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2023-04-27Merge tag 'modules-6.4-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux Pull module updates from Luis Chamberlain: "The summary of the changes for this pull requests is: - Song Liu's new struct module_memory replacement - Nick Alcock's MODULE_LICENSE() removal for non-modules - My cleanups and enhancements to reduce the areas where we vmalloc module memory for duplicates, and the respective debug code which proves the remaining vmalloc pressure comes from userspace. Most of the changes have been in linux-next for quite some time except the minor fixes I made to check if a module was already loaded prior to allocating the final module memory with vmalloc and the respective debug code it introduces to help clarify the issue. Although the functional change is small it is rather safe as it can only *help* reduce vmalloc space for duplicates and is confirmed to fix a bootup issue with over 400 CPUs with KASAN enabled. I don't expect stable kernels to pick up that fix as the cleanups would have also had to have been picked up. Folks on larger CPU systems with modules will want to just upgrade if vmalloc space has been an issue on bootup. Given the size of this request, here's some more elaborate details: The functional change change in this pull request is the very first patch from Song Liu which replaces the 'struct module_layout' with a new 'struct module_memory'. The old data structure tried to put together all types of supported module memory types in one data structure, the new one abstracts the differences in memory types in a module to allow each one to provide their own set of details. This paves the way in the future so we can deal with them in a cleaner way. If you look at changes they also provide a nice cleanup of how we handle these different memory areas in a module. This change has been in linux-next since before the merge window opened for v6.3 so to provide more than a full kernel cycle of testing. It's a good thing as quite a bit of fixes have been found for it. Jason Baron then made dynamic debug a first class citizen module user by using module notifier callbacks to allocate / remove module specific dynamic debug information. Nick Alcock has done quite a bit of work cross-tree to remove module license tags from things which cannot possibly be module at my request so to: a) help him with his longer term tooling goals which require a deterministic evaluation if a piece a symbol code could ever be part of a module or not. But quite recently it is has been made clear that tooling is not the only one that would benefit. Disambiguating symbols also helps efforts such as live patching, kprobes and BPF, but for other reasons and R&D on this area is active with no clear solution in sight. b) help us inch closer to the now generally accepted long term goal of automating all the MODULE_LICENSE() tags from SPDX license tags In so far as a) is concerned, although module license tags are a no-op for non-modules, tools which would want create a mapping of possible modules can only rely on the module license tag after the commit 8b41fc4454e ("kbuild: create modules.builtin without Makefile.modbuiltin or tristate.conf"). Nick has been working on this *for years* and AFAICT I was the only one to suggest two alternatives to this approach for tooling. The complexity in one of my suggested approaches lies in that we'd need a possible-obj-m and a could-be-module which would check if the object being built is part of any kconfig build which could ever lead to it being part of a module, and if so define a new define -DPOSSIBLE_MODULE [0]. A more obvious yet theoretical approach I've suggested would be to have a tristate in kconfig imply the same new -DPOSSIBLE_MODULE as well but that means getting kconfig symbol names mapping to modules always, and I don't think that's the case today. I am not aware of Nick or anyone exploring either of these options. Quite recently Josh Poimboeuf has pointed out that live patching, kprobes and BPF would benefit from resolving some part of the disambiguation as well but for other reasons. The function granularity KASLR (fgkaslr) patches were mentioned but Joe Lawrence has clarified this effort has been dropped with no clear solution in sight [1]. In the meantime removing module license tags from code which could never be modules is welcomed for both objectives mentioned above. Some developers have also welcomed these changes as it has helped clarify when a module was never possible and they forgot to clean this up, and so you'll see quite a bit of Nick's patches in other pull requests for this merge window. I just picked up the stragglers after rc3. LWN has good coverage on the motivation behind this work [2] and the typical cross-tree issues he ran into along the way. The only concrete blocker issue he ran into was that we should not remove the MODULE_LICENSE() tags from files which have no SPDX tags yet, even if they can never be modules. Nick ended up giving up on his efforts due to having to do this vetting and backlash he ran into from folks who really did *not understand* the core of the issue nor were providing any alternative / guidance. I've gone through his changes and dropped the patches which dropped the module license tags where an SPDX license tag was missing, it only consisted of 11 drivers. To see if a pull request deals with a file which lacks SPDX tags you can just use: ./scripts/spdxcheck.py -f \ $(git diff --name-only commid-id | xargs echo) You'll see a core module file in this pull request for the above, but that's not related to his changes. WE just need to add the SPDX license tag for the kernel/module/kmod.c file in the future but it demonstrates the effectiveness of the script. Most of Nick's changes were spread out through different trees, and I just picked up the slack after rc3 for the last kernel was out. Those changes have been in linux-next for over two weeks. The cleanups, debug code I added and final fix I added for modules were motivated by David Hildenbrand's report of boot failing on a systems with over 400 CPUs when KASAN was enabled due to running out of virtual memory space. Although the functional change only consists of 3 lines in the patch "module: avoid allocation if module is already present and ready", proving that this was the best we can do on the modules side took quite a bit of effort and new debug code. The initial cleanups I did on the modules side of things has been in linux-next since around rc3 of the last kernel, the actual final fix for and debug code however have only been in linux-next for about a week or so but I think it is worth getting that code in for this merge window as it does help fix / prove / evaluate the issues reported with larger number of CPUs. Userspace is not yet fixed as it is taking a bit of time for folks to understand the crux of the issue and find a proper resolution. Worst come to worst, I have a kludge-of-concept [3] of how to make kernel_read*() calls for modules unique / converge them, but I'm currently inclined to just see if userspace can fix this instead" Link: https://lore.kernel.org/all/Y/kXDqW+7d71C4wz@bombadil.infradead.org/ [0] Link: https://lkml.kernel.org/r/025f2151-ce7c-5630-9b90-98742c97ac65@redhat.com [1] Link: https://lwn.net/Articles/927569/ [2] Link: https://lkml.kernel.org/r/20230414052840.1994456-3-mcgrof@kernel.org [3] * tag 'modules-6.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux: (121 commits) module: add debugging auto-load duplicate module support module: stats: fix invalid_mod_bytes typo module: remove use of uninitialized variable len module: fix building stats for 32-bit targets module: stats: include uapi/linux/module.h module: avoid allocation if module is already present and ready module: add debug stats to help identify memory pressure module: extract patient module check into helper modules/kmod: replace implementation with a semaphore Change DEFINE_SEMAPHORE() to take a number argument module: fix kmemleak annotations for non init ELF sections module: Ignore L0 and rename is_arm_mapping_symbol() module: Move is_arm_mapping_symbol() to module_symbol.h module: Sync code of is_arm_mapping_symbol() scripts/gdb: use mem instead of core_layout to get the module address interconnect: remove module-related code interconnect: remove MODULE_LICENSE in non-modules zswap: remove MODULE_LICENSE in non-modules zpool: remove MODULE_LICENSE in non-modules x86/mm/dump_pagetables: remove MODULE_LICENSE in non-modules ...
