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2024-07-03um: Remove unused ncpus variableTiwei Bie
It's no longer used. And uml_ncpus_setup doesn't exist anymore. Signed-off-by: Tiwei Bie <tiwei.btw@antgroup.com> Link: https://patch.msgid.link/20240527134024.1539848-2-tiwei.btw@antgroup.com Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2024-04-22um: Fix -Wmissing-prototypes warnings for text_poke*Tiwei Bie
The prototypes for text_poke* are declared in asm/text-patching.h under arch/x86/include/. It's safe to include this header, as it's UML-aware (by checking CONFIG_UML_X86). This will address below -Wmissing-prototypes warnings: arch/um/kernel/um_arch.c:461:7: warning: no previous prototype for ‘text_poke’ [-Wmissing-prototypes] arch/um/kernel/um_arch.c:473:6: warning: no previous prototype for ‘text_poke_sync’ [-Wmissing-prototypes] Signed-off-by: Tiwei Bie <tiwei.btw@antgroup.com> Signed-off-by: Richard Weinberger <richard@nod.at>
2024-01-08mm, treewide: rename MAX_ORDER to MAX_PAGE_ORDERKirill A. Shutemov
commit 23baf831a32c ("mm, treewide: redefine MAX_ORDER sanely") has changed the definition of MAX_ORDER to be inclusive. This has caused issues with code that was not yet upstream and depended on the previous definition. To draw attention to the altered meaning of the define, rename MAX_ORDER to MAX_PAGE_ORDER. Link: https://lkml.kernel.org/r/20231228144704.14033-2-kirill.shutemov@linux.intel.com Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-07-10x86/alternative: Rename apply_ibt_endbr()Peter Zijlstra
The current name doesn't reflect what it does very well. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Kees Cook <keescook@chromium.org> Reviewed-by: Sami Tolvanen <samitolvanen@google.com> Link: https://lkml.kernel.org/r/20230622144321.427441595%40infradead.org
2023-06-16um/cpu: Switch to arch_cpu_finalize_init()Thomas Gleixner
check_bugs() is about to be phased out. Switch over to the new arch_cpu_finalize_init() implementation. No functional change. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Richard Weinberger <richard@nod.at> Link: https://lore.kernel.org/r/20230613224545.493148694@linutronix.de
2023-04-20um: make stub data pages size tweakableJohannes Berg
There's a lot of code here that hard-codes that the data is a single page, and right now that seems to be sufficient, but to make it easier to change this in the future, add a new STUB_DATA_PAGES constant and use it throughout the code. Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: Richard Weinberger <richard@nod.at>
2023-02-10um: Make the definition of cpu_data more compatiblePeter Foley
Match the x86 implementation to improve build errors. Noticed when building allyesconfig. e.g. ../arch/um/include/asm/processor-generic.h:94:19: error: called object is not a function or function pointer 94 | #define cpu_data (&boot_cpu_data) | ~^~~~~~~~~~~~~~~ ../drivers/gpu/drm/amd/amdgpu/../amdkfd/kfd_topology.c:2157:16: note: in expansion of macro ‘cpu_data’ 2157 | return cpu_data(first_cpu_of_numa_node).apicid; Signed-off-by: Peter Foley <pefoley2@pefoley.com> Signed-off-by: Richard Weinberger <richard@nod.at>
2022-11-01x86/ibt: Implement FineIBTPeter Zijlstra
Implement an alternative CFI scheme that merges both the fine-grained nature of kCFI but also takes full advantage of the coarse grained hardware CFI as provided by IBT. To contrast: kCFI is a pure software CFI scheme and relies on being able to read text -- specifically the instruction *before* the target symbol, and does the hash validation *before* doing the call (otherwise control flow is compromised already). FineIBT is a software and hardware hybrid scheme; by ensuring every branch target starts with a hash validation it is possible to place the hash validation after the branch. This has several advantages: o the (hash) load is avoided; no memop; no RX requirement. o IBT WAIT-FOR-ENDBR state is a speculation stop; by placing the hash validation in the immediate instruction after the branch target there is a minimal speculation window and the whole is a viable defence against SpectreBHB. o Kees feels obliged to mention it is slightly more vulnerable when the attacker can write code. Obviously this patch relies on kCFI, but additionally it also relies on the padding from the call-depth-tracking patches. It uses this padding to place the hash-validation while the call-sites are re-written to modify the indirect target to be 16 bytes in front of the original target, thus hitting this new preamble. Notably, there is no hardware that needs call-depth-tracking (Skylake) and supports IBT (Tigerlake and onwards). Suggested-by: Joao Moreira (Intel) <joao@overdrivepizza.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/20221027092842.634714496@infradead.org
