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2021-02-23Merge tag 'modules-for-v5.12' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux Pull module updates from Jessica Yu: - Retire EXPORT_UNUSED_SYMBOL() and EXPORT_SYMBOL_GPL_FUTURE(). These export types were introduced between 2006 - 2008. All the of the unused symbols have been long removed and gpl future symbols were converted to gpl quite a long time ago, and I don't believe these export types have been used ever since. So, I think it should be safe to retire those export types now (Christoph Hellwig) - Refactor and clean up some aged code cruft in the module loader (Christoph Hellwig) - Build {,module_}kallsyms_on_each_symbol only when livepatching is enabled, as it is the only caller (Christoph Hellwig) - Unexport find_module() and module_mutex and fix the last module callers to not rely on these anymore. Make module_mutex internal to the module loader (Christoph Hellwig) - Harden ELF checks on module load and validate ELF structures before checking the module signature (Frank van der Linden) - Fix undefined symbol warning for clang (Fangrui Song) - Fix smatch warning (Dan Carpenter) * tag 'modules-for-v5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux: module: potential uninitialized return in module_kallsyms_on_each_symbol() module: remove EXPORT_UNUSED_SYMBOL* module: remove EXPORT_SYMBOL_GPL_FUTURE module: move struct symsearch to module.c module: pass struct find_symbol_args to find_symbol module: merge each_symbol_section into find_symbol module: remove each_symbol_in_section module: mark module_mutex static kallsyms: only build {,module_}kallsyms_on_each_symbol when required kallsyms: refactor {,module_}kallsyms_on_each_symbol module: use RCU to synchronize find_module module: unexport find_module and module_mutex drm: remove drm_fb_helper_modinit powerpc/powernv: remove get_cxl_module module: harden ELF info handling module: Ignore _GLOBAL_OFFSET_TABLE_ when warning for undefined symbols
2021-02-22Merge tag 'powerpc-5.12-1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc updates from Michael Ellerman: - A large series adding wrappers for our interrupt handlers, so that irq/nmi/user tracking can be isolated in the wrappers rather than spread in each handler. - Conversion of the 32-bit syscall handling into C. - A series from Nick to streamline our TLB flushing when using the Radix MMU. - Switch to using queued spinlocks by default for 64-bit server CPUs. - A rework of our PCI probing so that it happens later in boot, when more generic infrastructure is available. - Two small fixes to allow 32-bit little-endian processes to run on 64-bit kernels. - Other smaller features, fixes & cleanups. Thanks to: Alexey Kardashevskiy, Ananth N Mavinakayanahalli, Aneesh Kumar K.V, Athira Rajeev, Bhaskar Chowdhury, Cédric Le Goater, Chengyang Fan, Christophe Leroy, Christopher M. Riedl, Fabiano Rosas, Florian Fainelli, Frederic Barrat, Ganesh Goudar, Hari Bathini, Jiapeng Chong, Joseph J Allen, Kajol Jain, Markus Elfring, Michal Suchanek, Nathan Lynch, Naveen N. Rao, Nicholas Piggin, Oliver O'Halloran, Pingfan Liu, Po-Hsu Lin, Qian Cai, Ram Pai, Randy Dunlap, Sandipan Das, Stephen Rothwell, Tyrel Datwyler, Will Springer, Yury Norov, and Zheng Yongjun. * tag 'powerpc-5.12-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (188 commits) powerpc/perf: Adds support for programming of Thresholding in P10 powerpc/pci: Remove unimplemented prototypes powerpc/uaccess: Merge raw_copy_to_user_allowed() into raw_copy_to_user() powerpc/uaccess: Merge __put_user_size_allowed() into __put_user_size() powerpc/uaccess: get rid of small constant size cases in raw_copy_{to,from}_user() powerpc/64: Fix stack trace not displaying final frame powerpc/time: Remove get_tbl() powerpc/time: Avoid using get_tbl() spi: mpc52xx: Avoid using get_tbl() powerpc/syscall: Avoid storing 'current' in another pointer powerpc/32: Handle bookE debugging in C in syscall entry/exit powerpc/syscall: Do not check unsupported scv vector on PPC32 powerpc/32: Remove the counter in global_dbcr0 powerpc/32: Remove verification of MSR_PR on syscall in the ASM entry powerpc/syscall: implement system call entry/exit logic in C for PPC32 powerpc/32: Always save non volatile GPRs at syscall entry powerpc/syscall: Change condition to check MSR_RI powerpc/syscall: Save r3 in regs->orig_r3 powerpc/syscall: Use is_compat_task() powerpc/syscall: Make interrupt.c buildable on PPC32 ...
2021-02-11powerpc/mm: Remove dcache flush from memory remove.Aneesh Kumar K.V
We added dcache flush on memory add/remove in commit fb5924fddf9e ("powerpc/mm: Flush cache on memory hot(un)plug") to handle crashes on GPU hotplug. Instead of adding dcache flush in generic memory add/remove routine which is used even for regular memory, we should handle these devices specific flush in the device driver code. memtrace did handle this in the driver and that was removed by commit 7fd6641de28f ("powerpc/powernv/memtrace: Let the arch hotunplug code flush cache"). This patch reverts that commit. The dcache flush in memory add was removed by commit ea458effa88e ("powerpc: Don't flush caches when adding memory") which I don't think is correct. The reason why we require dcache flush in memtrace is to make sure we don't have a dirty cache when we remap a pfn to cache inhibited. We should do that when the memtrace module removes the memory and make the pfn available for HTM traces to map it as cache inhibited. The other device mentioned in commit fb5924fddf9e ("powerpc/mm: Flush cache on memory hot(un)plug") is nvlink device with coherent memory. The support for that was removed in commit 7eb3cf761927 ("powerpc/powernv: remove unused NPU DMA code") and commit 25b2995a35b6 ("mm: remove MEMORY_DEVICE_PUBLIC support") Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20210203045812.234439-3-aneesh.kumar@linux.ibm.com
2021-02-11powerpc/powernv/pci: Use kzalloc() for phb related allocationsMichael Ellerman