2023-04-27Merge tag 'driver-core-6.4-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core Pull driver core updates from Greg KH: "Here is the large set of driver core changes for 6.4-rc1. Once again, a busy development cycle, with lots of changes happening in the driver core in the quest to be able to move "struct bus" and "struct class" into read-only memory, a task now complete with these changes. This will make the future rust interactions with the driver core more "provably correct" as well as providing more obvious lifetime rules for all busses and classes in the kernel. The changes required for this did touch many individual classes and busses as many callbacks were changed to take const * parameters instead. All of these changes have been submitted to the various subsystem maintainers, giving them plenty of time to review, and most of them actually did so. Other than those changes, included in here are a small set of other things: - kobject logging improvements - cacheinfo improvements and updates - obligatory fw_devlink updates and fixes - documentation updates - device property cleanups and const * changes - firwmare loader dependency fixes. All of these have been in linux-next for a while with no reported problems" * tag 'driver-core-6.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (120 commits) device property: make device_property functions take const device * driver core: update comments in device_rename() driver core: Don't require dynamic_debug for initcall_debug probe timing firmware_loader: rework crypto dependencies firmware_loader: Strip off \n from customized path zram: fix up permission for the hot_add sysfs file cacheinfo: Add use_arch[|_cache]_info field/function arch_topology: Remove early cacheinfo error message if -ENOENT cacheinfo: Check cache properties are present in DT cacheinfo: Check sib_leaf in cache_leaves_are_shared() cacheinfo: Allow early level detection when DT/ACPI info is missing/broken cacheinfo: Add arm64 early level initializer implementation cacheinfo: Add arch specific early level initializer tty: make tty_class a static const structure driver core: class: remove struct class_interface * from callbacks driver core: class: mark the struct class in struct class_interface constant driver core: class: make class_register() take a const * driver core: class: mark class_release() as taking a const * driver core: remove incorrect comment for device_create* MIPS: vpe-cmp: remove module owner pointer from struct class usage. ...
2023-04-27Merge tag 'pci-v6.4-changes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/pci/pci Pull pci updates from Bjorn Helgaas: "Resource management: - Add pci_dev_for_each_resource() and pci_bus_for_each_resource() iterators PCIe native device hotplug: - Fix AB-BA deadlock between reset_lock and device_lock Power management: - Wait longer for devices to become ready after resume (as we do for reset) to accommodate Intel Titan Ridge xHCI devices - Extend D3hot delay for NVIDIA HDA controllers to avoid unrecoverable devices after a bus reset Error handling: - Clear PCIe Device Status after EDR since generic error recovery now only clears it when AER is native ASPM: - Work around Chromebook firmware defect that clobbers Capability list (including ASPM L1 PM Substates Cap) when returning from D3cold to D0 Freescale i.MX6 PCIe controller driver: - Install imprecise external abort handler only when DT indicates PCIe support Freescale Layerscape PCIe controller driver: - Add ls1028a endpoint mode support Qualcomm PCIe controller driver: - Add SM8550 DT binding and driver support - Add SDX55 DT binding and driver support - Use bulk APIs for clocks of IP 1.0.0, 2.3.2, 2.3.3 - Use bulk APIs for reset of IP 2.1.0, 2.3.3, 2.4.0 - Add DT "mhi" register region for supported SoCs - Expose link transition counts via debugfs to help debug low power issues - Support system suspend and resume; reduce interconnect bandwidth and turn off clock and PHY if there are no active devices - Enable async probe by default to reduce boot time Miscellaneous: - Sort controller Kconfig entries by vendor" * tag 'pci-v6.4-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/pci/pci: (56 commits) PCI: xilinx: Drop obsolete dependency on COMPILE_TEST PCI: mobiveil: Sort Kconfig entries by vendor PCI: dwc: Sort Kconfig entries by vendor PCI: Sort controller Kconfig entries by vendor PCI: Use consistent controller Kconfig menu entry language PCI: xilinx-nwl: Add 'Xilinx' to Kconfig prompt PCI: hv: Add 'Microsoft' to Kconfig prompt PCI: meson: Add 'Amlogic' to Kconfig prompt PCI: Use of_property_present() for testing DT property presence PCI/PM: Extend D3hot delay for NVIDIA HDA controllers dt-bindings: PCI: qcom: Document msi-map and msi-map-mask properties PCI: qcom: Add SM8550 PCIe support dt-bindings: PCI: qcom: Add SM8550 compatible PCI: qcom: Add support for SDX55 SoC dt-bindings: PCI: qcom-ep: Fix the unit address used in example dt-bindings: PCI: qcom: Add SDX55 SoC dt-bindings: PCI: qcom: Update maintainers entry PCI: qcom: Enable async probe by default PCI: qcom: Add support for system suspend and resume PCI/PM: Drop pci_bridge_wait_for_secondary_bus() timeout parameter ...
