- 15 May, 2019 27 commits
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Masahiro Yamada authored
This prepares to move CONFIG_OPTIMIZE_INLINING from x86 to a common place. We need to eliminate potential issues beforehand. If it is enabled for arm, Clang build results in the following modpost warning: WARNING: vmlinux.o(.text+0x1124): Section mismatch in reference from the function setup_machine_tags() to the function .init.text:early_print() The function setup_machine_tags() references the function __init early_print(). This is often because setup_machine_tags lacks a __init annotation or the annotation of early_print is wrong. Link: http://lkml.kernel.org/r/20190423034959.13525-8-yamada.masahiro@socionext.comSigned-off-by:
Masahiro Yamada <yamada.masahiro@socionext.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Boris Brezillon <bbrezillon@kernel.org> Cc: Borislav Petkov <bp@suse.de> Cc: Brian Norris <computersforpeace@gmail.com> Cc: Christophe Leroy <christophe.leroy@c-s.fr> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Marek Vasut <marek.vasut@gmail.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Mathieu Malaterre <malat@debian.org> Cc: Miquel Raynal <miquel.raynal@bootlin.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Richard Weinberger <richard@nod.at> Cc: Russell King <rmk+kernel@arm.linux.org.uk> Cc: Stefan Agner <stefan@agner.ch> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by:
Andrew Morton <akpm@linux-foundation.org> Signed-off-by:
Linus Torvalds <torvalds@linux-foundation.org>
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Masahiro Yamada authored
This prepares to move CONFIG_OPTIMIZE_INLINING from x86 to a common place. We need to eliminate potential issues beforehand. If it is enabled for mips, the following errors are reported: arch/mips/mm/sc-mips.o: In function `mips_sc_prefetch_enable.part.2': sc-mips.c:(.text+0x98): undefined reference to `mips_gcr_base' sc-mips.c:(.text+0x9c): undefined reference to `mips_gcr_base' sc-mips.c:(.text+0xbc): undefined reference to `mips_gcr_base' sc-mips.c:(.text+0xc8): undefined reference to `mips_gcr_base' sc-mips.c:(.text+0xdc): undefined reference to `mips_gcr_base' arch/mips/mm/sc-mips.o:sc-mips.c:(.text.unlikely+0x44): more undefined references to `mips_gcr_base' Link: http://lkml.kernel.org/r/20190423034959.13525-7-yamada.masahiro@socionext.comSigned-off-by:
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Masahiro Yamada authored
This prepares to move CONFIG_OPTIMIZE_INLINING from x86 to a common place. We need to eliminate potential issues beforehand. Kbuild test robot has never reported -Wmaybe-uninitialized warning for this probably because vf610_nfc_run() is inlined by the x86 compiler's inlining heuristic. If CONFIG_OPTIMIZE_INLINING is enabled for a different architecture and vf610_nfc_run() is not inlined, the following warning is reported: drivers/mtd/nand/raw/vf610_nfc.c: In function `vf610_nfc_cmd': drivers/mtd/nand/raw/vf610_nfc.c:455:3: warning: `offset' may be used uninitialized in this function [-Wmaybe-uninitialized] vf610_nfc_rd_from_sram(instr->ctx.data.buf.in + offset, ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ nfc->regs + NFC_MAIN_AREA(0) + offset, ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ trfr_sz, !nfc->data_access); ~~~~~~~~~~~~~~~~~~~~~~~~~~~ Link: http://lkml.kernel.org/r/20190423034959.13525-6-yamada.masahiro@socionext.comSigned-off-by: -
Masahiro Yamada authored
This prepares to move CONFIG_OPTIMIZE_INLINING from x86 to a common place. We need to eliminate potential issues beforehand. If it is enabled for s390, the following error is reported: In file included from arch/s390/crypto/des_s390.c:19: arch/s390/include/asm/cpacf.h: In function 'cpacf_query': arch/s390/include/asm/cpacf.h:170:2: warning: asm operand 3 probably doesn't match constraints asm volatile( ^~~ arch/s390/include/asm/cpacf.h:170:2: error: impossible constraint in 'asm' Link: http://lkml.kernel.org/r/20190423034959.13525-5-yamada.masahiro@socionext.comSigned-off-by: -
Masahiro Yamada authored
This prepares to move CONFIG_OPTIMIZE_INLINING from x86 to a common place. We need to eliminate potential issues beforehand. If it is enabled for mips, the following error is reported: arch/mips/kernel/cpu-bugs64.c: In function 'mult_sh_align_mod.constprop': arch/mips/kernel/cpu-bugs64.c:33:2: error: asm operand 1 probably doesn't match constraints [-Werror] asm volatile( ^~~ arch/mips/kernel/cpu-bugs64.c:33:2: error: asm operand 1 probably doesn't match constraints [-Werror] asm volatile( ^~~ arch/mips/kernel/cpu-bugs64.c:33:2: error: impossible constraint in 'asm' asm volatile( ^~~ arch/mips/kernel/cpu-bugs64.c:33:2: error: impossible constraint in 'asm' asm volatile( ^~~ Link: http://lkml.kernel.org/r/20190423034959.13525-4-yamada.masahiro@socionext.comSigned-off-by: -
Masahiro Yamada authored
This prepares to move CONFIG_OPTIMIZE_INLINING from x86 to a common place. We need to eliminate potential issues beforehand. If it is enabled for arm64, the following errors are reported: In file included from include/linux/compiler_types.h:68, from <command-line>: arch/arm64/include/asm/jump_label.h: In function 'cpus_have_const_cap': include/linux/compiler-gcc.h:120:38: warning: asm operand 0 probably doesn't match constraints #define asm_volatile_goto(x...) do { asm goto(x); asm (""); } while (0) ^~~ arch/arm64/include/asm/jump_label.h:32:2: note: in expansion of macro 'asm_volatile_goto' asm_volatile_goto( ^~~~~~~~~~~~~~~~~ include/linux/compiler-gcc.h:120:38: error: impossible constraint in 'asm' #define asm_volatile_goto(x...) do { asm goto(x); asm (""); } while (0) ^~~ arch/arm64/include/asm/jump_label.h:32:2: note: in expansion of macro 'asm_volatile_goto' asm_volatile_goto( ^~~~~~~~~~~~~~~~~ Link: http://lkml.kernel.org/r/20190423034959.13525-3-yamada.masahiro@socionext.comSigned-off-by:Mark Rutland <mark.rutland@arm.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Boris Brezillon <bbrezillon@kernel.org> Cc: Borislav Petkov <bp@suse.de> Cc: Brian Norris <computersforpeace@gmail.com> Cc: Christophe Leroy <christophe.leroy@c-s.fr> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Marek Vasut <marek.vasut@gmail.com> Cc: Mathieu Malaterre <malat@debian.org> Cc: Miquel Raynal <miquel.raynal@bootlin.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Richard Weinberger <richard@nod.at> Cc: Russell King <rmk+kernel@arm.linux.org.uk> Cc: Stefan Agner <stefan@agner.ch> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by:
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Arnd Bergmann authored
Patch series "compiler: allow all arches to enable CONFIG_OPTIMIZE_INLINING", v3. This patch (of 11): When function tracing for IPIs is enabled, we get a warning for an overflow of the ipi_types array with the IPI_CPU_BACKTRACE type as triggered by raise_nmi(): arch/arm/kernel/smp.c: In function 'raise_nmi': arch/arm/kernel/smp.c:489:2: error: array subscript is above array bounds [-Werror=array-bounds] trace_ipi_raise(target, ipi_types[ipinr]); This is a correct warning as we actually overflow the array here. This patch raise_nmi() to call __smp_cross_call() instead of smp_cross_call(), to avoid calling into ftrace. For clarification, I'm also adding a two new code comments describing how this one is special. The warning appears to have shown up after commit e7273ff4 ("ARM: 8488/1: Make IPI_CPU_BACKTRACE a "non-secure" SGI"), which changed the number assignment from '15' to '8', but as far as I can tell has existed since the IPI tracepoints were first introduced. If we decide to backport this patch to stable kernels, we probably need to backport e7273ff4 as well. [yamada.masahiro@socionext.com: rebase on v5.1-rc1] Link: http://lkml.kernel.org/r/20190423034959.13525-2-yamada.masahiro@socionext.com Fixes: e7273ff4 ("ARM: 8488/1: Make IPI_CPU_BACKTRACE a "non-secure" SGI") Fixes: 365ec7b1 ("ARM: add IPI tracepoints") # v3.17 Signed-off-by:Arnd Bergmann <arnd@arndb.de> Signed-off-by:
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Masahiro Yamada authored
The "WITH Linux-syscall-note" should be added to headers exported to the user-space. Some kernel-space headers have "WITH Linux-syscall-note", which seems a mistake. [1] arch/x86/include/asm/hyperv-tlfs.h Commit 5a485803 ("x86/hyper-v: move hyperv.h out of uapi") moved this file out of uapi, but missed to update the SPDX License tag. [2] include/asm-generic/shmparam.h Commit 76ce2a80 ("Rename include/{uapi => }/asm-generic/shmparam.h really") moved this file out of uapi, but missed to update the SPDX License tag. [3] include/linux/qcom-geni-se.h Commit eddac5af ("soc: qcom: Add GENI based QUP Wrapper driver") added this file, but I do not see a good reason why its license tag must include "WITH Linux-syscall-note". Link: http://lkml.kernel.org/r/1554196104-3522-1-git-send-email-yamada.masahiro@socionext.comSigned-off-by:
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Arnd Bergmann authored
The select() implementation is carefully tuned to put a sensible amount of data on the stack for holding a copy of the user space fd_set, but not too large to risk overflowing the kernel stack. When building a 32-bit kernel with clang, we need a little more space than with gcc, which often triggers a warning: fs/select.c:619:5: error: stack frame size of 1048 bytes in function 'core_sys_select' [-Werror,-Wframe-larger-than=] int core_sys_select(int n, fd_set __user *inp, fd_set __user *outp, I experimentally found that for 32-bit ARM, reducing the maximum stack usage by 64 bytes keeps us reliably under the warning limit again. Link: http://lkml.kernel.org/r/20190307090146.1874906-1-arnd@arndb.deSigned-off-by:
Andi Kleen <ak@linux.intel.com> Cc: Nick Desaulniers <ndesaulniers@google.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Christoph Hellwig <hch@lst.de> Cc: Eric Dumazet <edumazet@google.com> Cc: "Darrick J. Wong" <darrick.wong@oracle.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by:
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Jiri Kosina authored
The semantics of what mincore() considers to be resident is not completely clear, but Linux has always (since 2.3.52, which is when mincore() was initially done) treated it as "page is available in page cache". That's potentially a problem, as that [in]directly exposes meta-information about pagecache / memory mapping state even about memory not strictly belonging to the process executing the syscall, opening possibilities for sidechannel attacks. Change the semantics of mincore() so that it only reveals pagecache information for non-anonymous mappings that belog to files that the calling process could (if it tried to) successfully open for writing; otherwise we'd be including shared non-exclusive mappings, which - is the sidechannel - is not the usecase for mincore(), as that's primarily used for data, not (shared) text [jkosina@suse.cz: v2] Link: http://lkml.kernel.org/r/20190312141708.6652-2-vbabka@suse.cz [mhocko@suse.com: restructure can_do_mincore() conditions] Link: http://lkml.kernel.org/r/nycvar.YFH.7.76.1903062342020.19912@cbobk.fhfr.pmSigned-off-by:
Jiri Kosina <jkosina@suse.cz> Signed-off-by:
Vlastimil Babka <vbabka@suse.cz> Acked-by:
Josh Snyder <joshs@netflix.com> Acked-by:
Michal Hocko <mhocko@suse.com> Originally-by:
Dominique Martinet <asmadeus@codewreck.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Dave Chinner <david@fromorbit.com> Cc: Kevin Easton <kevin@guarana.org> Cc: Matthew Wilcox <willy@infradead.org> Cc: Cyril Hrubis <chrubis@suse.cz> Cc: Tejun Heo <tj@kernel.org> Cc: Kirill A. Shutemov <kirill@shutemov.name> Cc: Daniel Gruss <daniel@gruss.cc> Signed-off-by:
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Dan Williams authored