As part of commit fbbefb320214 ("powerpc/pci: Move PHB discovery for PCI_DN using platforms"), I switched some allocations from memblock_alloc() to kmalloc(), otherwise memblock would warn that it was being called after slab init. However I missed that the code relied on the allocations being zeroed, without which we could end up crashing: pci_bus 0000:00: busn_res: [bus 00-ff] end is updated to ff BUG: Unable to handle kernel data access on read at 0x6b6b6b6b6b6b6af7 Faulting instruction address: 0xc0000000000dbc90 Oops: Kernel access of bad area, sig: 11 [#1] LE PAGE_SIZE=64K MMU=Hash SMP NR_CPUS=2048 NUMA PowerNV ... NIP pnv_ioda_get_pe_state+0xe0/0x1d0 LR pnv_ioda_get_pe_state+0xb4/0x1d0 Call Trace: pnv_ioda_get_pe_state+0xb4/0x1d0 (unreliable) pnv_pci_config_check_eeh.isra.9+0x78/0x270 pnv_pci_read_config+0xf8/0x160 pci_bus_read_config_dword+0xa4/0x120 pci_bus_generic_read_dev_vendor_id+0x54/0x270 pci_scan_single_device+0xb8/0x140 pci_scan_slot+0x80/0x1b0 pci_scan_child_bus_extend+0x94/0x490 pcibios_scan_phb+0x1f8/0x3c0 pcibios_init+0x8c/0x12c do_one_initcall+0x94/0x510 kernel_init_freeable+0x35c/0x3fc kernel_init+0x2c/0x168 ret_from_kernel_thread+0x5c/0x70 Switch them to kzalloc(). Fixes: fbbefb320214 ("powerpc/pci: Move PHB discovery for PCI_DN using platforms") Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20210211112749.3410771-1-mpe@ellerman.id.au
2021-02-09powerpc: remove unneeded semicolonsChengyang Fan
Remove superfluous semicolons after function definitions. Signed-off-by: Chengyang Fan <cy.fan@huawei.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20210125095338.1719405-1-cy.fan@huawei.com
2021-02-09powerpc: convert interrupt handlers to use wrappersNicholas Piggin
Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20210130130852.2952424-29-npiggin@gmail.com
2021-02-09powerpc: introduce die_mceNicholas Piggin
As explained by commit daf00ae71dad ("powerpc/traps: restore recoverability of machine_check interrupts"), die() can't be called from within nmi_enter to nicely kill a process context that was interrupted. nmi_exit must be called first. This adds a function die_mce which takes care of this for machine check handlers. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20210130130852.2952424-24-npiggin@gmail.com
2021-02-09powerpc/pci: Move PHB discovery for PCI_DN using platformsOliver O'Halloran
Make powernv, pseries, powermac and maple use ppc_mc.discover_phbs. These platforms need to be done together because they all depend on pci_dn's being created from the DT. The pci_dn contains a pointer to the relevant pci_controller so they need to be created after the pci_controller structures are available, but before PCI devices are scanned. Currently this ordering is provided by initcalls and the sequence is: 1. PHBs are discovered (setup_arch) (early boot, pre-initcalls) 2. pci_dn are created from the unflattended DT (core initcall) 3. PHBs are scanned pcibios_init() (subsys initcall) The new ppc_md.discover_phbs() function is also a core_initcall so we can't guarantee ordering between the creation of pci_controllers and the creation of pci_dn's which require a pci_controller. We could use the postcore, or core_sync initcall levels, but it's cleaner to just move the pci_dn setup into the per-PHB inits which occur inside of .discover_phb() for these platforms. This brings the boot-time path in line with the PHB hotplug path that is used for pseries DLPAR operations too. Signed-off-by: Oliver O'Halloran <oohall@gmail.com> [mpe: Squash powermac & maple in to avoid breakage those platforms, convert memblock allocs to use kmalloc to avoid warnings] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20201103043523.916109-2-oohall@gmail.com
2021-02-08powerpc/powernv: remove get_cxl_moduleChristoph Hellwig
The static inline get_cxl_module function is entirely unused since commit 8bf6b91a5125a ("Revert "powerpc/powernv: Add support for the cxl kernel api on the real phb"), so remove it. Acked-by: Michael Ellerman <mpe@ellerman.id.au> Reviewed-by: Andrew Donnellan <ajd@linux.ibm.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jessica Yu <jeyu@kernel.org>
2021-01-31powerpc/powernv/pci: Drop pnv_phb->initializedOliver O'Halloran
The pnv_phb->initialized flag is an odd beast. It was added back in 2012 in commit db1266c85261 ("powerpc/powernv: Skip check on PE if necessary") to allow devices to be enabled even if the device had not yet been assigned to a PE. Allowing the device to be enabled before the PE is configured may cause spurious EEH events since none of the IOMMU context has been setup. I'm not entirely sure why this was ever necessary. My best guess is that it was an workaround for a bug or some other undesireable behaviour from the PCI core. Either way, it's unnecessary now since as of commit dc3d8f85bb57 ("powerpc/powernv/pci: Re-work bus PE configuration") we can guarantee that the PE will be configured before the PCI core will allow drivers to bind to the device. It's also worth pointing out that the ->initialized flag is only set in pnv_pci_ioda_create_dbgfs(). That function has its entire body wrapped in #ifdef CONFIG_DEBUG_FS. As a result, for kernels built without debugfs (i.e. petitboot) the other checks in pnv_pci_enable_device_hook() are bypassed entirely. Signed-off-by: Oliver O'Halloran <oohall@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200902013657.1753830-1-oohall@gmail.com
2021-01-31powerpc/powernv/pci: fix a RCU-list lockQian Cai
It is unsafe to traverse tbl->it_group_list without the RCU read lock. WARNING: suspicious RCU usage 5.7.0-rc4-next-20200508 #1 Not tainted ----------------------------- arch/powerpc/platforms/powernv/pci-ioda-tce.c:355 RCU-list traversed in non-reader section!! other info that might help us debug this: rcu_scheduler_active = 2, debug_locks = 1 3 locks held by qemu-kvm/4305: #0: c000000bc3fe6988 (&container->group_lock){++++}-{3:3}, at: vfio_fops_unl_ioctl+0x108/0x410 [vfio] #1: c00800000fcc7400 (&vfio.iommu_drivers_lock){+.+.}-{3:3}, at: vfio_fops_unl_ioctl+0x148/0x410 [vfio] #2: c000000bc3fe4d68 (&container->lock){+.+.}-{3:3}, at: tce_iommu_attach_group+0x3c/0x4f0 [vfio_iommu_spapr_tce] stack backtrace: CPU: 4 PID: 4305 Comm: qemu-kvm Not tainted 5.7.0-rc4-next-20200508 #1 Call Trace: [c0000010f29afa60] [c0000000007154c8] dump_stack+0xfc/0x174 (unreliable) [c0000010f29afab0] [c0000000001d8ff0] lockdep_rcu_suspicious+0x140/0x164 [c0000010f29afb30] [c0000000000dae2c] pnv_pci_unlink_table_and_group+0x11c/0x200 [c0000010f29afb70] [c0000000000d4a34] pnv_pci_ioda2_unset_window+0xc4/0x190 [c0000010f29afbf0] [c0000000000d4b4c] pnv_ioda2_take_ownership+0x4c/0xd0 [c0000010f29afc30] [c00800000fd60ee0] tce_iommu_attach_group+0x2c8/0x4f0 [vfio_iommu_spapr_tce] [c0000010f29afcd0] [c00800000fcc11a0] vfio_fops_unl_ioctl+0x238/0x410 [vfio] [c0000010f29afd50] [c0000000005430a8] ksys_ioctl+0xd8/0x130 [c0000010f29afda0] [c000000000543128] sys_ioctl+0x28/0x40 [c0000010f29afdc0] [c000000000038af4] system_call_exception+0x114/0x1e0 [c0000010f29afe20] [c00000000000c8f0] system_call_common+0xf0/0x278 Signed-off-by: Qian Cai <cai@lca.pw> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200510051347.1906-1-cai@lca.pw
2021-01-30powerpc/vas: Fix IRQ name allocationCédric Le Goater
