") Cc: stable@vger.kernel.org # v6.5+ Signed-off-by: Naveen N Rao <naveen@kernel.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20231130065947.2188860-1-naveen@kernel.org Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-12-08powerpc: Don't clobber f0/vs0 during fp|altivec register saveTimothy Pearson
commit 5e1d824f9a283cbf90f25241b66d1f69adb3835b upstream. During floating point and vector save to thread data f0/vs0 are clobbered by the FPSCR/VSCR store routine. This has been obvserved to lead to userspace register corruption and application data corruption with io-uring. Fix it by restoring f0/vs0 after FPSCR/VSCR store has completed for all the FP, altivec, VMX register save paths. Tested under QEMU in kvm mode, running on a Talos II workstation with dual POWER9 DD2.2 CPUs. Additional detail (mpe): Typically save_fpu() is called from __giveup_fpu() which saves the FP regs and also *turns off FP* in the tasks MSR, meaning the kernel will reload the FP regs from the thread struct before letting the task use FP again. So in that case save_fpu() is free to clobber f0 because the FP regs no longer hold live values for the task. There is another case though, which is the path via: sys_clone() ... copy_process() dup_task_struct() arch_dup_task_struct() flush_all_to_thread() save_all() That path saves the FP regs but leaves them live. That's meant as an optimisation for a process that's using FP/VSX and then calls fork(), leaving the regs live means the parent process doesn't have to take a fault after the fork to get its FP regs back. The optimisation was added in commit 8792468da5e1 ("powerpc: Add the ability to save FPU without giving it up"). That path does clobber f0, but f0 is volatile across function calls, and typically programs reach copy_process() from userspace via a syscall wrapper function. So in normal usage f0 being clobbered across a syscall doesn't cause visible data corruption. But there is now a new path, because io-uring can call copy_process() via create_io_thread() from the signal handling path. That's OK if the signal is handled as part of syscall return, but it's not OK if the signal is handled due to some other interrupt. That path is: interrupt_return_srr_user() interrupt_exit_user_prepare() interrupt_exit_user_prepare_main() do_notify_resume() get_signal() task_work_run() create_worker_cb() create_io_worker() copy_process() dup_task_struct() arch_dup_task_struct() flush_all_to_thread() save_all() if (tsk->thread.regs->msr & MSR_FP) save_fpu() # f0 is clobbered and potentially live in userspace Note the above discussion applies equally to save_altivec(). Fixes: 8792468da5e1 ("powerpc: Add the ability to save FPU without giving it up") Cc: stable@vger.kernel.org # v4.6+ Closes: https://lore.kernel.org/all/480932026.45576726.1699374859845.JavaMail.zimbra@raptorengineeringinc.com/ Closes: https://lore.kernel.org/linuxppc-dev/480221078.47953493.1700206777956.JavaMail.zimbra@raptorengineeringinc.com/ Tested-by: Timothy Pearson <tpearson@raptorengineering.com> Tested-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Timothy Pearson <tpearson@raptorengineering.com> [mpe: Reword change log to describe exact path of corruption & other minor tweaks] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/1921539696.48534988.1700407082933.JavaMail.zimbra@raptorengineeringinc.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-12-08KVM: PPC: Book3S HV: Fix KVM_RUN clobbering FP/VEC user registersNicholas Piggin
commit dc158d23b33df9033bcc8e7117e8591dd2f9d125 upstream. Before running a guest, the host process (e.g., QEMU) FP/VEC registers are saved if they were being used, similarly to when the kernel uses FP registers. The guest values are then loaded into regs, and the host process registers will be restored lazily when it uses FP/VEC. KVM HV has a bug here: the host process registers do get saved, but the user MSR bits remain enabled, which indicates the registers are valid for the process. After they are clobbered by running the guest, this valid indication causes the host process to take on the FP/VEC register values of the guest. Fixes: 34e119c96b2b ("KVM: PPC: Book3S HV P9: Reduce mtmsrd instructions required to save host SPRs") Cc: stable@vger.kernel.org # v5.17+ Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20231122025811.2973-1-npiggin@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-11-28powerpc/powernv: Fix fortify source warnings in opal-prd.cMichael Ellerman
commit feea65a338e52297b68ceb688eaf0ffc50310a83 upstream. As reported by Mahesh & Aneesh, opal_prd_msg_notifier() triggers a FORTIFY_SOURCE warning: memcpy: detected field-spanning write (size 32) of single field "&item->msg" at arch/powerpc/platforms/powernv/opal-prd.c:355 (size 4) WARNING: CPU: 9 PID: 660 at arch/powerpc/platforms/powernv/opal-prd.c:355 opal_prd_msg_notifier+0x174/0x188 [opal_prd] NIP opal_prd_msg_notifier+0x174/0x188 [opal_prd] LR opal_prd_msg_notifier+0x170/0x188 [opal_prd] Call Trace: opal_prd_msg_notifier+0x170/0x188 [opal_prd] (unreliable) notifier_call_chain+0xc0/0x1b0 atomic_notifier_call_chain+0x2c/0x40 opal_message_notify+0xf4/0x2c0 This happens because the copy is targeting item->msg, which is only 4 bytes in size, even though the enclosing item was allocated with extra space following the msg. To fix the warning define struct opal_prd_msg with a union of the header and a flex array, and have the memcpy target the flex array. Reported-by: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com> Reported-by: Mahesh Salgaonkar <mahesh@linux.ibm.com> Tested-by: Mahesh Salgaonkar <mahesh@linux.ibm.com> Reviewed-by: Mahesh Salgaonkar <mahesh@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20230821142820.497107-1-mpe@ellerman.id.au Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-11-28powerpc/perf: Fix disabling BHRB and instruction samplingNicholas Piggin
commit ea142e590aec55ba40c5affb4d49e68c713c63dc upstream. When the PMU is disabled, MMCRA is not updated to disable BHRB and instruction sampling. This can lead to those features remaining enabled, which can slow down a real or emulated CPU. Fixes: 1cade527f6e9 ("powerpc/perf: BHRB control to disable BHRB logic when not used") Cc: stable@vger.kernel.org # v5.9+ Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20231018153423.298373-1-npiggin@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-11-20powerpc/pseries: fix potential memory leak in init_cpu_associativity()Wang Yufen
[ Upstream commit 95f1a128cd728a7257d78e868f1f5a145fc43736 ] If the vcpu_associativity alloc memory successfully but the pcpu_associativity fails to alloc memory, the vcpu_associativity memory leaks. Fixes: d62c8deeb6e6 ("powerpc/pseries: Provide vcpu dispatch statistics") Signed-off-by: Wang Yufen <wangyufen@huawei.com> Reviewed-by: "Naveen N. Rao" <naveen.n.rao@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/1671003983-10794-1-git-send-email-wangyufen@huawei.com Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-11-20powerpc/imc-pmu: Use the correct spinlock initializer.Sebastian Andrzej Siewior