When freeing a page with an order >= shuffle_page_order randomly select the front or back of the list for insertion. While the mm tries to defragment physical pages into huge pages this can tend to make the page allocator more predictable over time. Inject the front-back randomness to preserve the initial randomness established by shuffle_free_memory() when the kernel was booted. The overhead of this manipulation is constrained by only being applied for MAX_ORDER sized pages by default. [akpm@linux-foundation.org: coding-style fixes] Link: http://lkml.kernel.org/r/154899812788.3165233.9066631950746578517.stgit@dwillia2-desk3.amr.corp.intel.comSigned-off-by:
Dan Williams <dan.j.williams@intel.com> Reviewed-by:
Kees Cook <keescook@chromium.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Keith Busch <keith.busch@intel.com> Cc: Robert Elliott <elliott@hpe.com> Signed-off-by:
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Dan Williams authored
In preparation for runtime randomization of the zone lists, take all (well, most of) the list_*() functions in the buddy allocator and put them in helper functions. Provide a common control point for injecting additional behavior when freeing pages. [dan.j.williams@intel.com: fix buddy list helpers] Link: http://lkml.kernel.org/r/155033679702.1773410.13041474192173212653.stgit@dwillia2-desk3.amr.corp.intel.com [vbabka@suse.cz: remove del_page_from_free_area() migratetype parameter] Link: http://lkml.kernel.org/r/4672701b-6775-6efd-0797-b6242591419e@suse.cz Link: http://lkml.kernel.org/r/154899812264.3165233.5219320056406926223.stgit@dwillia2-desk3.amr.corp.intel.comSigned-off-by:
Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp> Acked-by:
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Dan Williams authored
Patch series "mm: Randomize free memory", v10. This patch (of 3): Randomization of the page allocator improves the average utilization of a direct-mapped memory-side-cache. Memory side caching is a platform capability that Linux has been previously exposed to in HPC (high-performance computing) environments on specialty platforms. In that instance it was a smaller pool of high-bandwidth-memory relative to higher-capacity / lower-bandwidth DRAM. Now, this capability is going to be found on general purpose server platforms where DRAM is a cache in front of higher latency persistent memory [1]. Robert offered an explanation of the state of the art of Linux interactions with memory-side-caches [2], and I copy it here: It's been a problem in the HPC space: http://www.nersc.gov/research-and-development/knl-cache-mode-performance-coe/ A kernel module called zonesort is available to try to help: https://software.intel.com/en-us/articles/xeon-phi-software and this abandoned patch series proposed that for the kernel: https://lkml.kernel.org/r/20170823100205.17311-1-lukasz.daniluk@intel.com Dan's patch series doesn't attempt to ensure buffers won't conflict, but also reduces the chance that the buffers will. This will make performance more consistent, albeit slower than "optimal" (which is near impossible to attain in a general-purpose kernel). That's better than forcing users to deploy remedies like: "To eliminate this gradual degradation, we have added a Stream measurement to the Node Health Check that follows each job; nodes are rebooted whenever their measured memory bandwidth falls below 300 GB/s." A replacement for zonesort was merged upstream in commit cc9aec03 ("x86/numa_emulation: Introduce uniform split capability"). With this numa_emulation capability, memory can be split into cache sized ("near-memory" sized) numa nodes. A bind operation to such a node, and disabling workloads on other nodes, enables full cache performance. However, once the workload exceeds the cache size then cache conflicts are unavoidable. While HPC environments might be able to tolerate time-scheduling of cache sized workloads, for general purpose server platforms, the oversubscribed cache case will be the common case. The worst case scenario is that a server system owner benchmarks a workload at boot with an un-contended cache only to see that performance degrade over time, even below the average cache performance due to excessive conflicts. Randomization clips the peaks and fills in the valleys of cache utilization to yield steady average performance. Here are some performance impact details of the patches: 1/ An Intel internal synthetic memory bandwidth measurement tool, saw a 3X speedup in a contrived case that tries to force cache conflicts. The contrived cased used the numa_emulation capability to force an instance of the benchmark to be run in two of the near-memory sized numa nodes. If both instances were placed on the same emulated they would fit and cause zero conflicts. While on separate emulated nodes without randomization they underutilized the cache and conflicted unnecessarily due to the in-order allocation per node. 2/ A well known Java server application benchmark was run with a heap size that exceeded cache size by 3X. The cache conflict rate was 8% for the first run and degraded to 21% after page allocator aging. With randomization enabled the rate levelled out at 11%. 3/ A MongoDB workload did not observe measurable difference in cache-conflict rates, but the overall throughput dropped by 7% with randomization in one case. 4/ Mel Gorman ran his suite of performance workloads with randomization enabled on platforms without a memory-side-cache and saw a mix of some improvements and some losses [3]. While there is potentially significant improvement for applications that depend on low latency access across a wide working-set, the performance may be negligible to negative for other workloads. For this reason the shuffle capability defaults to off unless a direct-mapped memory-side-cache is detected. Even then, the page_alloc.shuffle=0 parameter can be specified to disable the randomization on those systems. Outside of memory-side-cache utilization concerns there is potentially security benefit from randomization. Some data exfiltration and return-oriented-programming attacks rely on the ability to infer the location of