The VAS device allocates a generic interrupt to handle page faults but the IRQ name doesn't show under /proc. This is because it's on stack. Allocate the name. Signed-off-by: Cédric Le Goater <clg@kaod.org> Acked-by: Haren Myneni <haren@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20201212142707.2102141-1-clg@kaod.org
2021-01-06elf_prstatus: collect the common part (everything before pr_reg) into a structAl Viro
Preparations to doing i386 compat elf_prstatus sanely - rather than duplicating the beginning of compat_elf_prstatus, take these fields into a separate structure (compat_elf_prstatus_common), so that it could be reused. Due to the incestous relationship between binfmt_elf.c and compat_binfmt_elf.c we need the same shape change done to native struct elf_prstatus, gathering the fields prior to pr_reg into a new structure (struct elf_prstatus_common). Fortunately, offset of pr_reg is always a multiple of 16 with no padding right before it, so it's possible to turn all the stuff prior to it into a single member without disturbing the layout. [build fix from Geert Uytterhoeven folded in] Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-12-17Merge tag 'powerpc-5.11-1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc updates from Michael Ellerman: - Switch to the generic C VDSO, as well as some cleanups of our VDSO setup/handling code. - Support for KUAP (Kernel User Access Prevention) on systems using the hashed page table MMU, using memory protection keys. - Better handling of PowerVM SMT8 systems where all threads of a core do not share an L2, allowing the scheduler to make better scheduling decisions. - Further improvements to our machine check handling. - Show registers when unwinding interrupt frames during stack traces. - Improvements to our pseries (PowerVM) partition migration code. - Several series from Christophe refactoring and cleaning up various parts of the 32-bit code. - Other smaller features, fixes & cleanups. Thanks to: Alan Modra, Alexey Kardashevskiy, Andrew Donnellan, Aneesh Kumar K.V, Ard Biesheuvel, Athira Rajeev, Balamuruhan S, Bill Wendling, Cédric Le Goater, Christophe Leroy, Christophe Lombard, Colin Ian King, Daniel Axtens, David Hildenbrand, Frederic Barrat, Ganesh Goudar, Gautham R. Shenoy, Geert Uytterhoeven, Giuseppe Sacco, Greg Kurz, Harish, Jan Kratochvil, Jordan Niethe, Kaixu Xia, Laurent Dufour, Leonardo Bras, Madhavan Srinivasan, Mahesh Salgaonkar, Mathieu Desnoyers, Nathan Lynch, Nicholas Piggin, Oleg Nesterov, Oliver O'Halloran, Oscar Salvador, Po-Hsu Lin, Qian Cai, Qinglang Miao, Randy Dunlap, Ravi Bangoria, Sachin Sant, Sandipan Das, Sebastian Andrzej Siewior , Segher Boessenkool, Srikar Dronamraju, Tyrel Datwyler, Uwe Kleine-König, Vincent Stehlé, Youling Tang, and Zhang Xiaoxu. * tag 'powerpc-5.11-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (304 commits) powerpc/32s: Fix cleanup_cpu_mmu_context() compile bug powerpc: Add config fragment for disabling -Werror powerpc/configs: Add ppc64le_allnoconfig target powerpc/powernv: Rate limit opal-elog read failure message powerpc/pseries/memhotplug: Quieten some DLPAR operations powerpc/ps3: use dma_mapping_error() powerpc: force inlining of csum_partial() to avoid multiple csum_partial() with GCC10 powerpc/perf: Fix Threshold Event Counter Multiplier width for P10 powerpc/mm: Fix hugetlb_free_pmd_range() and hugetlb_free_pud_range() KVM: PPC: Book3S HV: Fix mask size for emulated msgsndp KVM: PPC: fix comparison to bool warning KVM: PPC: Book3S: Assign boolean values to a bool variable powerpc: Inline setup_kup() powerpc/64s: Mark the kuap/kuep functions non __init KVM: PPC: Book3S HV: XIVE: Add a comment regarding VP numbering powerpc/xive: Improve error reporting of OPAL calls powerpc/xive: Simplify xive_do_source_eoi() powerpc/xive: Remove P9 DD1 flag XIVE_IRQ_FLAG_EOI_FW powerpc/xive: Remove P9 DD1 flag XIVE_IRQ_FLAG_MASK_FW powerpc/xive: Remove P9 DD1 flag XIVE_IRQ_FLAG_SHIFT_BUG ...
2020-12-15powerpc/powernv: Rate limit opal-elog read failure messageAndrew Donnellan
Sometimes we can't read an error log from OPAL, and we print an error message accordingly. But the OPAL userspace tools seem to like retrying a lot, in which case we flood the kernel log with a lot of messages. Change pr_err() to pr_err_ratelimited() to help with this. Signed-off-by: Andrew Donnellan <ajd@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20201211021140.28402-1-ajd@linux.ibm.com
2020-12-09powerpc/64: irq replay remove decrementer overflow checkNicholas Piggin
This is way to catch some cases of decrementer overflow, when the decrementer has underflowed an odd number of times, while MSR[EE] was disabled. With a typical small decrementer, a timer that fires when MSR[EE] is disabled will be "lost" if MSR[EE] remains disabled for between 4.3 and 8.6 seconds after the timer expires. In any case, the decrementer interrupt would be taken at 8.6 seconds and the timer would be found at that point. So this check is for catching extreme latency events, and it prevents those latencies from being a further few seconds long. It's not obvious this is a good tradeoff. This is already a watchdog magnitude event and that situation is not improved a significantly with this check. For large decrementers, it's useless. Therefore remove this check, which avoids a mftb when enabling hard disabled interrupts (e.g., when enabling after coming from hardware interrupt handlers). Perhaps more importantly, it also removes the clunky MSR[EE] vs PACA_IRQ_HARD_DIS incoherency in soft-interrupt replay which simplifies the code. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20201107014336.2337337-1-npiggin@gmail.com
2020-12-07powerpc/powernv/idle: Restore CIABR after idle for Power9Jordan Niethe
On Power9, CIABR is lost after idle. This means that instruction breakpoints set by xmon which use CIABR do not work. Fix this by restoring CIABR after idle. Signed-off-by: Jordan Niethe <jniethe5@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20201207010519.15597-2-jniethe5@gmail.com
2020-12-04powerpc/powernv/npu: Do not attempt NPU2 setup on POWER8NVL NPUAlexey Kardashevskiy