[ Upstream commit 007240d59c11f87ac4f6cfc6a1d116630b6b634c ] The macro __SPIN_LOCK_INITIALIZER() is implementation specific. Users that desire to initialize a spinlock in a struct must use __SPIN_LOCK_UNLOCKED(). Use __SPIN_LOCK_UNLOCKED() for the spinlock_t in imc_global_refc. Fixes: 76d588dddc459 ("powerpc/imc-pmu: Fix use of mutex in IRQs disabled section") Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20230309134831.Nz12nqsU@linutronix.de Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-11-20powerpc/vas: Limit open window failure messages in log buffferHaren Myneni
[ Upstream commit 73b25505ce043b561028e5571d84dc82aa53c2b4 ] The VAS open window call prints error message and returns -EBUSY after the migration suspend event initiated and until the resume event completed on the destination system. It can cause the log buffer filled with these error messages if the user space issues continuous open window calls. Similar case even for DLPAR CPU remove event when no credits are available until the credits are freed or with the other DLPAR CPU add event. So changes in the patch to use pr_err_ratelimited() instead of pr_err() to display open window failure and not-available credits error messages. Use pr_fmt() and make the corresponding changes to have the consistencein prefix all pr_*() messages (vas-api.c). Fixes: 37e6764895ef ("powerpc/pseries/vas: Add VAS migration handler") Signed-off-by: Haren Myneni <haren@linux.ibm.com> [mpe: Use "vas-api" as the prefix to match the file name.] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20231019215033.1335251-1-haren@linux.ibm.com Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-11-20powerpc/xive: Fix endian conversion sizeBenjamin Gray
[ Upstream commit ff7a60ab1e065257a0e467c13b519f4debcd7fcf ] Sparse reports a size mismatch in the endian swap. The Opal implementation[1] passes the value as a __be64, and the receiving variable out_qsize is a u64, so the use of be32_to_cpu() appears to be an error. [1]: https://github.com/open-power/skiboot/blob/80e2b1dc73/hw/xive.c#L3854 Fixes: 88ec6b93c8e7 ("powerpc/xive: add OPAL extensions for the XIVE native exploitation support") Signed-off-by: Benjamin Gray <bgray@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20231011053711.93427-2-bgray@linux.ibm.com Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-11-20powerpc/40x: Remove stale PTE_ATOMIC_UPDATES macroChristophe Leroy
[ Upstream commit cc8ee288f484a2a59c01ccd4d8a417d6ed3466e3 ] 40x TLB handlers were reworked by commit 2c74e2586bb9 ("powerpc/40x: Rework 40x PTE access and TLB miss") to not require PTE_ATOMIC_UPDATES anymore. Then commit 4e1df545e2fa ("powerpc/pgtable: Drop PTE_ATOMIC_UPDATES") removed all code related to PTE_ATOMIC_UPDATES. Remove left over PTE_ATOMIC_UPDATES macro. Fixes: 2c74e2586bb9 ("powerpc/40x: Rework 40x PTE access and TLB miss") Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/f061db5857fcd748f84a6707aad01754686ce97e.1695659959.git.christophe.leroy@csgroup.eu Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-11-20powerpc: Only define __parse_fpscr() when requiredChristophe Leroy
[ Upstream commit c7e0d9bb9154c6e6b2ac8746faba27b53393f25e ] Clang 17 reports: arch/powerpc/kernel/traps.c:1167:19: error: unused function '__parse_fpscr' [-Werror,-Wunused-function] __parse_fpscr() is called from two sites. First call is guarded by #ifdef CONFIG_PPC_FPU_REGS Second call is guarded by CONFIG_MATH_EMULATION which selects CONFIG_PPC_FPU_REGS. So only define __parse_fpscr() when CONFIG_PPC_FPU_REGS is defined. Reported-by: kernel test robot <lkp@intel.com> Closes: https://lore.kernel.org/oe-kbuild-all/202309210327.WkqSd5Bq-lkp@intel.com/ Fixes: b6254ced4da6 ("powerpc/signal: Don't manage floating point regs when no FPU") Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/5de2998c57f3983563b27b39228ea9a7229d4110.1695385984.git.christophe.leroy@csgroup.eu Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-11-08powerpc/mm: Fix boot crash with FLATMEMMichael Ellerman
[ Upstream commit daa9ada2093ed23d52b4c1fe6e13cf78f55cc85f ] Erhard reported that his G5 was crashing with v6.6-rc kernels: mpic: Setting up HT PICs workarounds for U3/U4 BUG: Unable to handle kernel data access at 0xfeffbb62ffec65fe Faulting instruction address: 0xc00000000005dc40 Oops: Kernel access of bad area, sig: 11 [#1] BE PAGE_SIZE=4K MMU=Hash SMP NR_CPUS=2 PowerMac Modules linked in: CPU: 0 PID: 0 Comm: swapper/0 Tainted: G T 6.6.0-rc3-PMacGS #1 Hardware name: PowerMac11,2 PPC970MP 0x440101 PowerMac NIP: c00000000005dc40 LR: c000000000066660 CTR: c000000000007730 REGS: c0000000022bf510 TRAP: 0380 Tainted: G T (6.6.0-rc3-PMacGS) MSR: 9000000000001032 <SF,HV,ME,IR,DR,RI> CR: 44004242 XER: 00000000 IRQMASK: 3 GPR00: 0000000000000000 c0000000022bf7b0 c0000000010c0b00 00000000000001ac GPR04: 0000000003c80000 0000000000000300 c0000000f20001ae 0000000000000300 GPR08: 0000000000000006 feffbb62ffec65ff 0000000000000001 0000000000000000 GPR12: 9000000000001032 c000000002362000 c000000000f76b80 000000000349ecd8 GPR16: 0000000002367ba8 0000000002367f08 0000000000000006 0000000000000000 GPR20: 00000000000001ac c000000000f6f920 c0000000022cd985 000000000000000c GPR24: 0000000000000300 00000003b0a3691d c0003e008030000e 0000000000000000 GPR28: c00000000000000c c0000000f20001ee feffbb62ffec65fe 00000000000001ac NIP hash_page_do_lazy_icache+0x50/0x100 LR __hash_page_4K+0x420/0x590 Call Trace: hash_page_mm+0x364/0x6f0 do_hash_fault+0x114/0x2b0 data_access_common_virt+0x198/0x1f0 --- interrupt: 300 at mpic_init+0x4bc/0x10c4 NIP: c000000002020a5c LR: c000000002020a04 CTR: 0000000000000000 REGS: c0000000022bf9f0 TRAP: 0300 Tainted: G T (6.6.0-rc3-PMacGS) MSR: 9000000000001032 <SF,HV,ME,IR,DR,RI> CR: 24004248 XER: 00000000 DAR: c0003e008030000e DSISR: 40000000 IRQMASK: 1 ... NIP mpic_init+0x4bc/0x10c4 LR mpic_init+0x464/0x10c4 --- interrupt: 300 pmac_setup_one_mpic+0x258/0x2dc pmac_pic_init+0x28c/0x3d8 init_IRQ+0x90/0x140 start_kernel+0x57c/0x78c start_here_common+0x1c/0x20 A bisect pointed to the breakage beginning with commit 9fee28baa601 ("powerpc: implement the new page table range API"). Analysis of the oops pointed to a struct page with a corrupted compound_head being loaded via page_folio() -> _compound_head() in hash_page_do_lazy_icache(). The access by the mpic code is to an MMIO address, so the expectation is that the struct page for that address would be initialised by init_unavailable_range(), as pointed out by Aneesh. Instrumentation showed that was not the case, which eventually lead to the realisation that pfn_valid() was returning false for that address, causing the struct page to not be initialised. Because the system is using FLATMEM, the version of pfn_valid() in memory_model.h is used: static inline int pfn_valid(unsigned long pfn) { ... return pfn >= pfn_offset && (pfn - pfn_offset) < max_mapnr; } Which relies on max_mapnr being initialised. Early in boot max_mapnr is zero meaning no PFNs are valid. max_mapnr is initialised in mem_init() called via: start_kernel() mm_core_init() # init/main.c:928 mem_init() But that is too late for the usage in init_unavailable_range() called via: start_kernel() setup_arch() # init/main.c:893 paging_init() free_area_init() init_unavailable_range() Although max_mapnr is currently set in mem_init(), the value is actually already available much earlier, as soon as mem_topology_setup() has completed, which is also before paging_init() is called. So move the initialisation there, which causes paging_init() to correctly initialise the struct page and fixes the bug. This bug seems to have been lurking for years, but went unnoticed because the pre-folio code was inspecting the uninitialised page->flags but not dereferencing it. Thanks to Erhard and Aneesh for help debugging. Reported-by: Erhard Furtner <erhard_f@mailbox.org> Closes: https://lore.kernel.org/all/20230929132750.3cd98452@yea/ Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20231023112500.1550208-1-mpe@ellerman.id.au Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-11-08powerpc/85xx: Fix math emulation exceptionChristophe Leroy