2023-04-26powerpc: Fix merge conflict between pcrel and copy_thread changesNicholas Piggin
Fix a conflict between commit 4e991e3c16a35 ("powerpc: add CFUNC assembly label annotation") and commit b504b6aade040 ("powerpc: differentiate kthread from user kernel thread start"). Fixes: 4e991e3c16a35 ("powerpc: add CFUNC assembly label annotation") Fixes: b504b6aade040 ("powerpc: differentiate kthread from user kernel thread start") Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20230426055848.402993-2-npiggin@gmail.com
2023-04-25Merge tag 'timers-core-2023-04-24' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull timers and timekeeping updates from Thomas Gleixner: - Improve the VDSO build time checks to cover all dynamic relocations VDSO does not allow dynamic relocations, but the build time check is incomplete and fragile. It's based on architectures specifying the relocation types to search for and does not handle R_*_NONE relocation entries correctly. R_*_NONE relocations are injected by some GNU ld variants if they fail to determine the exact .rel[a]/dyn_size to cover trailing zeros. R_*_NONE relocations must be ignored by dynamic loaders, so they should be ignored in the build time check too. Remove the architecture specific relocation types to check for and validate strictly that no other relocations than R_*_NONE end up in the VSDO .so file. - Prefer signal delivery to the current thread for CLOCK_PROCESS_CPUTIME_ID based posix-timers Such timers prefer to deliver the signal to the main thread of a process even if the context in which the timer expires is the current task. This has the downside that it might wake up an idle thread. As there is no requirement or guarantee that the signal has to be delivered to the main thread, avoid this by preferring the current task if it is part of the thread group which shares sighand. This not only avoids waking idle threads, it also distributes the signal delivery in case of multiple timers firing in the context of different threads close to each other better. - Align the tick period properly (again) For a long time the tick was starting at CLOCK_MONOTONIC zero, which allowed users space applications to either align with the tick or to place a periodic computation so that it does not interfere with the tick. The alignement of the tick period was more by chance than by intention as the tick is set up before a high resolution clocksource is installed, i.e. timekeeping is still tick based and the tick period advances from there. The early enablement of sched_clock() broke this alignement as the time accumulated by sched_clock() is taken into account when timekeeping is initialized. So the base value now(CLOCK_MONOTONIC) is not longer a multiple of tick periods, which breaks applications which relied on that behaviour. Cure this by aligning the tick starting point to the next multiple of tick periods, i.e 1000ms/CONFIG_HZ. - A set of NOHZ fixes and enhancements: * Cure the concurrent writer race for idle and IO sleeptime statistics The statitic values which are exposed via /proc/stat are updated from the CPU local idle exit and remotely by cpufreq, but that happens without any form of serialization. As a consequence sleeptimes can be accounted twice or worse. Prevent this by restricting the accumulation writeback to the CPU local idle exit and let the remote access compute the accumulated value. * Protect idle/iowait sleep time with a sequence count Reading idle/iowait sleep time, e.g. from /proc/stat, can race with idle exit updates. As a consequence the readout may result in random and potentially going backwards values. Protect this by a sequence count, which fixes the idle time statistics issue, but cannot fix the iowait time problem because iowait time accounting races with remote wake ups decrementing the remote runqueues nr_iowait counter. The latter is impossible to fix, so the only way to deal with that is to document it properly and to remove the assertion in the selftest which triggers occasionally due to that. * Restructure struct tick_sched for better cache layout * Some small cleanups and a better cache layout for struct tick_sched - Implement the missing timer_wait_running() callback for POSIX CPU timers For unknown reason the introduction of the timer_wait_running() callback missed to fixup posix CPU timers, which went unnoticed for almost four years. While initially only targeted to prevent livelocks between a timer deletion and the timer expiry function on PREEMPT_RT enabled kernels, it turned out that fixing this for mainline is not as trivial as just implementing a stub similar to the hrtimer/timer callbacks. The reason is that for CONFIG_POSIX_CPU_TIMERS_TASK_WORK enabled systems there is a livelock issue independent of RT. CONFIG_POSIX_CPU_TIMERS_TASK_WORK=y moves the expiry of POSIX CPU timers out from hard interrupt context to task work, which is handled before returning to user space or to a VM. The expiry mechanism moves the expired timers to a stack local list head with sighand lock held. Once sighand is dropped the task can be preempted and a task which wants to delete a timer will spin-wait until the expiry task is scheduled back in. In the worst case this will end up in a livelock when the preempting task and the expiry task are pinned on the same CPU. The timer wheel has a timer_wait_running() mechanism for RT, which uses a per CPU timer-base expiry lock which is held by the expiry code and the task waiting for the timer function to complete blocks on that lock. This does not work in the same way for posix CPU timers as there is no timer base and expiry for process wide timers can run on any task belonging to that process, but the concept of waiting on an expiry lock can be used too in a slightly different way. Add a per task mutex to struct posix_cputimers_work, let the expiry task hold it accross the expiry function and let the deleting task which waits for the expiry to complete block on the mutex. In the non-contended case this results in an extra mutex_lock()/unlock() pair on both sides. This avoids spin-waiting on a task which is scheduled out, prevents the livelock and cures the problem for RT and !RT systems * tag 'timers-core-2023-04-24' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: posix-cpu-timers: Implement the missing timer_wait_running callback selftests/proc: Assert clock_gettime(CLOCK_BOOTTIME) VS /proc/uptime monotonicity selftests/proc: Remove idle time monotonicity assertions MAINTAINERS: Remove stale email address timers/nohz: Remove middle-function __tick_nohz_idle_stop_tick() timers/nohz: Add a comment about broken iowait counter update race timers/nohz: Protect idle/iowait sleep time under seqcount timers/nohz: Only ever update sleeptime from idle exit timers/nohz: Restructure and reshuffle struct tick_sched tick/common: Align tick period with the HZ tick. selftests/timers/posix_timers: Test delivery of signals across threads posix-timers: Prefer delivery of signals to the current thread vdso: Improve cmd_vdso_check to check all dynamic relocations