2022-10-14Merge tag 'for-linus-6.1-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/uml/linux Pull UML updates from Richard Weinberger: - Move to strscpy() - Improve panic notifiers - Fix NR_CPUS usage - Fixes for various comments - Fixes for virtio driver * tag 'for-linus-6.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/uml/linux: uml: Remove the initialization of statics to 0 um: Do not initialise statics to 0. um: Fix comment typo um: Improve panic notifiers consistency and ordering um: remove unused reactivate_chan() declaration um: mmaper: add __exit annotations to module exit funcs um: virt-pci: add __init/__exit annotations to module init/exit funcs hostfs: move from strlcpy with unused retval to strscpy um: move from strlcpy with unused retval to strscpy um: increase default virtual physical memory to 64 MiB UM: cpuinfo: Fix a warning for CONFIG_CPUMASK_OFFSTACK um: read multiple msg from virtio slave request fd
2022-09-19um: Improve panic notifiers consistency and orderingGuilherme G. Piccoli
Currently the panic notifiers from user mode linux don't follow the convention for most of the other notifiers present in the kernel (indentation, priority setting, numeric return). More important, the priorities could be improved, since it's a special case (userspace), hence we could run the notifiers earlier; user mode linux shouldn't care much with other panic notifiers but the ordering among the mconsole and arch notifier is important, given that the arch one effectively triggers a core dump. Fix that by running the mconsole notifier as the first panic notifier, followed by the architecture one (that coredumps). Cc: Anton Ivanov <anton.ivanov@cambridgegreys.com> Cc: Johannes Berg <johannes@sipsolutions.net> Cc: Richard Weinberger <richard@nod.at> Signed-off-by: Guilherme G. Piccoli <gpiccoli@igalia.com> V3: - No changes. V2: - Kept the notifier header to avoid implicit usage - thanks Johannes for the suggestion! Signed-off-by: Richard Weinberger <richard@nod.at>
2022-09-19um: move from strlcpy with unused retval to strscpyWolfram Sang
Follow the advice of the below link and prefer 'strscpy' in this subsystem. Conversion is 1:1 because the return value is not used. Generated by a coccinelle script. Link: https://lore.kernel.org/r/CAHk-=wgfRnXz0W3D37d01q3JFkr_i_uTL=V6A6G1oUZcprmknw@mail.gmail.com/ Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Signed-off-by: Richard Weinberger <richard@nod.at>
2022-09-19um: increase default virtual physical memory to 64 MiBChristian Lamparter
The current 32 MiB of RAM causes OOMs to appear shortly after booting in a minimal OpenWrt 22.03 configuration with a 5.10.134 kernel. Of course, passing a "mem=64M" (from the --help text) parameter works too, but it produces the following (info) message: | [ 0.000000] Unknown kernel command line parameters "mem=64M", will be passed to user space. That's why, I think it would be nicer, if this is working out of the box again :). Signed-off-by: Christian Lamparter <chunkeey@gmail.com> Signed-off-by: Richard Weinberger <richard@nod.at>
2022-09-19um: fix default console kernel parameterChristian Lamparter
OpenWrt's UML with 5.15 was producing odd errors/warnings during preinit part of the early userspace portion: |[ 0.000000] Kernel command line: ubd0=root.img root=98:0 console=tty |[...] |[ 0.440000] random: jshn: uninitialized urandom read (4 bytes read) |[ 0.460000] random: jshn: uninitialized urandom read (4 bytes read) |/etc/preinit: line 47: can't create /dev/tty: No such device or address |/etc/preinit: line 48: can't create /dev/tty: No such device or address |/etc/preinit: line 58: can't open /dev/tty: No such device or address |[...] repeated many times That "/dev/tty" came from the command line (which is automatically added if no console= parameter was specified for the uml binary). The TLDP project tells the following about the /dev/tty: <https://tldp.org/HOWTO/Text-Terminal-HOWTO-7.html#ss7.3> | /dev/tty stands for the controlling terminal (if any) for the current | process.[...] | /dev/tty is something like a link to the actually terminal device[..] The "(if any)" is important here, since it's possible for processes to not have a controlling terminal. I think this was a simple typo and the author wanted tty0 there. CC: Thomas Meyer <thomas@m3y3r.de> Fixes: d7ffac33631b ("um: stdio_console: Make preferred console") Signed-off-by: Christian Lamparter <chunkeey@gmail.com> Signed-off-by: Richard Weinberger <richard@nod.at>
2022-09-19UM: cpuinfo: Fix a warning for CONFIG_CPUMASK_OFFSTACKHuacai Chen