We execute certain NPU2 setup code (such as mapping an LPID to a device in NPU2) unconditionally if an Nvlink bridge is detected. However this cannot succeed on POWER8NVL machines and errors appear in dmesg. This is harmless as skiboot returns an error and the only place we check it is vfio-pci but that code does not get called on P8+ either. This adds a check if pnv_npu2_xxx helpers are called on a machine with NPU2 which initializes pnv_phb::npu in pnv_npu2_init(); pnv_phb::npu==NULL on POWER8/NVL (Naples). While at this, fix NULL derefencing in pnv_npu_peers_take_ownership/ pnv_npu_peers_release_ownership which occurs when GPUs on mentioned P8s cause EEH which happens if "vfio-pci" disables devices using the D3 power state; the vfio-pci's disable_idle_d3 module parameter controls this and must be set on Naples. The EEH handling clears the entire pnv_ioda_pe struct in pnv_ioda_free_pe() hence the NULL derefencing. We cannot recover from that but at least we stop crashing. Tested on - POWER9 pvr=004e1201, Ubuntu 19.04 host, Ubuntu 18.04 vm, NVIDIA GV100 10de:1db1 driver 418.39 - POWER8 pvr=004c0100, RHEL 7.6 host, Ubuntu 16.10 vm, NVIDIA P100 10de:15f9 driver 396.47 Fixes: 1b785611e119 ("powerpc/powernv/npu: Add release_ownership hook") Cc: stable@vger.kernel.org # 5.0 Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20201122073828.15446-1-aik@ozlabs.ru
2020-12-04powernv/pci: Print an error when device enable is blockedOliver O'Halloran
If the platform decides to block enabling the device nothing is printed currently. This can lead to some confusion since the dmesg output will usually print an error with no context e.g. e1000e: probe of 0022:01:00.0 failed with error -22 This shouldn't be spammy since pci_enable_device() already prints a messages when it succeeds. Signed-off-by: Oliver O'Halloran <oohall@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200409061337.9187-1-oohall@gmail.com
2020-12-04ocxl: Initiate a TLB invalidate commandChristophe Lombard
When a TLB Invalidate is required for the Logical Partition, the following sequence has to be performed: 1. Load MMIO ATSD AVA register with the necessary value, if required. 2. Write the MMIO ATSD launch register to initiate the TLB Invalidate command. 3. Poll the MMIO ATSD status register to determine when the TLB Invalidate has been completed. Signed-off-by: Christophe Lombard <clombard@linux.vnet.ibm.com> Acked-by: Frederic Barrat <fbarrat@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20201125155013.39955-3-clombard@linux.vnet.ibm.com
2020-12-04ocxl: Assign a register set to a Logical PartitionChristophe Lombard
Platform specific function to assign a register set to a Logical Partition. The "ibm,mmio-atsd" property, provided by the firmware, contains the 16 base ATSD physical addresses (ATSD0 through ATSD15) of the set of MMIO registers (XTS MMIO ATSDx LPARID/AVA/launch/status register). For the time being, the ATSD0 set of registers is used by default. Signed-off-by: Christophe Lombard <clombard@linux.vnet.ibm.com> Acked-by: Frederic Barrat <fbarrat@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20201125155013.39955-2-clombard@linux.vnet.ibm.com
2020-12-04powerpc/64s/powernv: Ratelimit harmless HMI error printingNicholas Piggin
Harmless HMI errors can be triggered by guests in some cases, and don't contain much useful information anyway. Ratelimit these to avoid flooding the console/logs. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> [mpe: Use dedicated ratelimit state, not printk_ratelimit()] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20201128070728.825934-6-npiggin@gmail.com
2020-12-02powerpc/64s/powernv: Fix memory corruption when saving SLB entries on MCENicholas Piggin
This can be hit by an HPT guest running on an HPT host and bring down the host, so it's quite important to fix. Fixes: 7290f3b3d3e6 ("powerpc/64s/powernv: machine check dump SLB contents") Cc: stable@vger.kernel.org # v5.4+ Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Acked-by: Mahesh Salgaonkar <mahesh@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20201128070728.825934-2-npiggin@gmail.com
2020-11-27powerpc/64s: Trim offlined CPUs from mm_cpumasksNicholas Piggin
When offlining a CPU, powerpc/64s does not flush TLBs, rather it just leaves the CPU set in mm_cpumasks, so it continues to receive TLBIEs to manage its TLBs. However the exit_flush_lazy_tlbs() function expects that after returning, all CPUs (except self) have flushed TLBs for that mm, in which case TLBIEL can be used for this flush. This breaks for offline CPUs because they don't get the IPI to flush their TLB. This can lead to stale translations. Fix this by clearing the CPU from mm_cpumasks, then flushing all TLBs before going offline. These offlined CPU bits stuck in the cpumask also prevents the cpumask from being trimmed back to local mode, which means continual broadcast IPIs or TLBIEs are needed for TLB flushing. This patch prevents that situation too. A cast of many were involved in working this out, but in particular Milton, Aneesh, Paul made key discoveries. Fixes: 0cef77c7798a7 ("powerpc/64s/radix: flush remote CPUs out of single-threaded mm_cpumask") Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Debugged-by: Milton Miller <miltonm@us.ibm.com> Debugged-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Debugged-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20201126102530.691335-5-npiggin@gmail.com
2020-11-25Merge branch 'fixes' into nextMichael Ellerman
Merge our fixes branch, in particular to bring in the changes for the entry/uaccess flush.
2020-11-19powerpc/64s: rename pnv|pseries_setup_rfi_flush to _setup_security_mitigationsDaniel Axtens
pseries|pnv_setup_rfi_flush already does the count cache flush setup, and we just added entry and uaccess flushes. So the name is not very accurate any more. In both platforms we then also immediately setup the STF flush. Rename them to _setup_security_mitigations and fold the STF flush in. Signed-off-by: Daniel Axtens <dja@axtens.net> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2020-11-19powerpc/64s: flush L1D after user accessesNicholas Piggin
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: Michael Ellerman <mpe@ellerman.id.au>
2020-11-19powerpc/64s: flush L1D on kernel entryNicholas Piggin
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: Michael Ellerman <mpe@ellerman.id.au>
2020-11-19powernv/memtrace: don't abuse memory hot(un)plug infrastructure for memory ↵David Hildenbrand