[ Upstream commit 8e8a12ecbc86700b5e1a3596ce2b3c43dafad336 ] Booting mpc85xx_defconfig kernel on QEMU leads to: Bad trap at PC: fe9bab0, SR: 2d000, vector=800 awk[82]: unhandled trap (5) at 0 nip fe9bab0 lr fe9e01c code 5 in libc-2.27.so[fe5a000+17a000] awk[82]: code: 3aa00000 3a800010 4bffe03c 9421fff0 7ca62b78 38a00000 93c10008 83c10008 awk[82]: code: 38210010 4bffdec8 9421ffc0 7c0802a6 <fc00048e> d8010008 4815190d 93810030 Trace/breakpoint trap WARNING: no useful console This is because allthough CONFIG_MATH_EMULATION is selected, Exception 800 calls unknown_exception(). Call emulation_assist_interrupt() instead. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/066caa6d9480365da9b8ed83692d7101e10ac5f8.1695657339.git.christophe.leroy@csgroup.eu Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-10-19powerpc/64e: Fix wrong test in __ptep_test_and_clear_young()Christophe Leroy
[ Upstream commit 5ea0bbaa32e8f54e9a57cfee4a3b8769b80be0d2 ] Commit 45201c879469 ("powerpc/nohash: Remove hash related code from nohash headers.") replaced: if ((pte_val(*ptep) & (_PAGE_ACCESSED | _PAGE_HASHPTE)) == 0) return 0; By: if (pte_young(*ptep)) return 0; But it should be: if (!pte_young(*ptep)) return 0; Fix it. Fixes: 45201c879469 ("powerpc/nohash: Remove hash related code from nohash headers.") Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/8bb7f06494e21adada724ede47a4c3d97e879d40.1695659959.git.christophe.leroy@csgroup.eu Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-10-19powerpc/8xx: Fix pte_access_permitted() for PAGE_NONEChristophe Leroy
[ Upstream commit 5d9cea8a552ee122e21fbd5a3c5d4eb85f648e06 ] On 8xx, PAGE_NONE is handled by setting _PAGE_NA instead of clearing _PAGE_USER. But then pte_user() returns 1 also for PAGE_NONE. As _PAGE_NA prevent reads, add a specific version of pte_read() that returns 0 when _PAGE_NA is set instead of always returning 1. Fixes: 351750331fc1 ("powerpc/mm: Introduce _PAGE_NA") Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/57bcfbe578e43123f9ed73e040229b80f1ad56ec.1695659959.git.christophe.leroy@csgroup.eu Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-10-19powerpc/47x: Fix 47x syscall return crashMichael Ellerman
commit f0eee815babed70a749d2496a7678be5b45b4c14 upstream. Eddie reported that newer kernels were crashing during boot on his 476 FSP2 system: kernel tried to execute user page (b7ee2000) - exploit attempt? (uid: 0) BUG: Unable to handle kernel instruction fetch Faulting instruction address: 0xb7ee2000 Oops: Kernel access of bad area, sig: 11 [#1] BE PAGE_SIZE=4K FSP-2 Modules linked in: CPU: 0 PID: 61 Comm: mount Not tainted 6.1.55-d23900f.ppcnf-fsp2 #1 Hardware name: ibm,fsp2 476fpe 0x7ff520c0 FSP-2 NIP:  b7ee2000 LR: 8c008000 CTR: 00000000 REGS: bffebd83 TRAP: 0400   Not tainted (6.1.55-d23900f.ppcnf-fs p2) MSR:  00000030 <IR,DR>  CR: 00001000  XER: 20000000 GPR00: c00110ac bffebe63 bffebe7e bffebe88 8c008000 00001000 00000d12 b7ee2000 GPR08: 00000033 00000000 00000000 c139df10 48224824 1016c314 10160000 00000000 GPR16: 10160000 10160000 00000008 00000000 10160000 00000000 10160000 1017f5b0 GPR24: 1017fa50 1017f4f0 1017fa50 1017f740 1017f630 00000000 00000000 1017f4f0 NIP [b7ee2000] 0xb7ee2000 LR [8c008000] 0x8c008000 Call Trace: Instruction dump: XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX ---[ end trace 0000000000000000 ]--- The problem is in ret_from_syscall where the check for icache_44x_need_flush is done. When the flush is needed the code jumps out-of-line to do the flush, and then intends to jump back to continue the syscall return. However the branch back to label 1b doesn't return to the correct location, instead branching back just prior to the return to userspace, causing bogus register values to be used by the rfi. The breakage was introduced by commit 6f76a01173cc ("powerpc/syscall: implement system call entry/exit logic in C for PPC32") which inadvertently removed the "1" label and reused it elsewhere. Fix it by adding named local labels in the correct locations. Note that the return label needs to be outside the ifdef so that CONFIG_PPC_47x=n compiles. Fixes: 6f76a01173cc ("powerpc/syscall: implement system call entry/exit logic in C for PPC32") Cc: stable@vger.kernel.org # v5.12+ Reported-by: Eddie James <eajames@linux.ibm.com> Tested-by: Eddie James <eajames@linux.ibm.com> Link: https://lore.kernel.org/linuxppc-dev/fdaadc46-7476-9237-e104-1d2168526e72@linux.ibm.com/ Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu> Link: https://msgid.link/20231010114750.847794-1-mpe@ellerman.id.au Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-10-06powerpc/watchpoints: Annotate atomic context in more placesBenjamin Gray
[ Upstream commit 27646b2e02b096a6936b3e3b6ba334ae20763eab ] It can be easy to miss that the notifier mechanism invokes the callbacks in an atomic context, so add some comments to that effect on the two handlers we register here. Signed-off-by: Benjamin Gray <bgray@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20230829063457.54157-4-bgray@linux.ibm.com Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-10-06powerpc/watchpoint: Disable pagefaults when getting user instructionBenjamin Gray
[ Upstream commit 3241f260eb830d27d09cc604690ec24533fdb433 ] This is called in an atomic context, so is not allowed to sleep if a user page needs to be faulted in and has nowhere it can be deferred to. The pagefault_disabled() function is documented as preventing user access methods from sleeping. In practice the page will be mapped in nearly always because we are reading the instruction that just triggered the watchpoint trap. Signed-off-by: Benjamin Gray <bgray@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20230829063457.54157-3-bgray@linux.ibm.com Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-10-06powerpc/watchpoints: Disable preemption in thread_change_pc()Benjamin Gray
[ Upstream commit cc879ab3ce39bc39f9b1d238b283f43a5f6f957d ] thread_change_pc() uses CPU local data, so must be protected from swapping CPUs while it is reading the breakpoint struct. The error is more noticeable after 1e60f3564bad ("powerpc/watchpoints: Track perf single step directly on the breakpoint"), which added an unconditional __this_cpu_read() call in thread_change_pc(). However the existing __this_cpu_read() that runs if a breakpoint does need to be re-inserted has the same issue. Signed-off-by: Benjamin Gray <bgray@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20230829063457.54157-2-bgray@linux.ibm.com Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-10-06powerpc/perf/hv-24x7: Update domain value checkKajol Jain