When CONFIG_CPUMASK_OFFSTACK and CONFIG_DEBUG_PER_CPU_MAPS is selected, cpu_max_bits_warn() generates a runtime warning similar as below while we show /proc/cpuinfo. Fix this by using nr_cpu_ids (the runtime limit) instead of NR_CPUS to iterate CPUs. [ 3.052463] ------------[ cut here ]------------ [ 3.059679] WARNING: CPU: 3 PID: 1 at include/linux/cpumask.h:108 show_cpuinfo+0x5e8/0x5f0 [ 3.070072] Modules linked in: efivarfs autofs4 [ 3.076257] CPU: 0 PID: 1 Comm: systemd Not tainted 5.19-rc5+ #1052 [ 3.099465] Stack : 9000000100157b08 9000000000f18530 9000000000cf846c 9000000100154000 [ 3.109127] 9000000100157a50 0000000000000000 9000000100157a58 9000000000ef7430 [ 3.118774] 90000001001578e8 0000000000000040 0000000000000020 ffffffffffffffff [ 3.128412] 0000000000aaaaaa 1ab25f00eec96a37 900000010021de80 900000000101c890 [ 3.138056] 0000000000000000 0000000000000000 0000000000000000 0000000000aaaaaa [ 3.147711] ffff8000339dc220 0000000000000001 0000000006ab4000 0000000000000000 [ 3.157364] 900000000101c998 0000000000000004 9000000000ef7430 0000000000000000 [ 3.167012] 0000000000000009 000000000000006c 0000000000000000 0000000000000000 [ 3.176641] 9000000000d3de08 9000000001639390 90000000002086d8 00007ffff0080286 [ 3.186260] 00000000000000b0 0000000000000004 0000000000000000 0000000000071c1c [ 3.195868] ... [ 3.199917] Call Trace: [ 3.203941] [<90000000002086d8>] show_stack+0x38/0x14c [ 3.210666] [<9000000000cf846c>] dump_stack_lvl+0x60/0x88 [ 3.217625] [<900000000023d268>] __warn+0xd0/0x100 [ 3.223958] [<9000000000cf3c90>] warn_slowpath_fmt+0x7c/0xcc [ 3.231150] [<9000000000210220>] show_cpuinfo+0x5e8/0x5f0 [ 3.238080] [<90000000004f578c>] seq_read_iter+0x354/0x4b4 [ 3.245098] [<90000000004c2e90>] new_sync_read+0x17c/0x1c4 [ 3.252114] [<90000000004c5174>] vfs_read+0x138/0x1d0 [ 3.258694] [<90000000004c55f8>] ksys_read+0x70/0x100 [ 3.265265] [<9000000000cfde9c>] do_syscall+0x7c/0x94 [ 3.271820] [<9000000000202fe4>] handle_syscall+0xc4/0x160 [ 3.281824] ---[ end trace 8b484262b4b8c24c ]--- Cc: stable@vger.kernel.org Signed-off-by: Huacai Chen <chenhuacai@loongson.cn> Signed-off-by: Richard Weinberger <richard@nod.at>
2022-08-02Merge tag 'random-6.0-rc1-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/crng/random Pull random number generator updates from Jason Donenfeld: "Though there's been a decent amount of RNG-related development during this last cycle, not all of it is coming through this tree, as this cycle saw a shift toward tackling early boot time seeding issues, which took place in other trees as well. Here's a summary of the various patches: - The CONFIG_ARCH_RANDOM .config option and the "nordrand" boot option have been removed, as they overlapped with the more widely supported and more sensible options, CONFIG_RANDOM_TRUST_CPU and "random.trust_cpu". This change allowed simplifying a bit of arch code. - x86's RDRAND boot time test has been made a bit more robust, with RDRAND disabled if it's clearly producing bogus results. This would be a tip.git commit, technically, but I took it through random.git to avoid a large merge conflict. - The RNG has long since mixed in a timestamp very early in boot, on the premise that a computer that does the same things, but does so starting at different points in wall time, could be made to still produce a different RNG state. Unfortunately, the clock isn't set early in boot on all systems, so now we mix in that timestamp when the time is actually set. - User Mode Linux now uses the host OS's getrandom() syscall to generate a bootloader RNG seed and later on treats getrandom() as the platform's RDRAND-like faculty. - The arch_get_random_{seed_,}_long() family of functions is now arch_get_random_{seed_,}_longs(), which enables certain platforms, such as s390, to exploit considerable performance advantages from requesting multiple CPU random numbers at once, while at the same time compiling down to the same code as before on platforms like x86. - A small cleanup changing a cmpxchg() into a try_cmpxchg(), from Uros. - A comment spelling fix" More info about other random number changes that come in through various architecture trees in the full commentary in the pull request: https://lore.kernel.org/all/20220731232428.2219258-1-Jason@zx2c4.com/ * tag 'random-6.0-rc1-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/crng/random: random: correct spelling of "overwrites" random: handle archrandom with multiple longs um: seed rng using host OS rng random: use try_cmpxchg in _credit_init_bits timekeeping: contribute wall clock to rng on time change x86/rdrand: Remove "nordrand" flag in favor of "random.trust_cpu" random: remove CONFIG_ARCH_RANDOM
2022-07-18um: seed rng using host OS rngJason A. Donenfeld