allocations Let's use alloc_contig_pages() for allocating memory and remove the linear mapping manually via arch_remove_linear_mapping(). Mark all pages PG_offline, such that they will definitely not get touched - e.g., when hibernating. When freeing memory, try to revert what we did. The original idea was discussed in: https://lkml.kernel.org/r/48340e96-7e6b-736f-9e23-d3111b915b6e@redhat.com This is similar to CONFIG_DEBUG_PAGEALLOC handling on other architectures, whereby only single pages are unmapped from the linear mapping. Let's mimic what memory hot(un)plug would do with the linear mapping. We now need MEMORY_HOTPLUG and CONTIG_ALLOC as dependencies. Add a TODO that we want to use __GFP_ZERO for clearing once alloc_contig_pages() understands that. Tested with in QEMU/TCG with 10 GiB of main memory: [root@localhost ~]# echo 0x40000000 > /sys/kernel/debug/powerpc/memtrace/enable [ 105.903043][ T1080] memtrace: Allocated trace memory on node 0 at 0x0000000080000000 [root@localhost ~]# echo 0x40000000 > /sys/kernel/debug/powerpc/memtrace/enable [ 145.042493][ T1080] radix-mmu: Mapped 0x0000000080000000-0x00000000c0000000 with 64.0 KiB pages [ 145.049019][ T1080] memtrace: Freed trace memory back on node 0 [ 145.333960][ T1080] memtrace: Allocated trace memory on node 0 at 0x0000000080000000 [root@localhost ~]# echo 0x80000000 > /sys/kernel/debug/powerpc/memtrace/enable [ 213.606916][ T1080] radix-mmu: Mapped 0x0000000080000000-0x00000000c0000000 with 64.0 KiB pages [ 213.613855][ T1080] memtrace: Freed trace memory back on node 0 [ 214.185094][ T1080] memtrace: Allocated trace memory on node 0 at 0x0000000080000000 [root@localhost ~]# echo 0x100000000 > /sys/kernel/debug/powerpc/memtrace/enable [ 234.874872][ T1080] radix-mmu: Mapped 0x0000000080000000-0x0000000100000000 with 64.0 KiB pages [ 234.886974][ T1080] memtrace: Freed trace memory back on node 0 [ 234.890153][ T1080] memtrace: Failed to allocate trace memory on node 0 [root@localhost ~]# echo 0x40000000 > /sys/kernel/debug/powerpc/memtrace/enable [ 259.490196][ T1080] memtrace: Allocated trace memory on node 0 at 0x0000000080000000 I also made sure allocated memory is properly zeroed. Note 1: We currently won't be allocating from ZONE_MOVABLE - because our pages are not movable. However, as we don't run with any memory hot(un)plug mechanism around, we could make an exception to increase the chance of allocations succeeding. Note 2: PG_reserved isn't sufficient. E.g., kernel_page_present() used along PG_reserved in hibernation code will always return "true" on powerpc, resulting in the pages getting touched. It's too generic - e.g., indicates boot allocations. Note 3: For now, we keep using memory_block_size_bytes() as minimum granularity. Suggested-by: Michal Hocko <mhocko@kernel.org> Signed-off-by: David Hildenbrand <david@redhat.com> Reviewed-by: Oscar Salvador <osalvador@suse.de> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20201111145322.15793-9-david@redhat.com
2020-11-19powerpc/powernv/memtrace: Fix crashing the kernel when enabling concurrentlyDavid Hildenbrand
It's very easy to crash the kernel right now by simply trying to enable memtrace concurrently, hammering on the "enable" interface loop.sh: #!/bin/bash dmesg --console-off while true; do echo 0x40000000 > /sys/kernel/debug/powerpc/memtrace/enable done [root@localhost ~]# loop.sh & [root@localhost ~]# loop.sh & Resulting quickly in a kernel crash. Let's properly protect using a mutex. Fixes: 9d5171a8f248 ("powerpc/powernv: Enable removal of memory for in memory tracing") Cc: stable@vger.kernel.org# v4.14+ Signed-off-by: David Hildenbrand <david@redhat.com> Reviewed-by: Oscar Salvador <osalvador@suse.de> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20201111145322.15793-3-david@redhat.com
2020-11-19powerpc/powernv/memtrace: Don't leak kernel memory to user spaceDavid Hildenbrand
We currently leak kernel memory to user space, because memory offlining doesn't do any implicit clearing of memory and we are missing explicit clearing of memory. Let's keep it simple and clear pages before removing the linear mapping. Reproduced in QEMU/TCG with 10 GiB of main memory: [root@localhost ~]# dd obs=9G if=/dev/urandom of=/dev/null [... wait until "free -m" used counter no longer changes and cancel] 19665802+0 records in 1+0 records out 9663676416 bytes (9.7 GB, 9.0 GiB) copied, 135.548 s, 71.3 MB/s [root@localhost ~]# cat /sys/devices/system/memory/block_size_bytes 40000000 [root@localhost ~]# echo 0x40000000 > /sys/kernel/debug/powerpc/memtrace/enable [ 402.978663][ T1086] page:000000001bc4bc74 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x24900 [ 402.980063][ T1086] flags: 0x7ffff000001000(reserved) [ 402.980415][ T1086] raw: 007ffff000001000 c00c000000924008 c00c000000924008 0000000000000000 [ 402.980627][ T1086] raw: 0000000000000000 0000000000000000 00000001ffffffff 0000000000000000 [ 402.980845][ T1086] page dumped because: unmovable page [ 402.989608][ T1086] Offlined Pages 16384 [ 403.324155][ T1086] memtrace: Allocated trace memory on node 0 at 0x0000000200000000 Before this patch: [root@localhost ~]# hexdump -C /sys/kernel/debug/powerpc/memtrace/00000000/trace | head 00000000 c8 25 72 51 4d 26 36 c5 5c c2 56 15 d5 1a cd 10 |.%rQM&6.\.V.....| 00000010 19 b9 50 b2 cb e3 60 b8 ec 0a f3 ec 4b 3c 39 f0 |..P...`.....K<9.|$ 00000020 4e 5a 4c cf bd 26 19 ff 37 79 13 67 24 b7 b8 57 |NZL..&..7y.g$..W|$ 00000030 98 3e f5 be 6f 14 6a bd a4 52 bc 6e e9 e0 c1 5d |.>..o.j..R.n...]|$ 00000040 76 b3 ae b5 88 d7 da e3 64 23 85 2c 10 88 07 b6 |v.......d#.,....|$ 00000050 9a d8 91 de f7 50 27 69 2e 64 9c 6f d3 19 45 79 |.....P'i.d.o..Ey|$ 00000060 6a 6f 8a 61 71 19 1f c7 f1 df 28 26 ca 0f 84 55 |jo.aq.....(&...U|$ 00000070 01 3f be e4 e2 e1 da ff 7b 8c 8e 32 37 b4 24 53 |.?......{..27.$S|$ 00000080 1b 70 30 45 56 e6 8c c4 0e b5 4c fb 9f dd 88 06 |.p0EV.....L.....|$ 00000090 ef c4 18 79 f1 60 b1 5c 79 59 4d f4 36 d7 4a 5c |...y.`.\yYM.6.J\|$ After this patch: [root@localhost ~]# hexdump -C /sys/kernel/debug/powerpc/memtrace/00000000/trace | head 00000000 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 |................| * 40000000 Fixes: 9d5171a8f248 ("powerpc/powernv: Enable removal of memory for in memory tracing") Cc: stable@vger.kernel.org # v4.14+ Reported-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: David Hildenbrand <david@redhat.com> Reviewed-by: Oscar Salvador <osalvador@suse.de> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20201111145322.15793-2-david@redhat.com
2020-11-19powerpc/powernv/sriov: fix unsigned int win compared to less than zeroKaixu Xia
Fix coccicheck warning: arch/powerpc/platforms/powernv/pci-sriov.c:443:7-10: WARNING: Unsigned expression compared with zero: win < 0 arch/powerpc/platforms/powernv/pci-sriov.c:462:7-10: WARNING: Unsigned expression compared with zero: win < 0 Fixes: 39efc03e3ee8 ("powerpc/powernv/sriov: Move M64 BAR allocation into a helper") Reported-by: Tosk Robot <tencent_os_robot@tencent.com> Signed-off-by: Kaixu Xia <kaixuxia@tencent.com> Reviewed-by: Andrew Donnellan <ajd@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/1605007170-22171-1-git-send-email-kaixuxia@tencent.com