sensitive data objects. The kernel page allocator, especially early in system boot, has predictable first-in-first out behavior for physical pages. Pages are freed in physical address order when first onlined. Quoting Kees: "While we already have a base-address randomization (CONFIG_RANDOMIZE_MEMORY), attacks against the same hardware and memory layouts would certainly be using the predictability of allocation ordering (i.e. for attacks where the base address isn't important: only the relative positions between allocated memory). This is common in lots of heap-style attacks. They try to gain control over ordering by spraying allocations, etc. I'd really like to see this because it gives us something similar to CONFIG_SLAB_FREELIST_RANDOM but for the page allocator." While SLAB_FREELIST_RANDOM reduces the predictability of some local slab caches it leaves vast bulk of memory to be predictably in order allocated. However, it should be noted, the concrete security benefits are hard to quantify, and no known CVE is mitigated by this randomization. Introduce shuffle_free_memory(), and its helper shuffle_zone(), to perform a Fisher-Yates shuffle of the page allocator 'free_area' lists when they are initially populated with free memory at boot and at hotplug time. Do this based on either the presence of a page_alloc.shuffle=Y command line parameter, or autodetection of a memory-side-cache (to be added in a follow-on patch). The shuffling is done in terms of CONFIG_SHUFFLE_PAGE_ORDER sized free pages where the default CONFIG_SHUFFLE_PAGE_ORDER is MAX_ORDER-1 i.e. 10, 4MB this trades off randomization granularity for time spent shuffling. MAX_ORDER-1 was chosen to be minimally invasive to the page allocator while still showing memory-side cache behavior improvements, and the expectation that the security implications of finer granularity randomization is mitigated by CONFIG_SLAB_FREELIST_RANDOM. The performance impact of the shuffling appears to be in the noise compared to other memory initialization work. This initial randomization can be undone over time so a follow-on patch is introduced to inject entropy on page free decisions. It is reasonable to ask if the page free entropy is sufficient, but it is not enough due to the in-order initial freeing of pages. At the start of that process putting page1 in front or behind page0 still keeps them close together, page2 is still near page1 and has a high chance of being adjacent. As more pages are added ordering diversity improves, but there is still high page locality for the low address pages and this leads to no significant impact to the cache conflict rate. [1]: https://itpeernetwork.intel.com/intel-optane-dc-persistent-memory-operating-modes/ [2]: https://lkml.kernel.org/r/AT5PR8401MB1169D656C8B5E121752FC0F8AB120@AT5PR8401MB1169.NAMPRD84.PROD.OUTLOOK.COM [3]: https://lkml.org/lkml/2018/10/12/309 [dan.j.williams@intel.com: fix shuffle enable] Link: http://lkml.kernel.org/r/154943713038.3858443.4125180191382062871.stgit@dwillia2-desk3.amr.corp.intel.com [cai@lca.pw: fix SHUFFLE_PAGE_ALLOCATOR help texts] Link: http://lkml.kernel.org/r/20190425201300.75650-1-cai@lca.pw Link: http://lkml.kernel.org/r/154899811738.3165233.12325692939590944259.stgit@dwillia2-desk3.amr.corp.intel.comSigned-off-by:Qian Cai <cai@lca.pw> Reviewed-by:
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Uladzislau Rezki (Sony) authored
vmap_lazy_nr variable has atomic_t type that is 4 bytes integer value on both 32 and 64 bit systems. lazy_max_pages() deals with "unsigned long" that is 8 bytes on 64 bit system, thus vmap_lazy_nr should be 8 bytes on 64 bit as well. Link: http://lkml.kernel.org/r/20190131162452.25879-1-urezki@gmail.comSigned-off-by:
Uladzislau Rezki (Sony) <urezki@gmail.com> Reviewed-by:
William Kucharski <william.kucharski@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Thomas Garnier <thgarnie@google.com> Cc: Oleksiy Avramchenko <oleksiy.avramchenko@sonymobile.com> Cc: Joel Fernandes <joelaf@google.com> Signed-off-by:
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Uladzislau Rezki (Sony) authored
Commit 763b218d ("mm: add preempt points into __purge_vmap_area_lazy()") introduced some preempt points, one of those is making an allocation more prioritized over lazy free of vmap areas. Prioritizing an allocation over freeing does not work well all the time, i.e. it should be rather a compromise. 1) Number of lazy pages directly influences the busy list length thus on operations like: allocation, lookup, unmap, remove, etc. 2) Under heavy stress of vmalloc subsystem I run into a situation when memory usage gets increased hitting out_of_memory -> panic state due to completely blocking of logic that frees vmap areas in the __purge_vmap_area_lazy() function. Establish a threshold passing which the freeing is prioritized back over allocation creating a balance between each other. Using vmalloc test driver in "stress mode", i.e. When all available test cases are run simultaneously on all online CPUs applying a pressure on the vmalloc subsystem, my HiKey 960 board runs out of memory due to the fact that __purge_vmap_area_lazy() logic simply is not able to free pages in time. How I run it: 1) You should build your kernel with CONFIG_TEST_VMALLOC=m 2) ./tools/testing/selftests/vm/test_vmalloc.sh stress During this test "vmap_lazy_nr" pages will go far beyond acceptable lazy_max_pages() threshold, that will lead to enormous busy list size and other problems including allocation time and so on. Link: http://lkml.kernel.org/r/20190124115648.9433-3-urezki@gmail.comSigned-off-by:
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Dan Schatzberg authored
Pressure metrics are already recorded and exposed in procfs for the entire system, but any tool which monitors cgroup pressure has to special case the root cgroup to read from procfs. This patch exposes the already recorded pressure metrics on the root cgroup. Link: http://lkml.kernel.org/r/20190510174938.3361741-1-dschatzberg@fb.comSigned-off-by:
Dan Schatzberg <dschatzberg@fb.com> Acked-by:
Johannes Weiner <hannes@cmpxchg.org> Cc: Tejun Heo <tj@kernel.org> Cc: Li Zefan <lizefan@huawei.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Signed-off-by:
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Suren Baghdasaryan authored
Psi monitor aims to provide a low-latency short-term pressure detection mechanism configurable by users. It allows users to monitor psi metrics growth and trigger events whenever a metric raises above user-defined threshold within user-defined time window. Time window and threshold are both expressed in usecs. Multiple psi resources with different thresholds and window sizes can be monitored concurrently. Psi monitors activate when system enters stall state for the monitored psi metric and deactivate upon exit from the stall state. While system is in the stall state psi signal growth is monitored at a rate of 10 times per tracking window. Min window size is 500ms, therefore the min monitoring interval is 50ms. Max window size is 10s with monitoring interval of 1s. When activated psi monitor stays active for at least the duration of one tracking window to avoid repeated activations/deactivations when psi signal is bouncing. Notifications to the users are rate-limited to one per tracking window. Link: http://lkml.kernel.org/r/20190319235619.260832-8-surenb@google.comSigned-off-by:
Suren Baghdasaryan <surenb@google.com> Signed-off-by:
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Suren Baghdasaryan authored
kthread.h can't be included in psi_types.h because it creates a circular inclusion with kthread.h eventually including psi_types.h and complaining on kthread structures not being defined because they are defined further in the kthread.h. Resolve this by removing psi_types.h inclusion from the headers included from kthread.h. Link: http://lkml.kernel.org/r/20190319235619.260832-7-surenb@google.comSigned-off-by:
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Suren Baghdasaryan authored
Introduce changed_states parameter into collect_percpu_times to track the states changed since the last update. This will be needed to detect whether polled states activated in the monitor patch. Link: http://lkml.kernel.org/r/20190319235619.260832-6-surenb@google.comSigned-off-by:
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Suren Baghdasaryan authored
Split update_stats into collect_percpu_times and update_averages for collect_percpu_times to be reused later inside psi monitor. Link: http://lkml.kernel.org/r/20190319235619.260832-5-surenb@google.comSigned-off-by:
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Suren Baghdasaryan authored
Rename psi_group structure member fields used for calculating psi totals and averages for clear distinction between them and for trigger-related fields that will be added by "psi: introduce psi monitor". [surenb@google.com: v6] Link: http://lkml.kernel.org/r/20190319235619.260832-4-surenb@google.com Link: http://lkml.kernel.org/r/20190124211518.244221-5-surenb@google.comSigned-off-by:
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Suren Baghdasaryan authored
psi_enable is not used outside of psi.c, make it static. Link: http://lkml.kernel.org/r/20190319235619.260832-3-surenb@google.comSigned-off-by:
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Suren Baghdasaryan authored
Patch series "psi: pressure stall monitors", v6. This is a respin of: https://lwn.net/ml/linux-kernel/20190308184311.144521-1-surenb%40google.com/ Android is adopting psi to detect and remedy memory pressure that results in stuttering and decreased responsiveness on mobile devices. Psi gives us the stall information, but because we're dealing with latencies in the millisecond range, periodically reading the pressure files to detect stalls in a timely fashion is not feasible. Psi also doesn't aggregate its averages at a high-enough frequency right now. This patch series extends the psi interface such that users can configure sensitive latency thresholds and use poll() and friends to be notified when these are breached. As high-frequency aggregation is costly, it implements an aggregation method that is optimized for fast, short-interval averaging, and makes the aggregation frequency adaptive, such that high-frequency updates only happen while monitored stall events are actively occurring. With these patches applied, Android can monitor for, and ward off, mounting memory shortages before they cause problems for the user. For example, using memory stall monitors in userspace low memory killer daemon (lmkd) we can detect mounting pressure and kill less important processes before device becomes visibly sluggish. In our memory stress testing psi memory monitors produce roughly 10x less false positives compared to vmpressure signals. Having ability to specify multiple triggers for the same psi metric allows other parts of Android framework to monitor memory state of the device and act accordingly. The new interface is straight-forward. The user opens one of the pressure files for writing and writes a trigger description into the file descriptor that defines the stall state - some or full, and the maximum stall time over a given window of time. E.g.: /* Signal when stall time exceeds 100ms of a 1s window */ char trigger[] = "full 100000 1000000" fd = open("/proc/pressure/memory") write(fd, trigger, sizeof(trigger)) while (poll() >= 0) { ... }; close(fd); When the monitored stall state is entered, psi adapts its aggregation frequency according to what the configured time window requires in order to emit event signals in a timely fashion. Once the stalling subsides, aggregation reverts back to normal. The trigger is associated with the open file descriptor. To stop monitoring, the user only needs to close the file descriptor and the trigger is discarded. Patches 1-6 prepare the psi code for polling support. Patch 7 implements the adaptive polling logic, the pressure growth detection optimized for short intervals, and hooks up write() and poll() on the pressure files. The patches were developed in collaboration with Johannes Weiner. This patch (of 7): The psi monitoring patches will need to determine the same states as record_times(). To avoid calculating them twice, maintain a state mask that can be consulted cheaply. Do this in a separate patch to keep the churn in the main feature patch at a minimum. This adds 4-byte state_mask member into psi_group_cpu struct which results in its first cacheline-aligned part becoming 52 bytes long. Add explicit values to enumeration element counters that affect psi_group_cpu struct size. Link: http://lkml.kernel.org/r/20190124211518.244221-4-surenb@google.comSigned-off-by:
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Baruch Siach authored
Commit 0139aa7b ("mm: rename _count, field of the struct page, to _refcount") left out a couple of references to the old field name. Fix that. Link: http://lkml.kernel.org/r/cedf87b02eb8a6b3eac57e8e91da53fb15c3c44c.1556537475.git.baruch@tkos.co.il Fixes: 0139aa7b ("mm: rename _count, field of the struct page, to _refcount") Signed-off-by:
Baruch Siach <baruch@tkos.co.il> Reviewed-by:
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Andrea Arcangeli authored
The RCU reader uses rcu_dereference() inside rcu_read_lock critical sections, so the writer shall use WRITE_ONCE. Just a cleanup, we still rely on gcc to emit atomic writes in other places. Link: http://lkml.kernel.org/r/20190325225636.11635-3-aarcange@redhat.comSigned-off-by:
Andrea Arcangeli <aarcange@redhat.com> Reviewed-by:
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Andrea Arcangeli authored
The task structure is freed while get_mem_cgroup_from_mm() holds rcu_read_lock() and dereferences mm->owner. get_mem_cgroup_from_mm() failing fork() ---- --- task = mm->owner mm->owner = NULL; free(task) if (task) *task; /* use after free */ The fix consists in freeing the task with RCU also in the fork failure case, exactly like it always happens for the regular exit(2) path. That is enough to make the rcu_read_lock hold in get_mem_cgroup_from_mm() (left side above) effective to avoid a use after free when dereferencing the task structure. An alternate possible fix would be to defer the delivery of the userfaultfd contexts to the monitor until after fork() is guaranteed to succeed. Such a change would require more changes because it would create a strict ordering dependency where the uffd methods would need to be called beyond the last potentially failing branch in order to be safe. This solution as opposed only adds the dependency to common code to set mm->owner to NULL and to free the task struct that was pointed by mm->owner with RCU, if fork ends up failing. The userfaultfd methods can still be called anywhere during the fork runtime and the monitor will keep discarding orphaned "mm" coming from failed forks in userland. This race condition couldn't trigger if CONFIG_MEMCG was set =n at build time. [aarcange@redhat.com: improve changelog, reduce #ifdefs per Michal] Link: http://lkml.kernel.org/r/20190429035752.4508-1-aarcange@redhat.com Link: http://lkml.kernel.org/r/20190325225636.11635-2-aarcange@redhat.com Fixes: 893e26e6 ("userfaultfd: non-cooperative: Add fork() event") Signed-off-by:zhong jiang <zhongjiang@huawei.com> Reported-by: syzbot+cbb52e396df3e565ab02@syzkaller.appspotmail.com Cc: Oleg Nesterov <oleg@redhat.com> Cc: Jann Horn <jannh@google.com> Cc: Hugh Dickins <hughd@google.com> Cc: Mike Rapoport <rppt@linux.vnet.ibm.com> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Peter Xu <peterx@redhat.com> Cc: Jason Gunthorpe <jgg@mellanox.com> Cc: "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com> Cc: Michal Hocko <mhocko@suse.com> Cc: zhong jiang <zhongjiang@huawei.com> Cc: syzbot+cbb52e396df3e565ab02@syzkaller.appspotmail.com Cc: <stable@vger.kernel.org> Signed-off-by:
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Andrew Morton authored
If the user downloads and applies patch-5.1.gz using patch(1), the x bit on kernel/gen_ikh_data.sh is not set. /bin/sh: 1: ./kernel/gen_ikh_data.sh: Permission denied Fix this by using CONFIG_SHELL. Signed-off-by:
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- 14 May, 2019 13 commits
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git://git.kernel.org/pub/scm/linux/kernel/git/lee/backlightLinus Torvalds authored
Pull backlight updates from Lee Jones: "Fix-ups: - Remove unused BACKLIGHT_LCD_SUPPORT symbol - Remove unused BACKLIGHT_CLASS_DEVICE dependencies - Add DT support to lm3630a_bl Bug Fixes: - Fix error path issues in lm3630a_bl" * tag 'backlight-next-5.2' of git://git.kernel.org/pub/scm/linux/kernel/git/lee/backlight: backlight: lm3630a: Add firmware node support dt-bindings: backlight: Add lm3630a bindings backlight: lm3630a: Return 0 on success in update_status functions video: lcd: Remove useless BACKLIGHT_CLASS_DEVICE dependencies video: backlight: Remove useless BACKLIGHT_LCD_SUPPORT kernel symbol
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git://git.kernel.org/pub/scm/linux/kernel/git/lee/mfdLinus Torvalds authored