UML generally does not provide access to special CPU instructions like RDRAND, and execution tends to be rather deterministic, with no real hardware interrupts, making good randomness really very hard, if not all together impossible. Not only is this a security eyebrow raiser, but it's also quite annoying when trying to do various pieces of UML-based automation that takes a long time to boot, if ever. Fix this by trivially calling getrandom() in the host and using that seed as "bootloader randomness", which initializes the rng immediately at UML boot. The old behavior can be restored the same way as on any other arch, by way of CONFIG_TRUST_BOOTLOADER_RANDOMNESS=n or random.trust_bootloader=0. So seen from that perspective, this just makes UML act like other archs, which is positive in its own right. Additionally, wire up arch_get_random_{int,long}() in the same way, so that reseeds can also make use of the host RNG, controllable by CONFIG_TRUST_CPU_RANDOMNESS and random.trust_cpu, per usual. Cc: stable@vger.kernel.org Acked-by: Johannes Berg <johannes@sipsolutions.net> Acked-By: Anton Ivanov <anton.ivanov@cambridgegreys.com> Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2022-07-14um: Add missing apply_returns()Peter Zijlstra
Implement apply_returns() stub for UM, just like all the other patching routines. Fixes: 15e67227c49a ("x86: Undo return-thunk damage") Reported-by: Randy Dunlap <rdunlap@infradead.org) Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Borislav Petkov <bp@suse.de> Link: https://lore.kernel.org/r/Ys%2Ft45l%2FgarIrD0u@worktop.programming.kicks-ass.net
2022-03-15x86/alternative: Use .ibt_endbr_seal to seal indirect callsPeter Zijlstra
Objtool's --ibt option generates .ibt_endbr_seal which lists superfluous ENDBR instructions. That is those instructions for which the function is never indirectly called. Overwrite these ENDBR instructions with a NOP4 such that these function can never be indirect called, reducing the number of viable ENDBR targets in the kernel. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Josh Poimboeuf <jpoimboe@redhat.com> Link: https://lore.kernel.org/r/20220308154319.822545231@infradead.org
2021-12-22um: Add devicetree supportVincent Whitchurch
Add a dtb=<filename> option to boot UML with a devicetree blob. This can be used for testing driver code using UML. Signed-off-by: Vincent Whitchurch <vincent.whitchurch@axis.com> [rw: Add dependency on CONFIG_OF] Signed-off-by: Richard Weinberger <richard@nod.at>
2021-10-28x86/alternative: Implement .retpoline_sites supportPeter Zijlstra
Rewrite retpoline thunk call sites to be indirect calls for spectre_v2=off. This ensures spectre_v2=off is as near to a RETPOLINE=n build as possible. This is the replacement for objtool writing alternative entries to ensure the same and achieves feature-parity with the previous approach. One noteworthy feature is that it relies on the thunks to be in machine order to compute the register index. Specifically, this does not yet address the Jcc __x86_indirect_thunk_* calls generated by clang, a future patch will add this. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Borislav Petkov <bp@suse.de> Acked-by: Josh Poimboeuf <jpoimboe@redhat.com> Tested-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/r/20211026120310.232495794@infradead.org
2021-07-09Merge tag 'for-linus-5.14-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml Pull UML updates from Richard Weinberger: - Support for optimized routines based on the host CPU - Support for PCI via virtio - Various fixes * tag 'for-linus-5.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml: um: remove unneeded semicolon in um_arch.c um: Remove the repeated declaration um: fix error return code in winch_tramp() um: fix error return code in slip_open() um: Fix stack pointer alignment um: implement flush_cache_vmap/flush_cache_vunmap um: add a UML specific futex implementation um: enable the use of optimized xor routines in UML um: Add support for host CPU flags and alignment um: allow not setting extra rpaths in the linux binary um: virtio/pci: enable suspend/resume um: add PCI over virtio emulation driver um: irqs: allow invoking time-travel handler multiple times um: time-travel/signals: fix ndelay() in interrupt um: expose time-travel mode to userspace side um: export signals_enabled directly um: remove unused smp_sigio_handler() declaration lib: add iomem emulation (logic_iomem) um: allow disabling NO_IOMEM
2021-07-01kernel.h: split out panic and oops helpersAndy Shevchenko