2023-04-20powerpc/64: Don't call trace_hardirqs_on() in prep_irq_for_idle()Michael Ellerman
Since commit a01353cf1896 ("cpuidle: Fix ct_idle_*() usage"), the cpuidle entry code calls trace_hardirqs_on() (actually trace_hardirqs_on_prepare()) in ct_cpuidle_enter() before calling into the cpuidle driver. Suggested-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20230406144535.3786008-2-mpe@ellerman.id.au
2023-04-20powerpc/64: Mark prep_irq_for_idle() __cpuidleMichael Ellerman
Code in the idle path is not allowed to be instrumented because RCU is disabled, see commit 0e985e9d2286 ("cpuidle: Add comments about noinstr/__cpuidle usage"). Mark prep_irq_for_idle() __cpuidle, which is equivalent to noinstr, to enforce that. Suggested-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20230406144535.3786008-1-mpe@ellerman.id.au
2023-04-20powerpc/irq: Mark check_return_regs_valid() notraceMichael Ellerman
check_return_regs_valid() is called from the middle of the irq exit handling, which is all notrace, so mark it notrace also. Reported-by: Sachin Sant <sachinp@linux.ibm.com> Link: https://lore.kernel.org/all/4C073F6A-C812-4C4A-BB7A-ECD10B75FB88@linux.ibm.com/ Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20230406122118.3760344-1-mpe@ellerman.id.au
2023-04-20powerpc/64: modules support building with PCREL addresingNicholas Piggin
Build modules using PCREL addressing when CONFIG_PPC_KERNEL_PCREL=y. - The module loader must handle several new relocation types: * R_PPC64_REL24_NOTOC is a function call handled like R_PPC_REL24, but does not restore r2 upon return. The external function call stub is changed to use pcrel addressing to load the function pointer rather than based on the module TOC. * R_PPC64_GOT_PCREL34 is a reference to external data. A GOT table must be built by hand, because the linker adds this during the final link (which is not done for kernel modules). The GOT table is built similarly to the way the external function call stub table is. This section is called .mygot because .got has a special meaning for the linker and can become upset. * R_PPC64_PCREL34 is used for local data addressing, but there is a special case where the percpu section is moved at load-time to the percpu area which is out of range of this relocation. This requires the PCREL34 relocations are converted to use GOT_PCREL34 addressing. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> [mpe: Some coding style & formatting fixups] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20230408021752.862660-7-npiggin@gmail.com
2023-04-20powerpc/64: vmlinux support building with PCREL addresingNicholas Piggin
PC-Relative or PCREL addressing is an extension to the ELF ABI which uses Power ISA v3.1 PC-relative instructions to calculate addresses, rather than the traditional TOC scheme. Add an option to build vmlinux using pcrel addressing. Modules continue to use TOC addressing. - TOC address helpers and r2 are poisoned with -1 when running vmlinux. r2 could be used for something useful once things are ironed out. - Assembly must call C functions with @notoc annotation, or the linker complains aobut a missing nop after the call. This is done with the CFUNC macro introduced earlier. - Boot: with the exception of prom_init, the execution branches to the kernel virtual address early in boot, before any addresses are generated, which ensures 34-bit pcrel addressing does not miss the high PAGE_OFFSET bits. TOC relative addressing has a similar requirement. prom_init does not go to the virtual address and its addresses should not carry over to the post-prom kernel. - Ftrace trampolines are converted from TOC addressing to pcrel addressing, including module ftrace trampolines that currently use the kernel TOC to find ftrace target functions. - BPF function prologue and function calling generation are converted from TOC to pcrel. - copypage_64.S has an interesting problem, prefixed instructions have alignment restrictions so the linker can add padding, which makes the assembler treat the difference between two local labels as non-constant even if alignment is arranged so padding is not required. This may need toolchain help to solve nicely, for now move the prefix instruction out of the alternate patch section to work around it. This reduces kernel text size by about 6%. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20230408021752.862660-6-npiggin@gmail.com
2023-04-20powerpc: add CFUNC assembly label annotationNicholas Piggin
This macro is to be used in assembly where C functions are called. pcrel addressing mode requires branches to functions with a localentry value of 1 to have either a trailing nop or @notoc. This macro permits the latter without changing callers. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> [mpe: Add dummy definitions to fix selftests build] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20230408021752.862660-5-npiggin@gmail.com
2023-04-20powerpc/64: Add support to build with prefixed instructionsNicholas Piggin
Add an option to build kernel and module with prefixed instructions if the CPU and toolchain support it. This is not related to kernel support for userspace execution of prefixed instructions. Building with prefixed instructions breaks some extended inline asm memory addressing, for example it will provide immediates that exceed the range of simple load/store displacement. Whether this is a toolchain or a kernel asm problem remains to be seen. For now, these are replaced with simpler and less efficient direct register addressing when compiling with prefixed. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20230408021752.862660-4-npiggin@gmail.com
2023-04-20powerpc/64s: Run at the kernel virtual address earlier in bootNicholas Piggin
This mostly consolidates the Book3E and Book3S behaviour in boot WRT executing from the physical or virtual address. Book3E sets up kernel virtual linear map in start_initialization_book3e and runs from the virtual linear alias after that. This change makes Book3S begin to execute from the virtual alias at the same point. Book3S can not use its MMU for that at this point, but when the MMU is disabled, the virtual linear address correctly aliases to physical memory because the top bits of the address are ignored with MMU disabled. Secondaries execute from the virtual address similarly early. This reduces the differences between subarchs, but the main motivation was to enable the PC-relative addressing ABI for Book3S, where pointer calculations must execute from the virtual address or the top bits of the pointer will be lost. This is similar to the requirement the TOC relative addressing already has that the TOC pointer use its virtual address. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20230408021752.862660-3-npiggin@gmail.com