Pull MFD updates from Lee Jones: "Core Framework: - Document (kerneldoc) core mfd_add_devices() API New Drivers: - Altera SOCFPGA System Manager - Maxim MAX77650/77651 PMIC - Maxim MAX77663 PMIC - ST Multi-Function eXpander (STMFX) New Device Support: - LEDs support in Intel Cherry Trail Whiskey Cove PMIC - RTC support in SAMSUNG Electronics S2MPA01 PMIC - SAM9X60 support in Atmel HLCDC (High-end LCD Controller) - USB X-Powers AXP 8xx PMICs - Integrated Sensor Hub (ISH) in ChromeOS EC - USB PD Logger in ChromeOS EC - AXP223 in X-Powers AXP series PMICs - Power Supply in X-Powers AXP 803 PMICs - Comet Lake in Intel Low Power Subsystem - Fingerprint MCU in ChromeOS EC - Touchpad MCU in ChromeOS EC - Move TI LM3532 support to LED New Functionality: - max77650, max77620: Add/extend DT support - max77620 power-off - syscon clocking - croc_ec host sleep event Fix-ups: - Trivial; Formatting, spelling, etc; Kconfig, sec-core, ab8500-debugfs - Remove unused functionality; rk808, da9063-* - SPDX conversion; da9063-*, atmel-*, - Adapt/add new register definitions; cs47l35-tables, cs47l90-tables, imx6q-iomuxc-gpr - Fix-up DT bindings; ti-lmu, cirrus,lochnagar - Simply obtaining driver data; ssbi, t7l66xb, tc6387xb, tc6393xb Bug Fixes: - Fix incorrect defined values; max77620, da9063 - Fix device initialisation; twl6040 - Reset device on init; intel-lpss - Fix build warnings when !OF; sun6i-prcm - Register OF match tables; tps65912-spi - Fix DMI matching; intel_quark_i2c_gpio" * tag 'mfd-next-5.2' of git://git.kernel.org/pub/scm/linux/kernel/git/lee/mfd: (65 commits) mfd: Use dev_get_drvdata() directly mfd: cros_ec: Instantiate properly CrOS Touchpad MCU device mfd: cros_ec: Instantiate properly CrOS FP MCU device mfd: cros_ec: Update the EC feature codes mfd: intel-lpss: Add Intel Comet Lake PCI IDs mfd: lochnagar: Add links to binding docs for sound and hwmon mfd: ab8500-debugfs: Fix a typo ("deubgfs") mfd: imx6sx: Add MQS register definition for iomuxc gpr dt-bindings: mfd: LMU: Fix lm3632 dt binding example mfd: intel_quark_i2c_gpio: Adjust IOT2000 matching mfd: da9063: Fix OTP control register names to match datasheets for DA9063/63L mfd: tps65912-spi: Add missing of table registration mfd: axp20x: Add USB power supply mfd cell to AXP803 mfd: sun6i-prcm: Fix build warning for non-OF configurations mfd: intel-lpss: Set the device in reset state when init platform/chrome: Add support for v1 of host sleep event mfd: cros_ec: Add host_sleep_event_v1 command mfd: cros_ec: Instantiate the CrOS USB PD logger driver mfd: cs47l90: Make DAC_AEC_CONTROL_2 readable mfd: cs47l35: Make DAC_AEC_CONTROL_2 readable ...
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git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pciLinus Torvalds authored
Pull PCI updates from Bjorn Helgaas: "Enumeration changes: - Add _HPX Type 3 settings support, which gives firmware more influence over device configuration (Alexandru Gagniuc) - Support fixed bus numbers from bridge Enhanced Allocation capabilities (Subbaraya Sundeep) - Add "external-facing" DT property to identify cases where we require IOMMU protection against untrusted devices (Jean-Philippe Brucker) - Enable PCIe services for host controller drivers that use managed host bridge alloc (Jean-Philippe Brucker) - Log PCIe port service messages with pci_dev, not the pcie_device (Frederick Lawler) - Convert pciehp from pciehp_debug module parameter to generic dynamic debug (Frederick Lawler) Peer-to-peer DMA: - Add whitelist of Root Complexes that support peer-to-peer DMA between Root Ports (Christian König) Native controller drivers: - Add PCI host bridge DMA ranges for bridges that can't DMA everywhere, e.g., iProc (Srinath Mannam) - Add Amazon Annapurna Labs PCIe host controller driver (Jonathan Chocron) - Fix Tegra MSI target allocation so DMA doesn't generate unwanted MSIs (Vidya Sagar) - Fix of_node reference leaks (Wen Yang) - Fix Hyper-V module unload & device removal issues (Dexuan Cui) - Cleanup R-Car driver (Marek Vasut) - Cleanup Keystone driver (Kishon Vijay Abraham I) - Cleanup i.MX6 driver (Andrey Smirnov) Significant bug fixes: - Reset Lenovo ThinkPad P50 GPU so nouveau works after reboot (Lyude Paul) - Fix Switchtec firmware update performance issue (Wesley Sheng) - Work around Pericom switch link retraining erratum (Stefan Mätje)" * tag 'pci-v5.2-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci: (141 commits) MAINTAINERS: Add Karthikeyan Mitran and Hou Zhiqiang for Mobiveil PCI PCI: pciehp: Remove pointless MY_NAME definition PCI: pciehp: Remove pointless PCIE_MODULE_NAME definition PCI: pciehp: Remove unused dbg/err/info/warn() wrappers PCI: pciehp: Log messages with pci_dev, not pcie_device PCI: pciehp: Replace pciehp_debug module param with dyndbg PCI: pciehp: Remove pciehp_debug uses PCI/AER: Log messages with pci_dev, not pcie_device PCI/DPC: Log messages with pci_dev, not pcie_device PCI/PME: Replace dev_printk(KERN_DEBUG) with dev_info() PCI/AER: Replace dev_printk(KERN_DEBUG) with dev_info() PCI: Replace dev_printk(KERN_DEBUG) with dev_info(), etc PCI: Replace printk(KERN_INFO) with pr_info(), etc PCI: Use dev_printk() when possible PCI: Cleanup setup-bus.c comments and whitespace PCI: imx6: Allow asynchronous probing PCI: dwc: Save root bus for driver remove hooks PCI: dwc: Use devm_pci_alloc_host_bridge() to simplify code PCI: dwc: Free MSI in dw_pcie_host_init() error path PCI: dwc: Free MSI IRQ page in dw_pcie_free_msi() ... -
Linus Torvalds authored
Merge misc updates from Andrew Morton: - a few misc things and hotfixes - ocfs2 - almost all of MM * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (139 commits) kernel/memremap.c: remove the unused device_private_entry_fault() export mm: delete find_get_entries_tag mm/huge_memory.c: make __thp_get_unmapped_area static mm/mprotect.c: fix compilation warning because of unused 'mm' variable mm/page-writeback: introduce tracepoint for wait_on_page_writeback() mm/vmscan: simplify trace_reclaim_flags and trace_shrink_flags mm/Kconfig: update "Memory Model" help text mm/vmscan.c: don't disable irq again when count pgrefill for memcg mm: memblock: make keeping memblock memory opt-in rather than opt-out hugetlbfs: always use address space in inode for resv_map pointer mm/z3fold.c: support page migration mm/z3fold.c: add structure for buddy handles mm/z3fold.c: improve compression by extending search mm/z3fold.c: introduce helper functions mm/page_alloc.c: remove unnecessary parameter in rmqueue_pcplist mm/hmm: add ARCH_HAS_HMM_MIRROR ARCH_HAS_HMM_DEVICE Kconfig mm/vmscan.c: simplify shrink_inactive_list() fs/sync.c: sync_file_range(2) may use WB_SYNC_ALL writeback xen/privcmd-buf.c: convert to use vm_map_pages_zero() xen/gntdev.c: convert to use vm_map_pages() ...