kernel.h is being used as a dump for all kinds of stuff for a long time. Here is the attempt to start cleaning it up by splitting out panic and oops helpers. There are several purposes of doing this: - dropping dependency in bug.h - dropping a loop by moving out panic_notifier.h - unload kernel.h from something which has its own domain At the same time convert users tree-wide to use new headers, although for the time being include new header back to kernel.h to avoid twisted indirected includes for existing users. [akpm@linux-foundation.org: thread_info.h needs limits.h] [andriy.shevchenko@linux.intel.com: ia64 fix] Link: https://lkml.kernel.org/r/20210520130557.55277-1-andriy.shevchenko@linux.intel.com Link: https://lkml.kernel.org/r/20210511074137.33666-1-andriy.shevchenko@linux.intel.com Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org> Co-developed-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Mike Rapoport <rppt@linux.ibm.com> Acked-by: Corey Minyard <cminyard@mvista.com> Acked-by: Christian Brauner <christian.brauner@ubuntu.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Kees Cook <keescook@chromium.org> Acked-by: Wei Liu <wei.liu@kernel.org> Acked-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Sebastian Reichel <sre@kernel.org> Acked-by: Luis Chamberlain <mcgrof@kernel.org> Acked-by: Stephen Boyd <sboyd@kernel.org> Acked-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Acked-by: Helge Deller <deller@gmx.de> # parisc Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-06-19um: remove unneeded semicolon in um_arch.cWan Jiabing
Fix following coccicheck warning: ./arch/um/kernel/um_arch.c:284:34-35: Unneeded semicolon Signed-off-by: Wan Jiabing <wanjiabing@vivo.com> Signed-off-by: Richard Weinberger <richard@nod.at>
2021-06-17um: Add support for host CPU flags and alignmentAnton Ivanov
1. Reflect host cpu flags into the UML instance so they can be used to select the correct implementations for xor, crypto, etc. 2. Reflect host cache alignment into UML instance. This is important when running 32 bit on a 64 bit host as 32 bit by default aligns to 32 while the actual alignment should be 64. Ditto for some Xeons which align at 128. Signed-off-by: Anton Ivanov <anton.ivanov@cambridgegreys.com> Signed-off-by: Richard Weinberger <richard@nod.at>
2021-02-12um: remove process stub VMAJohannes Berg
This mostly reverts the old commit 3963333fe676 ("uml: cover stubs with a VMA") which had added a VMA to the existing PTEs. However, there's no real reason to have the PTEs in the first place and the VMA cannot be 'fixed' in place, which leads to bugs that userspace could try to unmap them and be forcefully killed, or such. Also, there's a bit of an ugly hole in userspace's address space. Simplify all this: just install the stub code/page at the top of the (inner) address space, i.e. put it just above TASK_SIZE. The pages are simply hard-coded to be mapped in the userspace process we use to implement an mm context, and they're out of reach of the inner mmap/munmap/mprotect etc. since they're above TASK_SIZE. Getting rid of the VMA also makes vma_merge() no longer hit one of the VM_WARN_ON()s there because we installed a VMA while the code assumes the stack VMA is the first one. It also removes a lockdep warning about mmap_sem usage since we no longer have uml_setup_stubs() and thus no longer need to do any manipulation that would require mmap_sem in activate_mm(). Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: Richard Weinberger <richard@nod.at>
2021-01-26um: stdio_console: Make preferred consoleThomas Meyer
The addition of the "ttynull" console driver did break the ordering of the UML stdio console driver. The UML stdio console driver is added in late_initcall (7), whereby the ttynull driver is added in device_initcall (6), which always does make the ttynull driver the default console. Fix it by explicitly adding the UML stdio console as the preferred console, in case no 'console=' command line option was specified. Signed-off-by: Thomas Meyer <thomas@m3y3r.de> Signed-off-by: Richard Weinberger <richard@nod.at>
2020-12-14um: Fix build w/o CONFIG_PM_SLEEPJohannes Berg
uml_pm_wake() is unconditionally called from the SIGUSR1 wakeup handler since that's in the userspace portion of UML, and thus a bit tricky to ifdef out. Since pm_system_wakeup() can always be called (but may be an empty inline), also simply always have uml_pm_wake() to fix the build. Reported-by: Randy Dunlap <rdunlap@infradead.org> Acked-by: Randy Dunlap <rdunlap@infradead.org> # build-tested Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: Richard Weinberger <richard@nod.at>
2020-12-13um: Support suspend to RAMJohannes Berg
With all the previous bits in place, we can now also support suspend to RAM, in the sense that everything is suspended, not just most, including userspace, processes like in s2idle. Since um_idle_sleep() now waits forever, we can simply call that to "suspend" the system. As before, you can wake it up using SIGUSR1 since we're just in a pause() call that only needs to return. In order to implement selective resume from certain devices, and not have any arbitrary device interrupt wake up, suspend interrupts by removing SIGIO notification (O_ASYNC) from all the FDs that are not supposed to wake up the system. However, swap out the handler so we don't actually handle the SIGIO as an interrupt. Since we're in pause(), the mere act of receiving SIGIO wakes us up, and then after things have been restored enough, re-set O_ASYNC for all previously suspended FDs, reinstall the proper SIGIO handler, and send SIGIO to self to process anything that might now be pending. Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: Richard Weinberger <richard@nod.at>