2023-04-20powerpc/64: Move initial base and TOC pointer calculationNicholas Piggin
A later change moves the non-prom case to run at the virtual address earlier, which calls for virtual TOC and kernel base. Split these two calculations for prom and non-prom to make that change simpler. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> [mpe: Retain relative_toc call for start_initialization_book3e] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20230408021752.862660-2-npiggin@gmail.com
2023-04-14cpu: Mark panic_smp_self_stop() __noreturnJosh Poimboeuf
In preparation for improving objtool's handling of weak noreturn functions, mark panic_smp_self_stop() __noreturn. Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/r/92d76ab5c8bf660f04fdcd3da1084519212de248.1681342859.git.jpoimboe@kernel.org
2023-04-11powerpc/32: Include thread_info.h in head_booke.hNathan Chancellor
When building with W=1 after commit 80b6093b55e3 ("kbuild: add -Wundef to KBUILD_CPPFLAGS for W=1 builds"), the following warning occurs. In file included from arch/powerpc/kvm/bookehv_interrupts.S:26: arch/powerpc/kvm/../kernel/head_booke.h:20:6: warning: "THREAD_SHIFT" is not defined, evaluates to 0 [-Wundef] 20 | #if (THREAD_SHIFT < 15) | ^~~~~~~~~~~~ THREAD_SHIFT is defined in thread_info.h but it is not directly included in head_booke.h, so it is possible for THREAD_SHIFT to be undefined. Add the include to ensure that THREAD_SHIFT is always defined. Reported-by: kernel test robot <lkp@intel.com> Link: https://lore.kernel.org/202304050954.yskLdczH-lkp@intel.com/ Signed-off-by: Nathan Chancellor <nathan@kernel.org> Reviewed-by: Masahiro Yamada <masahiroy@kernel.org> Reviewed-by: Nick Desaulniers <ndesaulniers@google.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20230406-wundef-thread_shift_booke-v1-1-8deffa4d84f9@kernel.org
2023-04-11powerpc: copy_thread don't set PPR in user interrupt frame regsNicholas Piggin
syscalls do not set the PPR field in their interrupt frame and return from syscall always sets the default PPR for userspace, so setting the value in the ret_from_fork frame is not necessary and mildly inconsistent. Remove it. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20230325122904.2375060-9-npiggin@gmail.com
2023-04-11powerpc: copy_thread don't set _TIF_RESTOREALLNicholas Piggin
In the kernel user thread path, don't set _TIF_RESTOREALL because the thread is required to call kernel_execve() before it returns, which will set _TIF_RESTOREALL if necessary via start_thread(). Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20230325122904.2375060-8-npiggin@gmail.com
2023-04-11powerpc: differentiate kthread from user kernel thread startNicholas Piggin
Kernel created user threads start similarly to kernel threads in that they call a kernel function after first returning from _switch, so they share ret_from_kernel_thread for this. Kernel threads never return from that function though, whereas user threads often do (although some don't, e.g., IO threads). Split these startup functions in two, and catch kernel threads that improperly return from their function. This is intended to make the complicated code a little bit easier to understand. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20230325122904.2375060-7-npiggin@gmail.com
2023-04-11powerpc: copy_thread differentiate kthreads and user mode threadsNicholas Piggin
When copy_thread is given a kernel function to run in arg->fn, this does not necessarily mean it is a kernel thread. User threads can be created this way (e.g., kernel_init, see also x86's copy_thread()). These threads run a kernel function which may call kernel_execve() and return, which returns like a userspace exec(2) syscall. Kernel threads are to be differentiated with PF_KTHREAD, will always have arg->fn set, and should never return from that function, instead calling kthread_exit() to exit. Create separate paths for the kthread and user kernel thread creation logic. The kthread path will never exit and does not require a user interrupt frame, so it gets a minimal stack frame. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20230325122904.2375060-6-npiggin@gmail.com
2023-04-11powerpc/64: ret_from_fork avoid restoring regs twiceNicholas Piggin
If the system call return path always restores NVGPRs then there is no need for ret_from_fork to do it. The HANDLER_RESTORE_NVGPRS does the right thing for this. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20230325122904.2375060-5-npiggin@gmail.com
2023-04-11powerpc: use switch frame for ret_from_kernel_thread parametersNicholas Piggin
The kernel thread path in copy_thread creates a user interrupt frame on stack and stores the function and arg parameters there, and ret_from_kernel_thread loads them. This is a slightly confusing way to overload that frame. Non-volatile registers are loaded from the switch frame, so the parameters can be stored there. The user interrupt frame is now only used by user threads when they return to user. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20230325122904.2375060-4-npiggin@gmail.com
2023-04-11powerpc: copy_thread make ret_from_fork register setup consistentNicholas Piggin
The ret_from_fork code for 64e and 32-bit set r3 for syscall_exit_prepare the same way that 64s does, so there should be no need to special-case them in copy_thread. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20230325122904.2375060-3-npiggin@gmail.com
2023-04-11powerpc: copy_thread remove unused pkey codeNicholas Piggin
The pkey registers (AMR, IAMR) do not get loaded from the switch frame so it is pointless to save anything there. Remove the dead code. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20230325122904.2375060-2-npiggin@gmail.com
2023-04-04PCI: Introduce pci_dev_for_each_resource()Mika Westerberg
Instead of open-coding it everywhere introduce a tiny helper that can be used to iterate over each resource of a PCI device, and convert the most obvious users into it. While at it drop doubled empty line before pdev_sort_resources(). No functional changes intended. Suggested-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20230330162434.35055-4-andriy.shevchenko@linux.intel.com Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Krzysztof Wilczyński <kw@linux.com>
2023-04-04powerpc/isa-bridge: Remove open coded "ranges" parsingRob Herring
"ranges" is a standard property with common parsing functions. Users shouldn't be implementing their own parsing of it. Reimplement the ISA brige "ranges" parsing using the common ranges iterator functions. The common routines are flexible enough to work on PCI and non-PCI to ISA bridges, so refactor pci_process_ISA_OF_ranges() and isa_bridge_init_non_pci() into a single implementation. Signed-off-by: Rob Herring <robh@kernel.org> [mpe: Unsplit some strings and use pr_xxx()] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20230327223045.819852-1-robh@kernel.org