[ Upstream commit 4ff3ba4db5943cac1045e3e4a3c0463ea10f6930 ] Valid domain value is in range 1 to HV_PERF_DOMAIN_MAX. Current code has check for domain value greater than or equal to HV_PERF_DOMAIN_MAX. But the check for domain value 0 is missing. Fix this issue by adding check for domain value 0. Before: # ./perf stat -v -e hv_24x7/CPM_ADJUNCT_INST,domain=0,core=1/ sleep 1 Using CPUID 00800200 Control descriptor is not initialized Error: The sys_perf_event_open() syscall returned with 5 (Input/output error) for event (hv_24x7/CPM_ADJUNCT_INST,domain=0,core=1/). /bin/dmesg | grep -i perf may provide additional information. Result from dmesg: [ 37.819387] hv-24x7: hcall failed: [0 0x60040000 0x100 0] => ret 0xfffffffffffffffc (-4) detail=0x2000000 failing ix=0 After: # ./perf stat -v -e hv_24x7/CPM_ADJUNCT_INST,domain=0,core=1/ sleep 1 Using CPUID 00800200 Control descriptor is not initialized Warning: hv_24x7/CPM_ADJUNCT_INST,domain=0,core=1/ event is not supported by the kernel. failed to read counter hv_24x7/CPM_ADJUNCT_INST,domain=0,core=1/ Fixes: ebd4a5a3ebd9 ("powerpc/perf/hv-24x7: Minor improvements") Reported-by: Krishan Gopal Sarawast <krishang@linux.vnet.ibm.com> Signed-off-by: Kajol Jain <kjain@linux.ibm.com> Tested-by: Disha Goel <disgoel@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20230825055601.360083-1-kjain@linux.ibm.com Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-09-23powerpc/pseries: fix possible memory leak in ibmebus_bus_init()ruanjinjie
[ Upstream commit afda85b963c12947e298ad85d757e333aa40fd74 ] If device_register() returns error in ibmebus_bus_init(), name of kobject which is allocated in dev_set_name() called in device_add() is leaked. As comment of device_add() says, it should call put_device() to drop the reference count that was set in device_initialize() when it fails, so the name can be freed in kobject_cleanup(). Signed-off-by: ruanjinjie <ruanjinjie@huawei.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20221110011929.3709774-1-ruanjinjie@huawei.com Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-09-13powerpc/iommu: Fix notifiers being shared by PCI and VIO busesRussell Currey
[ Upstream commit c37b6908f7b2bd24dcaaf14a180e28c9132b9c58 ] fail_iommu_setup() registers the fail_iommu_bus_notifier struct to both PCI and VIO buses. struct notifier_block is a linked list node, so this causes any notifiers later registered to either bus type to also be registered to the other since they share the same node. This causes issues in (at least) the vgaarb code, which registers a notifier for PCI buses. pci_notify() ends up being called on a vio device, converted with to_pci_dev() even though it's not a PCI device, and finally makes a bad access in vga_arbiter_add_pci_device() as discovered with KASAN: BUG: KASAN: slab-out-of-bounds in vga_arbiter_add_pci_device+0x60/0xe00 Read of size 4 at addr c000000264c26fdc by task swapper/0/1 Call Trace: dump_stack_lvl+0x1bc/0x2b8 (unreliable) print_report+0x3f4/0xc60 kasan_report+0x244/0x698 __asan_load4+0xe8/0x250 vga_arbiter_add_pci_device+0x60/0xe00 pci_notify+0x88/0x444 notifier_call_chain+0x104/0x320 blocking_notifier_call_chain+0xa0/0x140 device_add+0xac8/0x1d30 device_register+0x58/0x80 vio_register_device_node+0x9ac/0xce0 vio_bus_scan_register_devices+0xc4/0x13c __machine_initcall_pseries_vio_device_init+0x94/0xf0 do_one_initcall+0x12c/0xaa8 kernel_init_freeable+0xa48/0xba8 kernel_init+0x64/0x400 ret_from_kernel_thread+0x5c/0x64 Fix this by creating separate notifier_block structs for each bus type. Fixes: d6b9a81b2a45 ("powerpc: IOMMU fault injection") Reported-by: Nageswara R Sastry <rnsastry@linux.ibm.com> Signed-off-by: Russell Currey <ruscur@russell.cc> Tested-by: Nageswara R Sastry <rnsastry@linux.ibm.com> Reviewed-by: Andrew Donnellan <ajd@linux.ibm.com> [mpe: Add #ifdef to fix CONFIG_IBMVIO=n build] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20230322035322.328709-1-ruscur@russell.cc Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-09-13powerpc/mpc5xxx: Add missing fwnode_handle_put()Liang He
[ Upstream commit b9bbbf4979073d5536b7650decd37fcb901e6556 ] In mpc5xxx_fwnode_get_bus_frequency(), we should add fwnode_handle_put() when break out of the iteration fwnode_for_each_parent_node() as it will automatically increase and decrease the refcounter. Fixes: de06fba62af6 ("powerpc/mpc5xxx: Switch mpc5xxx_get_bus_frequency() to use fwnode") Signed-off-by: Liang He <windhl@126.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20230322030423.1855440-1-windhl@126.com Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-09-13powerpc/pseries: Fix hcall tracepoints with JUMP_LABEL=nNicholas Piggin
[ Upstream commit 750bd41aeaeb1f0e0128aa4f8fcd6dd759713641 ] With JUMP_LABEL=n, hcall_tracepoint_refcount's address is being tested instead of its value. This results in the tracing slowpath always being taken unnecessarily. Fixes: 9a10ccb29c0a2 ("powerpc/pseries: move hcall_tracepoint_refcount out of .toc") Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20230509091600.70994-1-npiggin@gmail.com Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-09-13powerpc/pseries: Rework lppaca_shared_proc() to avoid DEBUG_PREEMPTRussell Currey
[ Upstream commit eac030b22ea12cdfcbb2e941c21c03964403c63f ] lppaca_shared_proc() takes a pointer to the lppaca which is typically accessed through get_lppaca(). With DEBUG_PREEMPT enabled, this leads to checking if preemption is enabled, for example: BUG: using smp_processor_id() in preemptible [00000000] code: grep/10693 caller is lparcfg_data+0x408/0x19a0 CPU: 4 PID: 10693 Comm: grep Not tainted 6.5.0-rc3 #2 Call Trace: dump_stack_lvl+0x154/0x200 (unreliable) check_preemption_disabled+0x214/0x220 lparcfg_data+0x408/0x19a0 ... This isn't actually a problem however, as it does not matter which lppaca is accessed, the shared proc state will be the same. vcpudispatch_stats_procfs_init() already works around this by disabling preemption, but the lparcfg code does not, erroring any time /proc/powerpc/lparcfg is accessed with DEBUG_PREEMPT enabled. Instead of disabling preemption on the caller side, rework lppaca_shared_proc() to not take a pointer and instead directly access the lppaca, bypassing any potential preemption checks. Fixes: f13c13a00512 ("powerpc: Stop using non-architected shared_proc field in lppaca") Signed-off-by: Russell Currey <ruscur@russell.cc> [mpe: Rework to avoid needing a definition in paca.h and lppaca.h] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20230823055317.751786-4-mpe@ellerman.id.au Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-09-13powerpc: Don't include lppaca.h in paca.hMichael Ellerman
[ Upstream commit 1aa000667669fa855853decbb1c69e974d8ff716 ] By adding a forward declaration for struct lppaca we can untangle paca.h and lppaca.h. Also move get_lppaca() into lppaca.h for consistency. Add includes of lppaca.h to some files that need it. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20230823055317.751786-3-mpe@ellerman.id.au Stable-dep-of: eac030b22ea1 ("powerpc/pseries: Rework lppaca_shared_proc() to avoid DEBUG_PREEMPT") Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-09-13powerpc/perf: Convert fsl_emb notifier to state machine callbacksChristophe Leroy