2020-12-13um: Allow PM with suspend-to-idleJohannes Berg
In order to be able to experiment with suspend in UML, add the minimal work to be able to suspend (s2idle) an instance of UML, and be able to wake it back up from that state with the USR1 signal sent to the main UML process. Signed-off-by: Johannes Berg <johannes.berg@intel.com> Acked-By: Anton Ivanov <anton.ivanov@cambridgegreys.com> Signed-off-by: Richard Weinberger <richard@nod.at>
2020-10-25treewide: Convert macro and uses of __section(foo) to __section("foo")Joe Perches
Use a more generic form for __section that requires quotes to avoid complications with clang and gcc differences. Remove the quote operator # from compiler_attributes.h __section macro. Convert all unquoted __section(foo) uses to quoted __section("foo"). Also convert __attribute__((section("foo"))) uses to __section("foo") even if the __attribute__ has multiple list entry forms. Conversion done using the script at: https://lore.kernel.org/lkml/75393e5ddc272dc7403de74d645e6c6e0f4e70eb.camel@perches.com/2-convert_section.pl Signed-off-by: Joe Perches <joe@perches.com> Reviewed-by: Nick Desaulniers <ndesaulniers@gooogle.com> Reviewed-by: Miguel Ojeda <ojeda@kernel.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-09mm: don't include asm/pgtable.h if linux/mm.h is already includedMike Rapoport
Patch series "mm: consolidate definitions of page table accessors", v2. The low level page table accessors (pXY_index(), pXY_offset()) are duplicated across all architectures and sometimes more than once. For instance, we have 31 definition of pgd_offset() for 25 supported architectures. Most of these definitions are actually identical and typically it boils down to, e.g. static inline unsigned long pmd_index(unsigned long address) { return (address >> PMD_SHIFT) & (PTRS_PER_PMD - 1); } static inline pmd_t *pmd_offset(pud_t *pud, unsigned long address) { return (pmd_t *)pud_page_vaddr(*pud) + pmd_index(address); } These definitions can be shared among 90% of the arches provided XYZ_SHIFT, PTRS_PER_XYZ and xyz_page_vaddr() are defined. For architectures that really need a custom version there is always possibility to override the generic version with the usual ifdefs magic. These patches introduce include/linux/pgtable.h that replaces include/asm-generic/pgtable.h and add the definitions of the page table accessors to the new header. This patch (of 12): The linux/mm.h header includes <asm/pgtable.h> to allow inlining of the functions involving page table manipulations, e.g. pte_alloc() and pmd_alloc(). So, there is no point to explicitly include <asm/pgtable.h> in the files that include <linux/mm.h>. The include statements in such cases are remove with a simple loop: for f in $(git grep -l "include <linux/mm.h>") ; do sed -i -e '/include <asm\/pgtable.h>/ d' $f done Signed-off-by: Mike Rapoport <rppt@linux.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Cain <bcain@codeaurora.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Chris Zankel <chris@zankel.net> Cc: "David S. Miller" <davem@davemloft.net> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Greentime Hu <green.hu@gmail.com> Cc: Greg Ungerer <gerg@linux-m68k.org> Cc: Guan Xuetao <gxt@pku.edu.cn> Cc: Guo Ren <guoren@kernel.org> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Helge Deller <deller@gmx.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Ley Foon Tan <ley.foon.tan@intel.com> Cc: Mark Salter <msalter@redhat.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Matt Turner <mattst88@gmail.com> Cc: Max Filippov <jcmvbkbc@gmail.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Michal Simek <monstr@monstr.eu> Cc: Mike Rapoport <rppt@kernel.org> Cc: Nick Hu <nickhu@andestech.com> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: Richard Weinberger <richard@nod.at> Cc: Rich Felker <dalias@libc.org> Cc: Russell King <linux@armlinux.org.uk> Cc: Stafford Horne <shorne@gmail.com> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tony Luck <tony.luck@intel.com> Cc: Vincent Chen <deanbo422@gmail.com> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: Will Deacon <will@kernel.org> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Link: http://lkml.kernel.org/r/20200514170327.31389-1-rppt@kernel.org Link: http://lkml.kernel.org/r/20200514170327.31389-2-rppt@kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-05-08x86/module: Use text_poke() for late relocationsPeter Zijlstra