2023-04-03Merge 6.3-rc5 into driver-core-nextGreg Kroah-Hartman
We need the fixes in here for testing, as well as the driver core changes for documentation updates to build on. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-04-02Merge tag 'powerpc-6.3-4' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc fixes from Michael Ellerman: - Fix a false positive warning in __pte_needs_flush() (with DEBUG_VM=y) - Fix oops when a PF_IO_WORKER thread tries to core dump - Don't try to reconfigure VAS when it's disabled Thanks to Benjamin Gray, Haren Myneni, Jens Axboe, Nathan Lynch, and Russell Currey. * tag 'powerpc-6.3-4' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: powerpc/pseries/vas: Ignore VAS update for DLPAR if copy/paste is not enabled powerpc: Don't try to copy PPR for task with NULL pt_regs powerpc/64s: Fix __pte_needs_flush() false positive warning
2023-03-30powerpc: Use of_property_read_bool() for boolean propertiesRob Herring
It is preferred to use typed property access functions (i.e. of_property_read_<type> functions) rather than low-level of_get_property/of_find_property functions for reading properties. Convert reading boolean properties to of_property_read_bool(). Signed-off-by: Rob Herring <robh@kernel.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20230310144659.1541127-1-robh@kernel.org
2023-03-30powerpc: Use of_property_present() for testing DT property presenceRob Herring
It is preferred to use typed property access functions (i.e. of_property_read_<type> functions) rather than low-level of_get_property/of_find_property functions for reading properties. As part of this, convert of_get_property/of_find_property calls to the recently added of_property_present() helper when we just want to test for presence of a property and nothing more. Signed-off-by: Rob Herring <robh@kernel.org> [mpe: Drop change in ppc4xx_probe_pci_bridge(), formatting] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20230310144657.1541039-1-robh@kernel.org
2023-03-30powerpc/rtas: lockdep annotationsNathan Lynch
Add lockdep annotations for the following properties that must hold: * Any error log retrieval must be atomically coupled with the prior RTAS call, without a window for another RTAS call to occur before the error log can be retrieved. * All users of the core rtas_args parameter block must hold rtas_lock. Move the definitions of rtas_lock and rtas_args up in the file so that __do_enter_rtas_trace() can refer to them. Signed-off-by: Nathan Lynch <nathanl@linux.ibm.com> Reviewed-by: Andrew Donnellan <ajd@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20230220-rtas-queue-for-6-4-v1-6-010e4416f13f@linux.ibm.com
2023-03-30powerpc/rtas: fix miswording in rtas_function kerneldocNathan Lynch
The 'filter' member is a pointer, not a bool; fix the wording accordingly. Signed-off-by: Nathan Lynch <nathanl@linux.ibm.com> Reviewed-by: Andrew Donnellan <ajd@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20230220-rtas-queue-for-6-4-v1-4-010e4416f13f@linux.ibm.com
2023-03-30powerpc/rtas: rtas_call_unlocked() kerneldocNathan Lynch
Add documentation for rtas_call_unlocked(), including details on how it differs from rtas_call(). Signed-off-by: Nathan Lynch <nathanl@linux.ibm.com> Reviewed-by: Andrew Donnellan <ajd@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20230220-rtas-queue-for-6-4-v1-3-010e4416f13f@linux.ibm.com
2023-03-30powerpc/rtas: use memmove for potentially overlapping buffer copyNathan Lynch
Using memcpy() isn't safe when buf is identical to rtas_err_buf, which can happen during boot before slab is up. Full context which may not be obvious from the diff: if (altbuf) { buf = altbuf; } else { buf = rtas_err_buf; if (slab_is_available()) buf = kmalloc(RTAS_ERROR_LOG_MAX, GFP_ATOMIC); } if (buf) memcpy(buf, rtas_err_buf, RTAS_ERROR_LOG_MAX); This was found by inspection and I'm not aware of it causing problems in practice. It appears to have been introduced by commit 033ef338b6e0 ("powerpc: Merge rtas.c into arch/powerpc/kernel"); the old ppc64 version of this code did not have this problem. Use memmove() instead. Fixes: 033ef338b6e0 ("powerpc: Merge rtas.c into arch/powerpc/kernel") Signed-off-by: Nathan Lynch <nathanl@linux.ibm.com> Reviewed-by: Andrew Donnellan <ajd@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20230220-rtas-queue-for-6-4-v1-2-010e4416f13f@linux.ibm.com
2023-03-28lazy tlb: introduce lazy tlb mm refcount helper functionsNicholas Piggin
Add explicit _lazy_tlb annotated functions for lazy tlb mm refcounting. This makes the lazy tlb mm references more obvious, and allows the refcounting scheme to be modified in later changes. There is no functional change with this patch. Link: https://lkml.kernel.org/r/20230203071837.1136453-3-npiggin@gmail.com Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Nadav Amit <nadav.amit@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-03-28powerpc: Don't try to copy PPR for task with NULL pt_regsJens Axboe
powerpc sets up PF_KTHREAD and PF_IO_WORKER with a NULL pt_regs, which from my (arguably very short) checking is not commonly done for other archs. This is fine, except when PF_IO_WORKER's have been created and the task does something that causes a coredump to be generated. Then we get this crash: Kernel attempted to read user page (160) - exploit attempt? (uid: 1000) BUG: Kernel NULL pointer dereference on read at 0x00000160 Faulting instruction address: 0xc0000000000c3a60 Oops: Kernel access of bad area, sig: 11 [#1] LE PAGE_SIZE=64K MMU=Radix SMP NR_CPUS=32 NUMA pSeries Modules linked in: bochs drm_vram_helper drm_kms_helper xts binfmt_misc ecb ctr syscopyarea sysfillrect cbc sysimgblt drm_ttm_helper aes_generic ttm sg libaes evdev joydev virtio_balloon vmx_crypto gf128mul drm dm_mod fuse loop configfs drm_panel_orientation_quirks ip_tables x_tables autofs4 hid_generic usbhid hid xhci_pci xhci_hcd usbcore usb_common sd_mod CPU: 1 PID: 1982 Comm: ppc-crash Not tainted 6.3.0-rc2+ #88 Hardware name: IBM pSeries (emulated by qemu) POWER9 (raw) 0x4e1202 0xf000005 of:SLOF,HEAD hv:linux,kvm pSeries NIP: c0000000000c3a60 LR: c000000000039944 CTR: c0000000000398e0 REGS: c0000000041833b0 TRAP: 0300 Not tainted (6.3.0-rc2+) MSR: 800000000280b033 <SF,VEC,VSX,EE,FP,ME,IR,DR,RI,LE> CR: 88082828 XER: 200400f8 ... NIP memcpy_power7+0x200/0x7d0 LR ppr_get+0x64/0xb0 Call Trace: ppr_get+0x40/0xb0 (unreliable) __regset_get+0x180/0x1f0 regset_get_alloc+0x64/0x90 elf_core_dump+0xb98/0x1b60 do_coredump+0x1c34/0x24a0 get_signal+0x71c/0x1410 do_notify_resume+0x140/0x6f0 interrupt_exit_user_prepare_main+0x29c/0x320 interrupt_exit_user_prepare+0x6c/0xa0 interrupt_return_srr_user+0x8/0x138 Because ppr_get() is trying to copy from a PF_IO_WORKER with a NULL pt_regs. Check for a valid pt_regs in both ppc_get/ppr_set, and return an error if not set. The actual error value doesn't seem to be important here, so just pick -EINVAL. Fixes: fa439810cc1b ("powerpc/ptrace: Enable support for NT_PPPC_TAR, NT_PPC_PPR, NT_PPC_DSCR") Cc: stable@vger.kernel.org # v4.8+ Signed-off-by: Jens Axboe <axboe@kernel.dk> [mpe: Trim oops in change log, add Fixes & Cc stable] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/d9f63344-fe7c-56ae-b420-4a1a04a2ae4c@kernel.dk