[ Upstream commit 34daf445f82bd3a4df852bb5f1dffd792ac830a0 ] CC arch/powerpc/perf/core-fsl-emb.o arch/powerpc/perf/core-fsl-emb.c:675:6: error: no previous prototype for 'hw_perf_event_setup' [-Werror=missing-prototypes] 675 | void hw_perf_event_setup(int cpu) | ^~~~~~~~~~~~~~~~~~~ Looks like fsl_emb was completely missed by commit 3f6da3905398 ("perf: Rework and fix the arch CPU-hotplug hooks") So, apply same changes as commit 3f6da3905398 ("perf: Rework and fix the arch CPU-hotplug hooks") then commit 57ecde42cc74 ("powerpc/perf: Convert book3s notifier to state machine callbacks") While at it, also fix following error: arch/powerpc/perf/core-fsl-emb.c: In function 'perf_event_interrupt': arch/powerpc/perf/core-fsl-emb.c:648:13: error: variable 'found' set but not used [-Werror=unused-but-set-variable] 648 | int found = 0; | ^~~~~ Fixes: 3f6da3905398 ("perf: Rework and fix the arch CPU-hotplug hooks") Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/603e1facb32608f88f40b7d7b9094adc50e7b2dc.1692349125.git.christophe.leroy@csgroup.eu Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-09-13powerpc/fadump: reset dump area size if fadump memory reserve failsSourabh Jain
[ Upstream commit d1eb75e0dfed80d2d85b664e28a39f65b290ab55 ] In case fadump_reserve_mem() fails to reserve memory, the reserve_dump_area_size variable will retain the reserve area size. This will lead to /sys/kernel/fadump/mem_reserved node displaying an incorrect memory reserved by fadump. To fix this problem, reserve dump area size variable is set to 0 if fadump failed to reserve memory. Fixes: 8255da95e545 ("powerpc/fadump: release all the memory above boot memory size") Signed-off-by: Sourabh Jain <sourabhjain@linux.ibm.com> Acked-by: Mahesh Salgaonkar <mahesh@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20230704050715.203581-1-sourabhjain@linux.ibm.com Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-09-13powerpc/radix: Move some functions into #ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLEChristophe Leroy
[ Upstream commit 4a9dd8f292efd614f0a18452e6474fe19ae17b47 ] With skiboot_defconfig, Clang reports: CC arch/powerpc/mm/book3s64/radix_tlb.o arch/powerpc/mm/book3s64/radix_tlb.c:419:20: error: unused function '_tlbie_pid_lpid' [-Werror,-Wunused-function] static inline void _tlbie_pid_lpid(unsigned long pid, unsigned long lpid, ^ arch/powerpc/mm/book3s64/radix_tlb.c:663:20: error: unused function '_tlbie_va_range_lpid' [-Werror,-Wunused-function] static inline void _tlbie_va_range_lpid(unsigned long start, unsigned long end, ^ This is because those functions are only called from functions enclosed in a #ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE Move below functions inside that #ifdef * __tlbie_pid_lpid(unsigned long pid, * __tlbie_va_lpid(unsigned long va, unsigned long pid, * fixup_tlbie_pid_lpid(unsigned long pid, unsigned long lpid) * _tlbie_pid_lpid(unsigned long pid, unsigned long lpid, * fixup_tlbie_va_range_lpid(unsigned long va, * __tlbie_va_range_lpid(unsigned long start, unsigned long end, * _tlbie_va_range_lpid(unsigned long start, unsigned long end, Fixes: f0c6fbbb9050 ("KVM: PPC: Book3S HV: Add support for H_RPT_INVALIDATE") Reported-by: kernel test robot <lkp@intel.com> Closes: https://lore.kernel.org/oe-kbuild-all/202307260802.Mjr99P5O-lkp@intel.com/ Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/3d72efd39f986ee939d068af69fdce28bd600766.1691568093.git.christophe.leroy@csgroup.eu Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-09-13powerpc/powermac: Use early_* IO variants in via_calibrate_decr()Benjamin Gray
[ Upstream commit 86582e6189dd8f9f52c25d46c70fe5d111da6345 ] On a powermac platform, via the call path: start_kernel() time_init() ppc_md.calibrate_decr() (pmac_calibrate_decr) via_calibrate_decr() ioremap() and iounmap() are called. The unmap can enable interrupts unexpectedly (cond_resched() in vunmap_pmd_range()), which causes a warning later in the boot sequence in start_kernel(). Use the early_* variants of these IO functions to prevent this. The issue is pre-existing, but is surfaced by commit 721255b9826b ("genirq: Use a maple tree for interrupt descriptor management"). Signed-off-by: Benjamin Gray <bgray@linux.ibm.com> Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20230706010816.72682-1-bgray@linux.ibm.com Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-09-13powerpc/boot: Disable power10 features after BOOTAFLAGS assignmentNathan Chancellor
[ Upstream commit 2b694fc96fe33a7c042e3a142d27d945c8c668b0 ] When building the boot wrapper assembly files with clang after commit 648a1783fe25 ("powerpc/boot: Fix boot wrapper code generation with CONFIG_POWER10_CPU"), the following warnings appear for each file built: '-prefixed' is not a recognized feature for this target (ignoring feature) '-pcrel' is not a recognized feature for this target (ignoring feature) While it is questionable whether or not LLVM should be emitting a warning when passed negative versions of code generation flags when building assembly files (since it does not emit a warning for the altivec and vsx flags), it is easy enough to work around this by just moving the disabled flags to BOOTCFLAGS after the assignment of BOOTAFLAGS, so that they are not added when building assembly files. Do so to silence the warnings. Fixes: 648a1783fe25 ("powerpc/boot: Fix boot wrapper code generation with CONFIG_POWER10_CPU") Link: https://github.com/ClangBuiltLinux/linux/issues/1839 Reviewed-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Nathan Chancellor <nathan@kernel.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20230427-remove-power10-args-from-boot-aflags-clang-v1-1-9107f7c943bc@kernel.org Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-08-23powerpc/rtas_flash: allow user copy to flash block cache objectsNathan Lynch
commit 4f3175979e62de3b929bfa54a0db4b87d36257a7 upstream. With hardened usercopy enabled (CONFIG_HARDENED_USERCOPY=y), using the /proc/powerpc/rtas/firmware_update interface to prepare a system firmware update yields a BUG(): kernel BUG at mm/usercopy.c:102! Oops: Exception in kernel mode, sig: 5 [#1] LE PAGE_SIZE=64K MMU=Hash SMP NR_CPUS=2048 NUMA pSeries Modules linked in: CPU: 0 PID: 2232 Comm: dd Not tainted 6.5.0-rc3+ #2 Hardware name: IBM,8408-E8E POWER8E (raw) 0x4b0201 0xf000004 of:IBM,FW860.50 (SV860_146) hv:phyp pSeries NIP: c0000000005991d0 LR: c0000000005991cc CTR: 0000000000000000 REGS: c0000000148c76a0 TRAP: 0700 Not tainted (6.5.0-rc3+) MSR: 8000000000029033 <SF,EE,ME,IR,DR,RI,LE> CR: 24002242 XER: 0000000c CFAR: c0000000001fbd34 IRQMASK: 0 [ ... GPRs omitted ... ] NIP usercopy_abort+0xa0/0xb0 LR usercopy_abort+0x9c/0xb0 Call Trace: usercopy_abort+0x9c/0xb0 (unreliable) __check_heap_object+0x1b4/0x1d0 __check_object_size+0x2d0/0x380 rtas_flash_write+0xe4/0x250 proc_reg_write+0xfc/0x160 vfs_write+0xfc/0x4e0 ksys_write+0x90/0x160 system_call_exception+0x178/0x320 system_call_common+0x160/0x2c4 The blocks of the firmware image are copied directly from user memory to objects allocated from flash_block_cache, so flash_block_cache must be created using kmem_cache_create_usercopy() to mark it safe for user access. Fixes: 6d07d1cd300f ("usercopy: Restrict non-usercopy caches to size 0") Signed-off-by: Nathan Lynch <nathanl@linux.ibm.com> Reviewed-by: Kees Cook <keescook@chromium.org> [mpe: Trim and indent oops] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20230810-rtas-flash-vs-hardened-usercopy-v2-1-dcf63793a938@linux.ibm.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-08-23powerpc/kasan: Disable KCOV in KASAN codeBenjamin Gray