Because of late module patching, a livepatch module needs to be able to apply some of its relocations well after it has been loaded. Instead of playing games with module_{dis,en}able_ro(), use existing text poking mechanisms to apply relocations after module loading. So far only x86, s390 and Power have HAVE_LIVEPATCH but only the first two also have STRICT_MODULE_RWX. This will allow removal of the last module_disable_ro() usage in livepatch. The ultimate goal is to completely disallow making executable mappings writable. [ jpoimboe: Split up patches. Use mod state to determine whether memcpy() can be used. Implement text_poke() for UML. ] Cc: x86@kernel.org Suggested-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Joe Lawrence <joe.lawrence@redhat.com> Acked-by: Miroslav Benes <mbenes@suse.cz> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2019-09-15um: Add SPDX headers to files in arch/um/kernel/Alex Dewar
Convert files to use SPDX header. All files are licensed under the GPLv2. Signed-off-by: Alex Dewar <alex.dewar@gmx.co.uk> Signed-off-by: Richard Weinberger <richard@nod.at>
2019-09-15um: drivers: Add virtio vhost-user driverErel Geron
This module allows virtio devices to be used over a vhost-user socket. Signed-off-by: Erel Geron <erelx.geron@intel.com> Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: Richard Weinberger <richard@nod.at>
2018-01-09Construct init thread stack in the linker script rather than by unionDavid Howells
Construct the init thread stack in the linker script rather than doing it by means of a union so that ia64's init_task.c can be got rid of. The following symbols are then made available from INIT_TASK_DATA() linker script macro: init_thread_union init_stack INIT_TASK_DATA() also expands the region to THREAD_SIZE to accommodate the size of the init stack. init_thread_union is given its own section so that it can be placed into the stack space in the right order. I'm assuming that the ia64 ordering is correct and that the task_struct is first and the thread_info second. Signed-off-by: David Howells <dhowells@redhat.com> Tested-by: Tony Luck <tony.luck@intel.com> Tested-by: Will Deacon <will.deacon@arm.com> (arm64) Tested-by: Palmer Dabbelt <palmer@sifive.com> Acked-by: Thomas Gleixner <tglx@linutronix.de>
2017-07-15Merge branch 'for-linus-4.13-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml Pull UML updates from Richard Weinberger: "Mostly fixes for UML: - First round of fixes for PTRACE_GETRESET/SETREGSET - A printf vs printk cleanup - Minor improvements" * 'for-linus-4.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml: um: Correctly check for PTRACE_GETRESET/SETREGSET um: v2: Use generic NOTES macro um: Add kerneldoc for userspace_tramp() and start_userspace() um: Add kerneldoc for segv_handler um: stub-data.h: remove superfluous include um: userspace - be more verbose in ptrace set regs error um: add dummy ioremap and iounmap functions um: Allow building and running on older hosts um: Avoid longjmp/setjmp symbol clashes with libpthread.a um: console: Ignore console= option um: Use os_warn to print out pre-boot warning/error messages um: Add os_warn() for pre-boot warning/error messages um: Use os_info for the messages on normal path um: Add os_info() for pre-boot information messages um: Use printk instead of printf in make_uml_dir
2017-07-05um: Use os_warn to print out pre-boot warning/error messagesMasami Hiramatsu
Use os_warn() instead of printf/fprintf to print out pre-boot warning/error messages to stderr. Note that the help message and version message are kept to print out to stdout, because user explicitly specifies those options to get such information. Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Richard Weinberger <richard@nod.at>
2017-07-05um: Use os_info for the messages on normal pathMasami Hiramatsu
Use os_info() for printing out the messages on the normal execution path. Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Richard Weinberger <richard@nod.at>
2017-06-28arch: remove unused macro/function thread_saved_pc()Tobias Klauser
The only user of thread_saved_pc() in non-arch-specific code was removed in commit 8243d5597793 ("sched/core: Remove pointless printout in sched_show_task()"). Remove the implementations as well. Some architectures use thread_saved_pc() in their arch-specific code. Leave their thread_saved_pc() intact. Signed-off-by: Tobias Klauser <tklauser@distanz.ch> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Ingo Molnar <mingo@kernel.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-05-03um: Fix to call read_initrd after init_bootmemMasami Hiramatsu