2023-03-24treewide: Trace IPIs sent via smp_send_reschedule()Valentin Schneider
To be able to trace invocations of smp_send_reschedule(), rename the arch-specific definitions of it to arch_smp_send_reschedule() and wrap it into an smp_send_reschedule() that contains a tracepoint. Changes to include the declaration of the tracepoint were driven by the following coccinelle script: @func_use@ @@ smp_send_reschedule(...); @include@ @@ #include <trace/events/ipi.h> @no_include depends on func_use && !include@ @@ #include <...> + + #include <trace/events/ipi.h> [csky bits] [riscv bits] Signed-off-by: Valentin Schneider <vschneid@redhat.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Guo Ren <guoren@kernel.org> Acked-by: Palmer Dabbelt <palmer@rivosinc.com> Link: https://lore.kernel.org/r/20230307143558.294354-6-vschneid@redhat.com
2023-03-23kasan, powerpc: don't rename memintrinsics if compiler adds prefixesMarco Elver
With appropriate compiler support [1], KASAN builds use __asan prefixed meminstrinsics, and KASAN no longer overrides memcpy/memset/memmove. If compiler support is detected (CC_HAS_KASAN_MEMINTRINSIC_PREFIX), define memintrinsics normally (do not prefix '__'). On powerpc, KASAN is the only user of __mem functions, which are used to define instrumented memintrinsics. Alias the normal versions for KASAN to use in its implementation. Link: https://lore.kernel.org/all/20230224085942.1791837-1-elver@google.com/ [1] Link: https://lore.kernel.org/oe-kbuild-all/202302271348.U5lvmo0S-lkp@intel.com/ Link: https://lkml.kernel.org/r/20230227094726.3833247-1-elver@google.com Signed-off-by: Marco Elver <elver@google.com> Reported-by: kernel test robot <lkp@intel.com> Acked-by: Michael Ellerman <mpe@ellerman.id.au> [powerpc] Cc: Alexander Potapenko <glider@google.com> Cc: Andrey Konovalov <andreyknvl@gmail.com> Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com> Cc: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: Daniel Axtens <dja@axtens.net> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Liam R. Howlett <Liam.Howlett@oracle.com> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Vincenzo Frascino <vincenzo.frascino@arm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-03-21vdso: Improve cmd_vdso_check to check all dynamic relocationsFangrui Song
The actual intention is that no dynamic relocation exists in the VDSO. For this the VDSO build validates that the resulting .so file does not have any relocations which are specified via $(ARCH_REL_TYPE_ABS) per architecture, which is fragile as e.g. ARM64 lacks an entry for R_AARCH64_RELATIVE. Aside of that ARCH_REL_TYPE_ABS is a misnomer as it checks for relative relocations too. However, some GNU ld ports produce unneeded R_*_NONE relocation entries. If a port fails to determine the exact .rel[a].dyn size, the trailing zeros become R_*_NONE relocations. E.g. ld's powerpc port recently fixed https://sourceware.org/bugzilla/show_bug.cgi?id=29540). R_*_NONE are generally a no-op in the dynamic loaders. So just ignore them. Remove the ARCH_REL_TYPE_ABS defines and just validate that the resulting .so file does not contain any R_* relocation entries except R_*_NONE. Signed-off-by: Fangrui Song <maskray@google.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Vincenzo Frascino <vincenzo.frascino@arm.com> # for aarch64 Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu> Reviewed-by: Vincenzo Frascino <vincenzo.frascino@arm.com> # for vDSO, aarch64 Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc) Link: https://lore.kernel.org/r/20230310190750.3323802-1-maskray@google.com
2023-03-17powerpc/sysfs: move to use bus_get_dev_root()Greg Kroah-Hartman
Direct access to the struct bus_type dev_root pointer is going away soon so replace that with a call to bus_get_dev_root() instead, which is what it is there for. Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: David Hildenbrand <david@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: linuxppc-dev@lists.ozlabs.org Link: https://lore.kernel.org/r/20230313182918.1312597-12-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-03-16powerpc: Simplify sysctl registration for powersave_nap_ctl_tableLuis Chamberlain
There is no need to declare an extra tables to just create directory, this can be easily be done with a prefix path with register_sysctl(). Simplify this registration. Signed-off-by: Luis Chamberlain <mcgrof@kernel.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20230310232850.3960676-2-mcgrof@kernel.org
2023-03-16powerpc: Make generic_calibrate_decr() the defaultChristophe Leroy
ppc_md.calibrate_decr() is a mandatory item. Its nullity is never checked so it must be non null on all platforms. Most platforms define generic_calibrate_decr() as their ppc_md.calibrate_decr(). Have time_init() call generic_calibrate_decr() when ppc_md.calibrate_decr() is NULL, and remove default assignment from all machines. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/6cb9865d916231c38401ba34ad1a98c249fae135.1676711562.git.christophe.leroy@csgroup.eu
2023-03-15powerpc/machdep: Define 'compatible' property in ppc_md and use itChristophe Leroy
Most probe functions do nothing else than checking whether the machine is compatible to a given string. Define that string in ppc_md structure and check it directly from probe_machine() instead of using ppc_md.probe() for that. Keep checking in ppc_md.probe() only for more complex probing. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/6cb9865d916231c38401ba34ad1a98c249fae135.1676711562.git.christophe.leroy@csgroup.eu
2023-03-15powerpc: Fix a kernel-doc warningBo Liu
The current code provokes a kernel-doc warnings: arch/powerpc/kernel/process.c:1606: warning: This comment starts with '/**', but isn't a kernel-doc comment. Refer Documentation/doc-guide/kernel-doc.rst Signed-off-by: Bo Liu <liubo03@inspur.com> Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20221101015452.3216-1-liubo03@inspur.com
2023-03-15powerpc/iommu: Add iommu_ops to report capabilities and allow blocking domainsAlexey Kardashevskiy