[ Upstream commit ccb381e1af1ace292153c88eb1fffa5683d16a20 ] As per the generic KASAN code in mm/kasan, disable KCOV with KCOV_INSTRUMENT := n in the makefile. This fixes a ppc64 boot hang when KCOV and KASAN are enabled. kasan_early_init() gets called before a PACA is initialised, but the KCOV hook expects a valid PACA. Suggested-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Benjamin Gray <bgray@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20230710044143.146840-1-bgray@linux.ibm.com Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-08-11powerpc/mm/altmap: Fix altmap boundary checkAneesh Kumar K.V
[ Upstream commit 6722b25712054c0f903b839b8f5088438dd04df3 ] altmap->free includes the entire free space from which altmap blocks can be allocated. So when checking whether the kernel is doing altmap block free, compute the boundary correctly, otherwise memory hotunplug can fail. Fixes: 9ef34630a461 ("powerpc/mm: Fallback to RAM if the altmap is unusable") Signed-off-by: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com> Reviewed-by: David Hildenbrand <david@redhat.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20230724181320.471386-1-aneesh.kumar@linux.ibm.com Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-08-11powerpc/ftrace: Create a dummy stackframe to fix stack unwindNaveen N Rao
commit 41a506ef71eb38d94fe133f565c87c3e06ccc072 upstream. With ppc64 -mprofile-kernel and ppc32 -pg, profiling instructions to call into ftrace are emitted right at function entry. The instruction sequence used is minimal to reduce overhead. Crucially, a stackframe is not created for the function being traced. This breaks stack unwinding since the function being traced does not have a stackframe for itself. As such, it never shows up in the backtrace: /sys/kernel/debug/tracing # echo 1 > /proc/sys/kernel/stack_tracer_enabled /sys/kernel/debug/tracing # cat stack_trace Depth Size Location (17 entries) ----- ---- -------- 0) 4144 32 ftrace_call+0x4/0x44 1) 4112 432 get_page_from_freelist+0x26c/0x1ad0 2) 3680 496 __alloc_pages+0x290/0x1280 3) 3184 336 __folio_alloc+0x34/0x90 4) 2848 176 vma_alloc_folio+0xd8/0x540 5) 2672 272 __handle_mm_fault+0x700/0x1cc0 6) 2400 208 handle_mm_fault+0xf0/0x3f0 7) 2192 80 ___do_page_fault+0x3e4/0xbe0 8) 2112 160 do_page_fault+0x30/0xc0 9) 1952 256 data_access_common_virt+0x210/0x220 10) 1696 400 0xc00000000f16b100 11) 1296 384 load_elf_binary+0x804/0x1b80 12) 912 208 bprm_execve+0x2d8/0x7e0 13) 704 64 do_execveat_common+0x1d0/0x2f0 14) 640 160 sys_execve+0x54/0x70 15) 480 64 system_call_exception+0x138/0x350 16) 416 416 system_call_common+0x160/0x2c4 Fix this by having ftrace create a dummy stackframe for the function being traced. With this, backtraces now capture the function being traced: /sys/kernel/debug/tracing # cat stack_trace Depth Size Location (17 entries) ----- ---- -------- 0) 3888 32 _raw_spin_trylock+0x8/0x70 1) 3856 576 get_page_from_freelist+0x26c/0x1ad0 2) 3280 64 __alloc_pages+0x290/0x1280 3) 3216 336 __folio_alloc+0x34/0x90 4) 2880 176 vma_alloc_folio+0xd8/0x540 5) 2704 416 __handle_mm_fault+0x700/0x1cc0 6) 2288 96 handle_mm_fault+0xf0/0x3f0 7) 2192 48 ___do_page_fault+0x3e4/0xbe0 8) 2144 192 do_page_fault+0x30/0xc0 9) 1952 608 data_access_common_virt+0x210/0x220 10) 1344 16 0xc0000000334bbb50 11) 1328 416 load_elf_binary+0x804/0x1b80 12) 912 64 bprm_execve+0x2d8/0x7e0 13) 848 176 do_execveat_common+0x1d0/0x2f0 14) 672 192 sys_execve+0x54/0x70 15) 480 64 system_call_exception+0x138/0x350 16) 416 416 system_call_common+0x160/0x2c4 This results in two additional stores in the ftrace entry code, but produces reliable backtraces. Fixes: 153086644fd1 ("powerpc/ftrace: Add support for -mprofile-kernel ftrace ABI") Cc: stable@vger.kernel.org Signed-off-by: Naveen N Rao <naveen@kernel.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20230621051349.759567-1-naveen@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-08-11word-at-a-time: use the same return type for has_zero regardless of endiannessndesaulniers@google.com
[ Upstream commit 79e8328e5acbe691bbde029a52c89d70dcbc22f3 ] Compiling big-endian targets with Clang produces the diagnostic: fs/namei.c:2173:13: warning: use of bitwise '|' with boolean operands [-Wbitwise-instead-of-logical] } while (!(has_zero(a, &adata, &constants) | has_zero(b, &bdata, &constants))); ~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ || fs/namei.c:2173:13: note: cast one or both operands to int to silence this warning It appears that when has_zero was introduced, two definitions were produced with different signatures (in particular different return types). Looking at the usage in hash_name() in fs/namei.c, I suspect that has_zero() is meant to be invoked twice per while loop iteration; using logical-or would not update `bdata` when `a` did not have zeros. So I think it's preferred to always return an unsigned long rather than a bool than update the while loop in hash_name() to use a logical-or rather than bitwise-or. [ Also changed powerpc version to do the same - Linus ] Link: https://github.com/ClangBuiltLinux/linux/issues/1832 Link: https://lore.kernel.org/lkml/20230801-bitwise-v1-1-799bec468dc4@google.com/ Fixes: 36126f8f2ed8 ("word-at-a-time: make the interfaces truly generic") Debugged-by: Nathan Chancellor <nathan@kernel.org> Signed-off-by: Nick Desaulniers <ndesaulniers@google.com> Acked-by: Heiko Carstens <hca@linux.ibm.com> Cc: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-08-08init: Remove check_bugs() leftoversThomas Gleixner
commit 61235b24b9cb37c13fcad5b9596d59a1afdcec30 upstream Everything is converted over to arch_cpu_finalize_init(). Remove the check_bugs() leftovers including the empty stubs in asm-generic, alpha, parisc, powerpc and xtensa. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Link: https://lore.kernel.org/r/20230613224545.553215951@linutronix.de Signed-off-by: Daniel Sneddon <daniel.sneddon@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-08-03powerpc/pseries/vas: Hold mmap_mutex after mmap lock during window closeHaren Myneni
[ Upstream commit b59c9dc4d9d47b3c4572d826603fde507055b656 ] Commit 8ef7b9e1765a ("powerpc/pseries/vas: Close windows with DLPAR core removal") unmaps the window paste address and issues HCALL to close window in the hypervisor for migration or DLPAR core removal events. So holds mmap_mutex and then mmap lock before unmap the paste address. But if the user space issue mmap paste address at the same time with the migration event, coproc_mmap() is called after holding the mmap lock which can trigger deadlock when trying to acquire mmap_mutex in coproc_mmap(). t1: mmap() call to mmap t2: Migration event window paste address do_mmap2() migration_store() ksys_mmap_pgoff() pseries_migrate_partition() vm_mmap_pgoff() vas_migration_handler() Acquire mmap lock reconfig_close_windows() do_mmap() lock mmap_mutex mmap_region() Acquire mmap lock call_mmap() //Wait for mmap lock coproc_mmap() unmap vma lock mmap_mutex update window status //wait for mmap_mutex Release mmap lock mmap vma unlock mmap_mutex update window status unlock mmap_mutex ... Release mmap lock Fix this deadlock issue by holding mmap lock first before mmap_mutex in reconfig_close_windows(). Fixes: 8ef7b9e1765a ("powerpc/pseries/vas: Close windows with DLPAR core removal") Signed-off-by: Haren Myneni <haren@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20230716100506.7833-1-haren@linux.ibm.com Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-07-23powerpc/64s: Fix native_hpte_remove() to be irq-safeMichael Ellerman