2020-10-24Merge tag 'powerpc-5.10-2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc fixes from Michael Ellerman: - A fix for undetected data corruption on Power9 Nimbus <= DD2.1 in the emulation of VSX loads. The affected CPUs were not widely available. - Two fixes for machine check handling in guests under PowerVM. - A fix for our recent changes to SMP setup, when CONFIG_CPUMASK_OFFSTACK=y. - Three fixes for races in the handling of some of our powernv sysfs attributes. - One change to remove TM from the set of Power10 CPU features. - A couple of other minor fixes. Thanks to: Aneesh Kumar K.V, Christophe Leroy, Ganesh Goudar, Jordan Niethe, Mahesh Salgaonkar, Michael Neuling, Oliver O'Halloran, Qian Cai, Srikar Dronamraju, Vasant Hegde. * tag 'powerpc-5.10-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: powerpc/pseries: Avoid using addr_to_pfn in real mode powerpc/uaccess: Don't use "m<>" constraint with GCC 4.9 powerpc/eeh: Fix eeh_dev_check_failure() for PE#0 powerpc/64s: Remove TM from Power10 features selftests/powerpc: Make alignment handler test P9N DD2.1 vector CI load workaround powerpc: Fix undetected data corruption with P9N DD2.1 VSX CI load emulation powerpc/powernv/dump: Handle multiple writes to ack attribute powerpc/powernv/dump: Fix race while processing OPAL dump powerpc/smp: Use GFP_ATOMIC while allocating tmp mask powerpc/smp: Remove unnecessary variable powerpc/mce: Avoid nmi_enter/exit in real mode on pseries hash powerpc/opal_elog: Handle multiple writes to ack attribute
2020-10-19powerpc/powernv/dump: Handle multiple writes to ack attributeVasant Hegde
Even though we use self removing sysfs helper, we still need to make sure we do the final kobject delete conditionally. sysfs_remove_file_self() will handle parallel calls to remove the sysfs attribute file and returns true only in the caller that removed the attribute file. The other parallel callers are returned false. Do the final kobject delete checking the return value of sysfs_remove_file_self(). Signed-off-by: Vasant Hegde <hegdevasant@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20201017164236.264713-1-hegdevasant@linux.vnet.ibm.com
2020-10-19powerpc/powernv/dump: Fix race while processing OPAL dumpVasant Hegde
Every dump reported by OPAL is exported to userspace through a sysfs interface and notified using kobject_uevent(). The userspace daemon (opal_errd) then reads the dump and acknowledges that the dump is saved safely to disk. Once acknowledged the kernel removes the respective sysfs file entry causing respective resources to be released including kobject. However it's possible the userspace daemon may already be scanning dump entries when a new sysfs dump entry is created by the kernel. User daemon may read this new entry and ack it even before kernel can notify userspace about it through kobject_uevent() call. If that happens then we have a potential race between dump_ack_store->kobject_put() and kobject_uevent which can lead to use-after-free of a kernfs object resulting in a kernel crash. This patch fixes this race by protecting the sysfs file creation/notification by holding a reference count on kobject until we safely send kobject_uevent(). The function create_dump_obj() returns the dump object which if used by caller function will end up in use-after-free problem again. However, the return value of create_dump_obj() function isn't being used today and there is no need as well. Hence change it to return void to make this fix complete. Fixes: c7e64b9ce04a ("powerpc/powernv Platform dump interface") Signed-off-by: Vasant Hegde <hegdevasant@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20201017164210.264619-1-hegdevasant@linux.vnet.ibm.com
2020-10-16Merge tag 'powerpc-5.10-1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc updates from Michael Ellerman: - A series from Nick adding ARCH_WANT_IRQS_OFF_ACTIVATE_MM & selecting it for powerpc, as well as a related fix for sparc. - Remove support for PowerPC 601. - Some fixes for watchpoints & addition of a new ptrace flag for detecting ISA v3.1 (Power10) watchpoint features. - A fix for kernels using 4K pages and the hash MMU on bare metal Power9 systems with > 16TB of RAM, or RAM on the 2nd node. - A basic idle driver for shallow stop states on Power10. - Tweaks to our sched domains code to better inform the scheduler about the hardware topology on Power9/10, where two SMT4 cores can be presented by firmware as an SMT8 core. - A series doing further reworks & cleanups of our EEH code. - Addition of a filter for RTAS (firmware) calls done via sys_rtas(), to prevent root from overwriting kernel memory. - Other smaller features, fixes & cleanups. Thanks to: Alexey Kardashevskiy, Andrew Donnellan, Aneesh Kumar K.V, Athira Rajeev, Biwen Li, Cameron Berkenpas, Cédric Le Goater, Christophe Leroy, Christoph Hellwig, Colin Ian King, Daniel Axtens, David Dai, Finn Thain, Frederic Barrat, Gautham R. Shenoy, Greg Kurz, Gustavo Romero, Ira Weiny, Jason Yan, Joel Stanley, Jordan Niethe, Kajol Jain, Konrad Rzeszutek Wilk, Laurent Dufour, Leonardo Bras, Liu Shixin, Luca Ceresoli, Madhavan Srinivasan, Mahesh Salgaonkar, Nathan Lynch, Nicholas Mc Guire, Nicholas Piggin, Nick Desaulniers, Oliver O'Halloran, Pedro Miraglia Franco de Carvalho, Pratik Rajesh Sampat, Qian Cai, Qinglang Miao, Ravi Bangoria, Russell Currey, Satheesh Rajendran, Scott Cheloha, Segher Boessenkool, Srikar Dronamraju, Stan Johnson, Stephen Kitt, Stephen Rothwell, Thiago Jung Bauermann, Tyrel Datwyler, Vaibhav Jain, Vaidyanathan Srinivasan, Vasant Hegde, Wang Wensheng, Wolfram Sang, Yang Yingliang, zhengbin. * tag 'powerpc-5.10-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (228 commits) Revert "powerpc/pci: unmap legacy INTx interrupts when a PHB is removed" selftests/powerpc: Fix eeh-basic.sh exit codes cpufreq: powernv: Fix frame-size-overflow in powernv_cpufreq_reboot_notifier powerpc/time: Make get_tb() common to PPC32 and PPC64 powerpc/time: Make get_tbl() common to PPC32 and PPC64 powerpc/time: Remove get_tbu() powerpc/time: Avoid using get_tbl() and get_tbu() internally powerpc/time: Make mftb() common to PPC32 and PPC64 powerpc/time: Rename mftbl() to mftb() powerpc/32s: Remove #ifdef CONFIG_PPC_BOOK3S_32 in head_book3s_32.S powerpc/32s: Rename head_32.S to head_book3s_32.S powerpc/32s: Setup the early hash table at all time. powerpc/time: Remove ifdef in get_dec() and set_dec() powerpc: Remove get_tb_or_rtc() powerpc: Remove __USE_RTC() powerpc: Tidy up a bit after removal of PowerPC 601. powerpc: Remove support for PowerPC 601 powerpc: Remove PowerPC 601 powerpc: Drop SYNC_601() ISYNC_601() and SYNC() powerpc: Remove CONFIG_PPC601_SYNC_FIX ...