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Christoph Hellwig authored
This export has been entirely unused since it was added more than 1 1/2 years ago. Link: http://lkml.kernel.org/r/20190429115535.12793-1-hch@lst.deSigned-off-by:
Christoph Hellwig <hch@lst.de> Reviewed-by:
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Matthew Wilcox (Oracle) authored
I removed the only user of this and hadn't noticed it was now unused. Link: http://lkml.kernel.org/r/20190430152929.21813-1-willy@infradead.orgSigned-off-by:
Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by:
Ross Zwisler <zwisler@google.com> Signed-off-by:
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Bharath Vedartham authored
__thp_get_unmapped_area is only used in mm/huge_memory.c. Make it static. Tested by building and booting the kernel. Link: http://lkml.kernel.org/r/20190504102353.GA22525@bharath12345-Inspiron-5559Signed-off-by:
Bharath Vedartham <linux.bhar@gmail.com> Acked-by:
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Mike Rapoport authored
Since 0cbe3e26 ("mm: update ptep_modify_prot_start/commit to take vm_area_struct as arg") the only place that uses the local 'mm' variable in change_pte_range() is the call to set_pte_at(). Many architectures define set_pte_at() as macro that does not use the 'mm' parameter, which generates the following compilation warning: CC mm/mprotect.o mm/mprotect.c: In function 'change_pte_range': mm/mprotect.c:42:20: warning: unused variable 'mm' [-Wunused-variable] struct mm_struct *mm = vma->vm_mm; ^~ Fix it by passing vma->mm to set_pte_at() and dropping the local 'mm' variable in change_pte_range(). [liu.song.a23@gmail.com: fix missed conversions] Link: http://lkml.kernel.org/r/CAPhsuW6wcQgYLHNdBdw6m0YiR4RWsS4XzfpSKU7wBLLeOCTbpw@mail.gmail.comLink: http://lkml.kernel.org/r/1557305432-4940-1-git-send-email-rppt@linux.ibm.comSigned-off-by:
Mike Rapoport <rppt@linux.ibm.com> Reviewed-by:
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Yafang Shao authored
Recently there have been some hung tasks on our server due to wait_on_page_writeback(), and we want to know the details of this PG_writeback, i.e. this page is writing back to which device. But it is not so convenient to get the details. I think it would be better to introduce a tracepoint for diagnosing the writeback details. Link: http://lkml.kernel.org/r/1556274402-19018-1-git-send-email-laoar.shao@gmail.comSigned-off-by:
Yafang Shao <laoar.shao@gmail.com> Reviewed-by:
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Yafang Shao authored
trace_reclaim_flags and trace_shrink_flags are almost the same. We can simplify them to avoid redundant code. Link: http://lkml.kernel.org/r/1556169203-5858-1-git-send-email-laoar.shao@gmail.comSigned-off-by:
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Mike Rapoport authored
The help describing the memory model selection is outdated. It still says that SPARSEMEM is experimental and DISCONTIGMEM is a preferred over SPARSEMEM. Update the help text for the relevant options: * add a generic help for the "Memory Model" prompt * add description for FLATMEM * reduce the description of DISCONTIGMEM and add a deprecation note * prefer SPARSEMEM over DISCONTIGMEM Link: http://lkml.kernel.org/r/1556188531-20728-1-git-send-email-rppt@linux.ibm.comSigned-off-by:
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Yafang Shao authored
We can use __count_memcg_events() directly because this callsite is alreay protected by spin_lock_irq(). Link: http://lkml.kernel.org/r/1556093494-30798-1-git-send-email-laoar.shao@gmail.comSigned-off-by:
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Mike Rapoport authored
Most architectures do not need the memblock memory after the page allocator is initialized, but only few enable ARCH_DISCARD_MEMBLOCK in the arch Kconfig. Replacing ARCH_DISCARD_MEMBLOCK with ARCH_KEEP_MEMBLOCK and inverting the logic makes it clear which architectures actually use memblock after system initialization and skips the necessity to add ARCH_DISCARD_MEMBLOCK to the architectures that are still missing that option. Link: http://lkml.kernel.org/r/1556102150-32517-1-git-send-email-rppt@linux.ibm.comSigned-off-by:
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