commit 8bbe9fee5848371d4af101be445303cac8d880c5 upstream. Lockdep warns that the use of the hpte_lock in native_hpte_remove() is not safe against an IRQ coming in: ================================ WARNING: inconsistent lock state 6.4.0-rc2-g0c54f4d30ecc #1 Not tainted -------------------------------- inconsistent {IN-SOFTIRQ-W} -> {SOFTIRQ-ON-W} usage. qemu-system-ppc/93865 [HC0[0]:SC0[0]:HE1:SE1] takes: c0000000021f5180 (hpte_lock){+.?.}-{0:0}, at: native_lock_hpte+0x8/0xd0 {IN-SOFTIRQ-W} state was registered at: lock_acquire+0x134/0x3f0 native_lock_hpte+0x44/0xd0 native_hpte_insert+0xd4/0x2a0 __hash_page_64K+0x218/0x4f0 hash_page_mm+0x464/0x840 do_hash_fault+0x11c/0x260 data_access_common_virt+0x210/0x220 __ip_select_ident+0x140/0x150 ... net_rx_action+0x3bc/0x440 __do_softirq+0x180/0x534 ... sys_sendmmsg+0x34/0x50 system_call_exception+0x128/0x320 system_call_common+0x160/0x2e4 ... Possible unsafe locking scenario: CPU0 ---- lock(hpte_lock); <Interrupt> lock(hpte_lock); *** DEADLOCK *** ... Call Trace: dump_stack_lvl+0x98/0xe0 (unreliable) print_usage_bug.part.0+0x250/0x278 mark_lock+0xc9c/0xd30 __lock_acquire+0x440/0x1ca0 lock_acquire+0x134/0x3f0 native_lock_hpte+0x44/0xd0 native_hpte_remove+0xb0/0x190 kvmppc_mmu_map_page+0x650/0x698 [kvm_pr] kvmppc_handle_pagefault+0x534/0x6e8 [kvm_pr] kvmppc_handle_exit_pr+0x6d8/0xe90 [kvm_pr] after_sprg3_load+0x80/0x90 [kvm_pr] kvmppc_vcpu_run_pr+0x108/0x270 [kvm_pr] kvmppc_vcpu_run+0x34/0x48 [kvm] kvm_arch_vcpu_ioctl_run+0x340/0x470 [kvm] kvm_vcpu_ioctl+0x338/0x8b8 [kvm] sys_ioctl+0x7c4/0x13e0 system_call_exception+0x128/0x320 system_call_common+0x160/0x2e4 I suspect kvm_pr is the only caller that doesn't already have IRQs disabled, which is why this hasn't been reported previously. Fix it by disabling IRQs in native_hpte_remove(). Fixes: 35159b5717fa ("powerpc/64s: make HPTE lock and native_tlbie_lock irq-safe") Cc: stable@vger.kernel.org # v6.1+ Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20230517123033.18430-1-mpe@ellerman.id.au Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-07-23powerpc/security: Fix Speculation_Store_Bypass reporting on Power10Michael Ellerman
commit 5bcedc5931e7bd6928a2d8207078d4cb476b3b55 upstream. Nageswara reported that /proc/self/status was showing "vulnerable" for the Speculation_Store_Bypass feature on Power10, eg: $ grep Speculation_Store_Bypass: /proc/self/status Speculation_Store_Bypass: vulnerable But at the same time the sysfs files, and lscpu, were showing "Not affected". This turns out to simply be a bug in the reporting of the Speculation_Store_Bypass, aka. PR_SPEC_STORE_BYPASS, case. When SEC_FTR_STF_BARRIER was added, so that firmware could communicate the vulnerability was not present, the code in ssb_prctl_get() was not updated to check the new flag. So add the check for SEC_FTR_STF_BARRIER being disabled. Rather than adding the new check to the existing if block and expanding the comment to cover both cases, rewrite the three cases to be separate so they can be commented separately for clarity. Fixes: 84ed26fd00c5 ("powerpc/security: Add a security feature for STF barrier") Cc: stable@vger.kernel.org # v5.14+ Reported-by: Nageswara R Sastry <rnsastry@linux.ibm.com> Tested-by: Nageswara R Sastry <rnsastry@linux.ibm.com> Reviewed-by: Russell Currey <ruscur@russell.cc> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20230517074945.53188-1-mpe@ellerman.id.au Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-07-23powerpc: Fail build if using recordmcount with binutils v2.37Naveen N Rao
commit 25ea739ea1d4d3de41acc4f4eb2d1a97eee0eb75 upstream. binutils v2.37 drops unused section symbols, which prevents recordmcount from capturing mcount locations in sections that have no non-weak symbols. This results in a build failure with a message such as: Cannot find symbol for section 12: .text.perf_callchain_kernel. kernel/events/callchain.o: failed The change to binutils was reverted for v2.38, so this behavior is specific to binutils v2.37: https://sourceware.org/git/?p=binutils-gdb.git;a=commit;h=c09c8b42021180eee9495bd50d8b35e683d3901b Objtool is able to cope with such sections, so this issue is specific to recordmcount. Fail the build and print a warning if binutils v2.37 is detected and if we are using recordmcount. Cc: stable@vger.kernel.org Suggested-by: Joel Stanley <joel@jms.id.au> Signed-off-by: Naveen N Rao <naveen@kernel.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20230530061436.56925-1-naveen@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-07-19powerpc: dts: turris1x.dts: Fix PCIe MEM size for pci2 nodePali Rohár
[ Upstream commit abaa02fc944f2f9f2c2e1925ddaceaf35c48528c ] Freescale PCIe controllers on their PCIe Root Ports do not have any mappable PCI BAR allocate from PCIe MEM. Information about 1MB window on BAR0 of PCIe Root Port was misleading because Freescale PCIe controllers have at BAR0 position different register PEXCSRBAR, and kernel correctly skipts BAR0 for these Freescale PCIe Root Ports. So update comment about P2020 PCIe Root Port and decrease PCIe MEM size required for PCIe controller (pci2 node) on which is on-board xHCI controller. lspci confirms that on P2020 PCIe Root Port is no PCI BAR and /proc/iomem sees that only c0000000-c000ffff and c0010000-c0011fff ranges are used. Fixes: 54c15ec3b738 ("powerpc: dts: Add DTS file for CZ.NIC Turris 1.x routers") Signed-off-by: Pali Rohár <pali@kernel.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20230505172818.18416-1-pali@kernel.org Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-07-19powerpc: allow PPC_EARLY_DEBUG_CPM only when SERIAL_CPM=yRandy Dunlap
[ Upstream commit 39f49684036d24af800ff194c33c7b2653c591d7 ] In a randconfig with CONFIG_SERIAL_CPM=m and CONFIG_PPC_EARLY_DEBUG_CPM=y, there is a build error: ERROR: modpost: "udbg_putc" [drivers/tty/serial/cpm_uart/cpm_uart.ko] undefined! Prevent the build error by allowing PPC_EARLY_DEBUG_CPM only when SERIAL_CPM=y. Fixes: c374e00e17f1 ("[POWERPC] Add early debug console for CPM serial ports.") Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Reviewed-by: Pali Rohár <pali@kernel.org> Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20230701054714.30512-1-rdunlap@infradead.org Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-07-19powerpc/mm/dax: Fix the condition when checking if altmap vmemap can ↵Aneesh Kumar K.V
cross-boundary [ Upstream commit c8eebc4a99f15280654f23e914e746c40a516e50 ] Without this fix, the last subsection vmemmap can end up in memory even if the namespace is created with -M mem and has sufficient space in the altmap area. Fixes: cf387d9644d8 ("libnvdimm/altmap: Track namespace boundaries in altmap") Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Tested-by: Sachin Sant <sachinp@linux.ibm.com <mailto:sachinp@linux.ibm.com>> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20230616110826.344417-6-aneesh.kumar@linux.ibm.com Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-07-19powerpc/book3s64/mm: Fix DirectMap stats in /proc/meminfoAneesh Kumar K.V