2020-10-16mm/memory_hotplug: prepare passing flags to add_memory() and friendsDavid Hildenbrand
We soon want to pass flags, e.g., to mark added System RAM resources. mergeable. Prepare for that. This patch is based on a similar patch by Oscar Salvador: https://lkml.kernel.org/r/20190625075227.15193-3-osalvador@suse.de Signed-off-by: David Hildenbrand <david@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Juergen Gross <jgross@suse.com> # Xen related part Reviewed-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com> Acked-by: Wei Liu <wei.liu@kernel.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Baoquan He <bhe@redhat.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: Len Brown <lenb@kernel.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: Dave Jiang <dave.jiang@intel.com> Cc: "K. Y. Srinivasan" <kys@microsoft.com> Cc: Haiyang Zhang <haiyangz@microsoft.com> Cc: Stephen Hemminger <sthemmin@microsoft.com> Cc: Wei Liu <wei.liu@kernel.org> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: David Hildenbrand <david@redhat.com> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Jason Wang <jasowang@redhat.com> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Stefano Stabellini <sstabellini@kernel.org> Cc: "Oliver O'Halloran" <oohall@gmail.com> Cc: Pingfan Liu <kernelfans@gmail.com> Cc: Nathan Lynch <nathanl@linux.ibm.com> Cc: Libor Pechacek <lpechacek@suse.cz> Cc: Anton Blanchard <anton@ozlabs.org> Cc: Leonardo Bras <leobras.c@gmail.com> Cc: Ard Biesheuvel <ardb@kernel.org> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Julien Grall <julien@xen.org> Cc: Kees Cook <keescook@chromium.org> Cc: Roger Pau Monné <roger.pau@citrix.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Wei Yang <richardw.yang@linux.intel.com> Link: https://lkml.kernel.org/r/20200911103459.10306-5-david@redhat.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-16powerpc/opal_elog: Handle multiple writes to ack attributeAneesh Kumar K.V
Even though we use self removing sysfs helper, we still need to make sure we do the final kobject delete conditionally. sysfs_remove_file_self() will handle parallel calls to remove the sysfs attribute file and returns true only in the caller that removed the attribute file. The other parallel callers are returned false. Do the final kobject delete checking the return value of sysfs_remove_file_self(). Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Reviewed-by: Mahesh Salgaonkar <mahesh@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20201014064813.109515-1-aneesh.kumar@linux.ibm.com
2020-10-06powerpc/eeh: Clean up PE addressingOliver O'Halloran
When support for EEH on PowerNV was added a lot of pseries specific code was made "generic" and some of the quirks of pseries EEH came along for the ride. One of the stranger quirks is eeh_pe containing two types of PE address: pe->addr and pe->config_addr. There reason for this appears to be historical baggage rather than any real requirements. On pseries EEH PEs are manipulated using RTAS calls. Each EEH RTAS call takes a "PE configuration address" as an input which is used to identify which EEH PE is being manipulated by the call. When initialising the EEH state for a device the first thing we need to do is determine the configuration address for the PE which contains the device so we can enable EEH on that PE. This process is outlined in PAPR which is the modern (i.e post-2003) FW specification for pseries. However, EEH support was first described in the pSeries RISC Platform Architecture (RPA) and although they are mostly compatible EEH is one of the areas where they are not. The major difference is that RPA doesn't actually have the concept of a PE. On RPA systems the EEH RTAS calls are done on a per-device basis using the same config_addr that would be passed to the RTAS functions to access PCI config space (e.g. ibm,read-pci-config). The config_addr is not identical since the function and config register offsets of the config_addr must be set to zero. EEH operations being done on a per-device basis doesn't make a whole lot of sense when you consider how EEH was implemented on legacy PCI systems. For legacy PCI(-X) systems EEH was implemented using special PCI-PCI bridges which contained logic to detect errors and freeze the secondary bus when one occurred. This means that the EEH enabled state is shared among all devices behind that EEH bridge. As a result there's no way to implement the per-device control required for the semantics specified by RPA. It can be made to work if we assume that a separate EEH bridge exists for each EEH capable PCI slot and there are no bridges behind those slots. However, RPA also specifies the ibm,configure-bridge RTAS call for re-initalising bridges behind EEH capable slots after they are reset due to an EEH event so that is probably not a valid assumption. This incoherence was fixed in later PAPR, which succeeded RPA. Unfortunately, since Linux EEH support seems to have been implemented based on the RPA spec some of the legacy assumptions were carried over (probably for POWER4 compatibility). The fix made in PAPR was the introduction of the "PE" concept and redefining the EEH RTAS calls (set-eeh-option, reset-slot, etc) to operate on a per-PE basis so all devices behind an EEH bride would share the same EEH state. The "config_addr" argument to the EEH RTAS calls became the "PE_config_addr" and the OS was required to use the ibm,get-config-addr-info RTAS call to find the correct PE address for the device. When support for the new interfaces was added to Linux it was implemented using something like: At probe time: pdn->eeh_config_addr = rtas_config_addr(pdn); pdn->eeh_pe_config_addr = rtas_get_config_addr_info(pdn); When performing an RTAS call: config_addr = pdn->eeh_config_addr; if (pdn->eeh_pe_config_addr) config_addr = pdn->eeh_pe_config_addr; rtas_call(..., config_addr, ...); In other words, if the ibm,get-config-addr-info RTAS call is implemented and returned a valid result we'd use that as the argument to the EEH RTAS calls. If not, Linux would fall back to using the device's config_addr. Over time these addresses have moved around going from pci_dn to eeh_dev and finally into eeh_pe. Today the users look like this: config_addr = pe->config_addr; if (pe->addr) config_addr = pe->addr; rtas_call(..., config_addr, ...); However, considering the EEH core always operates on a per-PE basis and even on pseries the only per-device operation is the initial call to ibm,set-eeh-option I'm not sure if any of this actually works on an RPA system today. It doesn't make much sense to have the fallback address in a generic structure either since the bulk of the code which reference it is in pseries anyway. The EEH core makes a token effort to support looking up a PE using the config_addr by having two arguments to eeh_pe_get(). However, a survey of all the callers to eeh_pe_get() shows that all bar one have the config_addr argument hard-coded to zero.The only caller that doesn't is in eeh_pe_tree_insert() which has: if (!eeh_has_flag(EEH_VALID_PE_ZERO) && !edev->pe_config_addr) return -EINVAL; pe = eeh_pe_get(hose, edev->pe_config_addr, edev->bdfn); The third argument (config_addr) is only used if the second (pe->addr) argument is invalid. The preceding check ensures that the call to eeh_pe_get() will never happen if edev->pe_config_addr is invalid so there is no situation where eeh_pe_get() will search for a PE based on the 3rd argument. The check also means that we'll never insert a PE into the tree where pe_config_addr is zero since EEH_VALID_PE_ZERO is never set on pseries. All the users of the fallback address on pseries never actually use the fallback and all the only caller that supplies something for the config_addr argument to eeh_pe_get() never use it either. It's all dead code. This patch removes the fallback address from eeh_pe since nothing uses it. Specificly, we do this by: 1) Removing pe->config_addr 2) Removing the EEH_VALID_PE_ZERO flag 3) Removing the fallback address argument to eeh_pe_get(). 4) Removing all the checks for pe->addr being zero in the pseries EEH code. This leaves us with PE's only being identified by what's in their pe->addr field and the EEH core relying on the platform to ensure that eeh_dev's are only inserted into the EEH tree if they're actually inside a PE. No functional changes, I hope. Signed-off-by: Oliver O'Halloran <oohall@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200918093050.37344-9-oohall@gmail.com