Up until now PPC64 managed to avoid using iommu_ops. The VFIO driver uses a SPAPR TCE sub-driver and all iommu_ops uses were kept in the Type1 VFIO driver. Recent development added 2 uses of iommu_ops to the generic VFIO which broke POWER: - a coherency capability check; - blocking IOMMU domain - iommu_group_dma_owner_claimed()/... This adds a simple iommu_ops which reports support for cache coherency and provides a basic support for blocking domains. No other domain types are implemented so the default domain is NULL. Since now iommu_ops controls the group ownership, this takes it out of VFIO. This adds an IOMMU device into a pci_controller (=PHB) and registers it in the IOMMU subsystem, iommu_ops is registered at this point. This setup is done in postcore_initcall_sync. This replaces iommu_group_add_device() with iommu_probe_device() as the former misses necessary steps in connecting PCI devices to IOMMU devices. This adds a comment about why explicit iommu_probe_device() is still needed. The previous discussion is here: https://lore.kernel.org/r/20220707135552.3688927-1-aik@ozlabs.ru/ https://lore.kernel.org/r/20220701061751.1955857-1-aik@ozlabs.ru/ Fixes: e8ae0e140c05 ("vfio: Require that devices support DMA cache coherence") Fixes: 70693f470848 ("vfio: Set DMA ownership for VFIO devices") Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> Signed-off-by: Timothy Pearson <tpearson@raptorengineering.com> Acked-by: Alex Williamson <alex.williamson@redhat.com> [mpe: Fix CONFIG_IOMMU_API=n build] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/2000135730.16998523.1678123860135.JavaMail.zimbra@raptorengineeringinc.com
2023-03-14powerpc/pci_64: Init pcibios subsys a bit laterAlexey Kardashevskiy
Subsequent patches are going to add dependency/use of iommu_ops which is initialized in subsys_initcall as well. This moves pciobios_init() to the next initcall level. This should not cause behavioral change. Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> Signed-off-by: Timothy Pearson <tpearson@raptorengineering.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/12303156.16998521.1678123842049.JavaMail.zimbra@raptorengineeringinc.com
2023-03-14powerpc/iommu: Add "borrowing" iommu_table_group_opsAlexey Kardashevskiy
PPC64 IOMMU API defines iommu_table_group_ops which handles DMA windows for PEs: control the ownership, create/set/unset a table the hardware for dynamic DMA windows (DDW). VFIO uses the API to implement support on POWER. So far only PowerNV IODA2 (POWER8 and newer machines) implemented this and other cases (POWER7 or nested KVM) did not and instead reused existing iommu_table structs. This means 1) no DDW 2) ownership transfer is done directly in the VFIO SPAPR TCE driver. Soon POWER is going to get its own iommu_ops and ownership control is going to move there. This implements spapr_tce_table_group_ops which borrows iommu_table tables. The upside is that VFIO needs to know less about POWER. The new ops returns the existing table from create_table() and only checks if the same window is already set. This is only going to work if the default DMA window starts table_group.tce32_start and as big as pe->table_group.tce32_size (not the case for IODA2+ PowerNV). This changes iommu_table_group_ops::take_ownership() to return an error if borrowing a table failed. This should not cause any visible change in behavior for PowerNV. pSeries was not that well tested/supported anyway. Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> Signed-off-by: Timothy Pearson <tpearson@raptorengineering.com> Acked-by: Alex Williamson <alex.williamson@redhat.com> [mpe: Fix CONFIG_IOMMU_API=n build (skiroot_defconfig), & formatting] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/525438831.16998517.1678123820075.JavaMail.zimbra@raptorengineeringinc.com
2023-03-09module: replace module_layout with module_memorySong Liu
module_layout manages different types of memory (text, data, rodata, etc.) in one allocation, which is problematic for some reasons: 1. It is hard to enable CONFIG_STRICT_MODULE_RWX. 2. It is hard to use huge pages in modules (and not break strict rwx). 3. Many archs uses module_layout for arch-specific data, but it is not obvious how these data are used (are they RO, RX, or RW?) Improve the scenario by replacing 2 (or 3) module_layout per module with up to 7 module_memory per module: MOD_TEXT, MOD_DATA, MOD_RODATA, MOD_RO_AFTER_INIT, MOD_INIT_TEXT, MOD_INIT_DATA, MOD_INIT_RODATA, and allocating them separately. This adds slightly more entries to mod_tree (from up to 3 entries per module, to up to 7 entries per module). However, this at most adds a small constant overhead to __module_address(), which is expected to be fast. Various archs use module_layout for different data. These data are put into different module_memory based on their location in module_layout. IOW, data that used to go with text is allocated with MOD_MEM_TYPE_TEXT; data that used to go with data is allocated with MOD_MEM_TYPE_DATA, etc. module_memory simplifies quite some of the module code. For example, ARCH_WANTS_MODULES_DATA_IN_VMALLOC is a lot cleaner, as it just uses a different allocator for the data. kernel/module/strict_rwx.c is also much cleaner with module_memory. Signed-off-by: Song Liu <song@kernel.org> Cc: Luis Chamberlain <mcgrof@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Guenter Roeck <linux@roeck-us.net> Cc: Christophe Leroy <christophe.leroy@csgroup.eu> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu> Reviewed-by: Luis Chamberlain <mcgrof@kernel.org> Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
2023-03-08sched/idle: Mark arch_cpu_idle_dead() __noreturnJosh Poimboeuf
Before commit 076cbf5d2163 ("x86/xen: don't let xen_pv_play_dead() return"), in Xen, when a previously offlined CPU was brought back online, it unexpectedly resumed execution where it left off in the middle of the idle loop. There were some hacks to make that work, but the behavior was surprising as do_idle() doesn't expect an offlined CPU to return from the dead (in arch_cpu_idle_dead()). Now that Xen has been fixed, and the arch-specific implementations of arch_cpu_idle_dead() also don't return, give it a __noreturn attribute. This will cause the compiler to complain if an arch-specific implementation might return. It also improves code generation for both caller and callee. Also fixes the following warning: vmlinux.o: warning: objtool: do_idle+0x25f: unreachable instruction Reported-by: Paul E. McKenney <paulmck@kernel.org> Tested-by: Paul E. McKenney <paulmck@kernel.org> Link: https://lore.kernel.org/r/60d527353da8c99d4cf13b6473131d46719ed16d.1676358308.git.jpoimboe@kernel.org Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
2023-03-04Merge tag 'powerpc-6.3-2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc fixes from Michael Ellerman: - Drop orphaned VAS MAINTAINERS entry - Fix build errors with clang and KCSAN - Avoid build errors seen with LD_DEAD_CODE_DATA_ELIMINATION together with recordmcount Thanks to Nathan Chancellor. * tag 'powerpc-6.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: powerpc: Avoid dead code/data elimination when using recordmcount powerpc/vmlinux.lds: Add .text.asan/tsan sections powerpc: Drop orphaned VAS MAINTAINERS entry