[ Upstream commit 0da90af431abc3f497a38ec9ef6e43b0d0dabe80 ] On memory unplug reduce DirectMap page count correctly. root@ubuntu-guest:# grep Direct /proc/meminfo DirectMap4k: 0 kB DirectMap64k: 0 kB DirectMap2M: 115343360 kB DirectMap1G: 0 kB Before fix: root@ubuntu-guest:# ndctl disable-namespace all disabled 1 namespace root@ubuntu-guest:# grep Direct /proc/meminfo DirectMap4k: 0 kB DirectMap64k: 0 kB DirectMap2M: 115343360 kB DirectMap1G: 0 kB After fix: root@ubuntu-guest:# ndctl disable-namespace all disabled 1 namespace root@ubuntu-guest:# grep Direct /proc/meminfo DirectMap4k: 0 kB DirectMap64k: 0 kB DirectMap2M: 104857600 kB DirectMap1G: 0 kB Fixes: a2dc009afa9a ("powerpc/mm/book3s/radix: Add mapping statistics") Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Tested-by: Sachin Sant <sachinp@linux.ibm.com <mailto:sachinp@linux.ibm.com>> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20230616110826.344417-4-aneesh.kumar@linux.ibm.com Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-07-19powerpc: update ppc_save_regs to save current r1 in pt_regsAditya Gupta
[ Upstream commit b684c09f09e7a6af3794d4233ef785819e72db79 ] ppc_save_regs() skips one stack frame while saving the CPU register states. Instead of saving current R1, it pulls the previous stack frame pointer. When vmcores caused by direct panic call (such as `echo c > /proc/sysrq-trigger`), are debugged with gdb, gdb fails to show the backtrace correctly. On further analysis, it was found that it was because of mismatch between r1 and NIP. GDB uses NIP to get current function symbol and uses corresponding debug info of that function to unwind previous frames, but due to the mismatching r1 and NIP, the unwinding does not work, and it fails to unwind to the 2nd frame and hence does not show the backtrace. GDB backtrace with vmcore of kernel without this patch: --------- (gdb) bt #0 0xc0000000002a53e8 in crash_setup_regs (oldregs=<optimized out>, newregs=0xc000000004f8f8d8) at ./arch/powerpc/include/asm/kexec.h:69 #1 __crash_kexec (regs=<optimized out>) at kernel/kexec_core.c:974 #2 0x0000000000000063 in ?? () #3 0xc000000003579320 in ?? () --------- Further analysis revealed that the mismatch occurred because "ppc_save_regs" was saving the previous stack's SP instead of the current r1. This patch fixes this by storing current r1 in the saved pt_regs. GDB backtrace with vmcore of patched kernel: -------- (gdb) bt #0 0xc0000000002a53e8 in crash_setup_regs (oldregs=0x0, newregs=0xc00000000670b8d8) at ./arch/powerpc/include/asm/kexec.h:69 #1 __crash_kexec (regs=regs@entry=0x0) at kernel/kexec_core.c:974 #2 0xc000000000168918 in panic (fmt=fmt@entry=0xc000000001654a60 "sysrq triggered crash\n") at kernel/panic.c:358 #3 0xc000000000b735f8 in sysrq_handle_crash (key=<optimized out>) at drivers/tty/sysrq.c:155 #4 0xc000000000b742cc in __handle_sysrq (key=key@entry=99, check_mask=check_mask@entry=false) at drivers/tty/sysrq.c:602 #5 0xc000000000b7506c in write_sysrq_trigger (file=<optimized out>, buf=<optimized out>, count=2, ppos=<optimized out>) at drivers/tty/sysrq.c:1163 #6 0xc00000000069a7bc in pde_write (ppos=<optimized out>, count=<optimized out>, buf=<optimized out>, file=<optimized out>, pde=0xc00000000362cb40) at fs/proc/inode.c:340 #7 proc_reg_write (file=<optimized out>, buf=<optimized out>, count=<optimized out>, ppos=<optimized out>) at fs/proc/inode.c:352 #8 0xc0000000005b3bbc in vfs_write (file=file@entry=0xc000000006aa6b00, buf=buf@entry=0x61f498b4f60 <error: Cannot access memory at address 0x61f498b4f60>, count=count@entry=2, pos=pos@entry=0xc00000000670bda0) at fs/read_write.c:582 #9 0xc0000000005b4264 in ksys_write (fd=<optimized out>, buf=0x61f498b4f60 <error: Cannot access memory at address 0x61f498b4f60>, count=2) at fs/read_write.c:637 #10 0xc00000000002ea2c in system_call_exception (regs=0xc00000000670be80, r0=<optimized out>) at arch/powerpc/kernel/syscall.c:171 #11 0xc00000000000c270 in system_call_vectored_common () at arch/powerpc/kernel/interrupt_64.S:192 -------- Nick adds: So this now saves regs as though it was an interrupt taken in the caller, at the instruction after the call to ppc_save_regs, whereas previously the NIP was there, but R1 came from the caller's caller and that mismatch is what causes gdb's dwarf unwinder to go haywire. Signed-off-by: Aditya Gupta <adityag@linux.ibm.com> Fixes: d16a58f8854b1 ("powerpc: Improve ppc_save_regs()") Reivewed-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20230615091047.90433-1-adityag@linux.ibm.com Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-07-19powerpc: simplify ppc_save_regsNicholas Piggin
[ Upstream commit 37195b820d32c23bdefce3f460ed7de48a57e5e4 ] Adjust the pt_regs pointer so the interrupt frame offsets can be used to save registers. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20221127124942.1665522-7-npiggin@gmail.com Stable-dep-of: b684c09f09e7 ("powerpc: update ppc_save_regs to save current r1 in pt_regs") Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-07-19powerpc/powernv/sriov: perform null check on iov before dereferencing iovColin Ian King
[ Upstream commit f4f913c980bc6abe0ccfe88fe3909c125afe4a2d ] Currently pointer iov is being dereferenced before the null check of iov which can lead to null pointer dereference errors. Fix this by moving the iov null check before the dereferencing. Detected using cppcheck static analysis: linux/arch/powerpc/platforms/powernv/pci-sriov.c:597:12: warning: Either the condition '!iov' is redundant or there is possible null pointer dereference: iov. [nullPointerRedundantCheck] num_vfs = iov->num_vfs; ^ Fixes: 052da31d45fc ("powerpc/powernv/sriov: De-indent setup and teardown") Signed-off-by: Colin Ian King <colin.i.king@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20230608095849.1147969-1-colin.i.king@gmail.com Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-07-19powerpc/64s: Fix VAS mm use after freeNicholas Piggin
[ Upstream commit b4bda59b47879cce38a6ec5a01cd3cac702b5331 ] The refcount on mm is dropped before the coprocessor is detached. Reported-by: Sachin Sant <sachinp@linux.ibm.com> Fixes: 7bc6f71bdff5f ("powerpc/vas: Define and use common vas_window struct") Fixes: b22f2d88e435c ("powerpc/pseries/vas: Integrate API with open/close windows") Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Tested-by: Sachin Sant <sachinp@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20230607101024.14559-1-npiggin@gmail.com Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-07-19powerpc/signal32: Force inlining of __unsafe_save_user_regs() and ↵Christophe Leroy
save_tm_user_regs_unsafe() [ Upstream commit a03b1a0b19398a47489fdcef02ec19c2ba05a15d ] Looking at generated code for handle_signal32() shows calls to a function called __unsafe_save_user_regs.constprop.0 while user access is open. And that __unsafe_save_user_regs.constprop.0 function has two nops at the begining, allowing it to be traced, which is unexpected during user access open window. The solution could be to mark __unsafe_save_user_regs() no trace, but to be on the safe side the most efficient is to flag it __always_inline as already done for function __unsafe_restore_general_regs(). The function is relatively small and only called twice, so the size increase will remain in the noise. Do the same with save_tm_user_regs_unsafe() as it may suffer the same issue. Fixes: ef75e7318294 ("powerpc/signal32: Transform save_user_regs() and save_tm_user_regs() in 'unsafe' version") Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/7e469c8f01860a69c1ada3ca6a5e2aa65f0f74b2.1685955220.git.christophe.leroy@csgroup.eu Signed-off-by: Sasha Levin <sashal@kernel.org>