2020-10-06powerpc/eeh: Move EEH initialisation to an arch initcallOliver O'Halloran
The initialisation of EEH mostly happens in a core_initcall_sync initcall, followed by registering a bus notifier later on in an arch_initcall. Anything involving initcall dependecies is mostly incomprehensible unless you've spent a while staring at code so here's the full sequence: ppc_md.setup_arch <-- pci_controllers are created here ...time passes... core_initcall <-- pci_dns are created from DT nodes core_initcall_sync <-- platforms call eeh_init() postcore_initcall <-- PCI bus type is registered postcore_initcall_sync arch_initcall <-- EEH pci_bus notifier registered subsys_initcall <-- PHBs are scanned here There's no real requirement to do the EEH setup at the core_initcall_sync level. It just needs to be done after pci_dn's are created and before we start scanning PHBs. Simplify the flow a bit by moving the platform EEH inititalisation to an arch_initcall so we can fold the bus notifier registration into eeh_init(). Signed-off-by: Oliver O'Halloran <oohall@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200918093050.37344-5-oohall@gmail.com
2020-10-06powerpc/powernv: Stop using eeh_ops->init()Oliver O'Halloran
Fold pnv_eeh_init() into eeh_powernv_init() rather than having eeh_init() call it via eeh_ops->init(). It's simpler and it'll let us delete eeh_ops.init. Signed-off-by: Oliver O'Halloran <oohall@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200918093050.37344-2-oohall@gmail.com
2020-10-06powerpc/eeh: Rework EEH initialisationOliver O'Halloran
Drop the EEH register / unregister ops thing and have the platform pass the ops structure into eeh_init() directly. This takes one initcall out of the EEH setup path and it means we're only doing EEH setup on the platforms which actually support it. It's also less code and generally easier to follow. No functional changes. Signed-off-by: Oliver O'Halloran <oohall@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200918093050.37344-1-oohall@gmail.com
2020-10-06powerpc/powernv/elog: Fix race while processing OPAL error log event.Mahesh Salgaonkar
Every error log reported by OPAL is exported to userspace through a sysfs interface and notified using kobject_uevent(). The userspace daemon (opal_errd) then reads the error log and acknowledges the error log is saved safely to disk. Once acknowledged the kernel removes the respective sysfs file entry causing respective resources to be released including kobject. However it's possible the userspace daemon may already be scanning elog entries when a new sysfs elog entry is created by the kernel. User daemon may read this new entry and ack it even before kernel can notify userspace about it through kobject_uevent() call. If that happens then we have a potential race between elog_ack_store->kobject_put() and kobject_uevent which can lead to use-after-free of a kernfs object resulting in a kernel crash. eg: BUG: Unable to handle kernel data access on read at 0x6b6b6b6b6b6b6bfb Faulting instruction address: 0xc0000000008ff2a0 Oops: Kernel access of bad area, sig: 11 [#1] LE PAGE_SIZE=64K MMU=Hash SMP NR_CPUS=2048 NUMA PowerNV CPU: 27 PID: 805 Comm: irq/29-opal-elo Not tainted 5.9.0-rc2-gcc-8.2.0-00214-g6f56a67bcbb5-dirty #363 ... NIP kobject_uevent_env+0xa0/0x910 LR elog_event+0x1f4/0x2d0 Call Trace: 0x5deadbeef0000122 (unreliable) elog_event+0x1f4/0x2d0 irq_thread_fn+0x4c/0xc0 irq_thread+0x1c0/0x2b0 kthread+0x1c4/0x1d0 ret_from_kernel_thread+0x5c/0x6c This patch fixes this race by protecting the sysfs file creation/notification by holding a reference count on kobject until we safely send kobject_uevent(). The function create_elog_obj() returns the elog object which if used by caller function will end up in use-after-free problem again. However, the return value of create_elog_obj() function isn't being used today and there is no need as well. Hence change it to return void to make this fix complete. Fixes: 774fea1a38c6 ("powerpc/powernv: Read OPAL error log and export it through sysfs") Cc: stable@vger.kernel.org # v3.15+ Reported-by: Oliver O'Halloran <oohall@gmail.com> Signed-off-by: Mahesh Salgaonkar <mahesh@linux.ibm.com> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Reviewed-by: Oliver O'Halloran <oohall@gmail.com> Reviewed-by: Vasant Hegde <hegdevasant@linux.vnet.ibm.com> [mpe: Rework the logic to use a single return, reword comments, add oops] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20201006122051.190176-1-mpe@ellerman.id.au
2020-09-18powerpc/powernv: fix wrong warning message in opalcore_config_init()Qinglang Miao
The logic of the warn output is incorrect. The two args should be exchanged. Signed-off-by: Qinglang Miao <miaoqinglang@huawei.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200916062129.190864-1-miaoqinglang@huawei.com
2020-09-18powerpc/smp: Move ppc_md.cpu_die() to smp_ops.cpu_offline_self()Michael Ellerman
We have smp_ops->cpu_die() and ppc_md.cpu_die(). One of them offlines the current CPU and one offlines another CPU, can you guess which is which? Also one is in smp_ops and one is in ppc_md? So rename ppc_md.cpu_die(), to cpu_offline_self(), because that's what it does. And move it into smp_ops where it belongs. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200819015634.1974478-3-mpe@ellerman.id.au
2020-09-15powerpc/powernv/idle: add a basic stop 0-3 driver for POWER10Nicholas Piggin
This driver does not restore stop > 3 state, so it limits itself to states which do not lose full state or TB. The POWER10 SPRs are sufficiently different from P9 that it seems easier to split out the P10 code. The POWER10 deep sleep code (e.g., the BHRB restore) has been taken out, but it can be re-added when stop > 3 support is added. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Tested-by: Pratik Rajesh Sampat<psampat@linux.ibm.com> Tested-by: Vaidyanathan Srinivasan <svaidy@linux.ibm.com> Reviewed-by: Pratik Rajesh Sampat<psampat@linux.ibm.com> Reviewed-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200819094700.493399-1-npiggin@gmail.com
2020-09-14Merge branch 'fixes' into nextMichael Ellerman
Bring in our fixes branch for this cycle which avoids some small conflicts with upcoming commits.
2020-09-08powerpc/powernv: Print helpful message when cores guardedJoel Stanley
Often the firmware will guard out cores after a crash. This often undesirable, and is not immediately noticeable. This adds an informative message when a CPU device tree nodes are marked bad in the device tree. Signed-off-by: Joel Stanley <joel@jms.id.au> [mpe: Use an eye-catcher that's less likely to get us in trouble] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190801051630.5804-1-joel@jms.id.au
2020-08-27Revert "powerpc/powernv/idle: Replace CPU feature check with PVR check"Pratik Rajesh Sampat
cpuidle stop state implementation has minor optimizations for P10 where hardware preserves more SPR registers compared to P9. The current P9 driver works for P10, although does few extra save-restores. P9 driver can provide the required power management features like SMT thread folding and core level power savings on a P10 platform. Until the P10 stop driver is available, revert the commit which allows for only P9 systems to utilize cpuidle and blocks all idle stop states for P10. CPU idle states are enabled and tested on the P10 platform with this fix. This reverts commit 8747bf36f312356f8a295a0c39ff092d65ce75ae. Fixes: 8747bf36f312 ("powerpc/powernv/idle: Replace CPU feature check with PVR check") Signed-off-by: Pratik Rajesh Sampat <psampat@linux.ibm.com> Reviewed-by: Vaidyanathan Srinivasan <svaidy@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200826082918.89306-1-psampat@linux.ibm.com
2020-08-25powerpc/powernv: Fix spurious kerneldoc warnings in opal-prd.cOliver O'Halloran
Comments opening with /** are parsed by kerneldoc and this causes the following warning to be printed: arch/powerpc/platforms/powernv/opal-prd.c:31: warning: cannot understand function prototype: 'struct opal_prd_msg_queue_item ' opal_prd_mesg_queue_item is an internal data structure so there's no real need for it to be documented at all. Fix up the comment to squash the warning. Signed-off-by: Oliver O'Halloran <oohall@gmail.com> Reviewed-by: Joel Stanley <joel@jms.id.au> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200804005410.146094-5-oohall@gmail.com
generated by cgit-pink 1.4.1 (git 2.36.1) at 2024-09-25 18:14:04 +0000