Since read_initrd() invokes alloc_bootmem() for allocating memory to load initrd image, it must be called after init_bootmem. This makes read_initrd() called directly from setup_arch() after init_bootmem() and mem_total_pages(). Cc: <stable@vger.kernel.org> Fixes: b63236972e1 ("um: Setup physical memory in setup_arch()") Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Richard Weinberger <richard@nod.at>
2017-03-02sched/headers: Prepare to move 'init_task' and 'init_thread_union' from ↵Ingo Molnar
<linux/sched.h> to <linux/sched/task.h> Update all usage sites first. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-08-04um: Setup physical memory in setup_arch()Richard Weinberger
Currently UML sets up physical memory very early, long before setup_arch() was called by the kernel main function. This can cause problems when code paths in UML's memory setup code assume that the kernel is already running. i.e. when kmemleak is enabled it will evaluate current() in free_bootmem(). That early current() is undefined and UML explodes. Solve the problem by setting up physical memory in setup_arch(), at this stage the kernel has materialized and basic infrastructure such as current() works. Signed-off-by: Richard Weinberger <richard@nod.at>
2015-05-31um: Use char[] for linker script address declarationsNicolas Iooss
The linker script defines some variables which are declared either with type char[] in include/asm-generic/sections.h or with a meaningless integer type in arch/um/include/asm/sections.h. Fix this inconsistency by declaring every variable char[]. Signed-off-by: Nicolas Iooss <nicolas.iooss_linux@m4x.org> Signed-off-by: Richard Weinberger <richard@nod.at>
2015-05-31um: Create asm/sections.hNicolas Iooss
arch/um/kernel/dyn.lds.S and arch/um/kernel/uml.lds.S define some UML-specific symbols. These symbols are used in the kernel part of UML with extern declarations. Move these declarations to a new header, asm/sections.h, like other architectures do. Signed-off-by: Nicolas Iooss <nicolas.iooss_linux@m4x.org> Signed-off-by: Richard Weinberger <richard@nod.at>
2015-04-13um: Move uml_postsetup in the init_thread stackThomas Meyer
atomic_notifier_chain_register() and uml_postsetup() do call kernel code that rely on the "current" kernel macro and a valid task_struct resp. thread_info struct. Give those functions a valid stack by moving uml_postsetup() in the init_thread stack. This moves enables a panic() call in this early code to generate a valid stacktrace, instead of crashing. E.g. when an UML kernel is started with an initrd but too few physical memory the panic() call get's actually processed. Signed-off-by: Thomas Meyer <thomas@m3y3r.de> Signed-off-by: Richard Weinberger <richard@nod.at>
2015-04-13um: add a kmsg_dumperThomas Meyer
Add a kmsg_dumper, that dumps the kmsg buffer to stdout, when no console is available. This an enables the printing of early panic() calls triggered in uml_postsetup(). When a panic() call happens so early in the UML kernel no earlyprintk/console is available yet, but with a kmsg_dumper in place the kernel message buffer will be outputted to the user, to give a better hint, of what the failure was. Signed-off-by: Thomas Meyer <thomas@m3y3r.de> Signed-off-by: Richard Weinberger <richard@nod.at>
2015-04-13um: Remove broken highmem supportRichard Weinberger
Highmem was always buggy and experimental on UML(i386). In times where 64 bit computers are default we can remove that experimental code. Signed-off-by: Richard Weinberger <richard@nod.at>
2015-04-13um: Remove broken SMP supportRichard Weinberger
At times where UML used the TT mode to operate it had kind of SMP support. It never got finished nor was stable. Let's rip out that cruft and stop confusing developers which do tree-wide SMP cleanups. If someone wants SMP support UML it has do be done from scratch. Signed-off-by: Richard Weinberger <richard@nod.at>
2015-04-13um: Remove SKAS3/4 supportRichard Weinberger
Before we had SKAS0 UML had two modes of operation TT (tracing thread) and SKAS3/4 (separated kernel address space). TT was known to be insecure and got removed a long time ago. SKAS3/4 required a few (3 or 4) patches on the host side which never went mainline. The last host patch is 10 years old. With SKAS0 mode (separated kernel address space using 0 host patches), default since 2005, SKAS3/4 is obsolete and can be removed. Signed-off-by: Richard Weinberger <richard@nod.at>
2014-10-13um: delete unnecessary bootmem struct page arrayHonggang Li
1) uml kernel bootmem managed through bootmem_data->node_bootmem_map, not the struct page array, so the array is unnecessary. 2) the bootmem struct page array has been pointed by a *local* pointer, struct page *map, in init_maps function. The array can be accessed only in init_maps's scope. As a result, uml kernel wastes about 1% of total memory. Signed-off-by: Honggang Li <enjoymindful@gmail.com> Signed-off-by: Richard Weinberger <richard@nod.at>