1. 03 11月, 2020 4 次提交
  2. 26 10月, 2020 2 次提交
  3. 21 10月, 2020 1 次提交
  4. 19 10月, 2020 1 次提交
    • M
      mm/madvise: introduce process_madvise() syscall: an external memory hinting API · ecb8ac8b
      Minchan Kim 提交于
      There is usecase that System Management Software(SMS) want to give a
      memory hint like MADV_[COLD|PAGEEOUT] to other processes and in the
      case of Android, it is the ActivityManagerService.
      
      The information required to make the reclaim decision is not known to the
      app.  Instead, it is known to the centralized userspace
      daemon(ActivityManagerService), and that daemon must be able to initiate
      reclaim on its own without any app involvement.
      
      To solve the issue, this patch introduces a new syscall
      process_madvise(2).  It uses pidfd of an external process to give the
      hint.  It also supports vector address range because Android app has
      thousands of vmas due to zygote so it's totally waste of CPU and power if
      we should call the syscall one by one for each vma.(With testing 2000-vma
      syscall vs 1-vector syscall, it showed 15% performance improvement.  I
      think it would be bigger in real practice because the testing ran very
      cache friendly environment).
      
      Another potential use case for the vector range is to amortize the cost
      ofTLB shootdowns for multiple ranges when using MADV_DONTNEED; this could
      benefit users like TCP receive zerocopy and malloc implementations.  In
      future, we could find more usecases for other advises so let's make it
      happens as API since we introduce a new syscall at this moment.  With
      that, existing madvise(2) user could replace it with process_madvise(2)
      with their own pid if they want to have batch address ranges support
      feature.
      
      ince it could affect other process's address range, only privileged
      process(PTRACE_MODE_ATTACH_FSCREDS) or something else(e.g., being the same
      UID) gives it the right to ptrace the process could use it successfully.
      The flag argument is reserved for future use if we need to extend the API.
      
      I think supporting all hints madvise has/will supported/support to
      process_madvise is rather risky.  Because we are not sure all hints make
      sense from external process and implementation for the hint may rely on
      the caller being in the current context so it could be error-prone.  Thus,
      I just limited hints as MADV_[COLD|PAGEOUT] in this patch.
      
      If someone want to add other hints, we could hear the usecase and review
      it for each hint.  It's safer for maintenance rather than introducing a
      buggy syscall but hard to fix it later.
      
      So finally, the API is as follows,
      
            ssize_t process_madvise(int pidfd, const struct iovec *iovec,
                      unsigned long vlen, int advice, unsigned int flags);
      
          DESCRIPTION
            The process_madvise() system call is used to give advice or directions
            to the kernel about the address ranges from external process as well as
            local process. It provides the advice to address ranges of process
            described by iovec and vlen. The goal of such advice is to improve
            system or application performance.
      
            The pidfd selects the process referred to by the PID file descriptor
            specified in pidfd. (See pidofd_open(2) for further information)
      
            The pointer iovec points to an array of iovec structures, defined in
            <sys/uio.h> as:
      
              struct iovec {
                  void *iov_base;         /* starting address */
                  size_t iov_len;         /* number of bytes to be advised */
              };
      
            The iovec describes address ranges beginning at address(iov_base)
            and with size length of bytes(iov_len).
      
            The vlen represents the number of elements in iovec.
      
            The advice is indicated in the advice argument, which is one of the
            following at this moment if the target process specified by pidfd is
            external.
      
              MADV_COLD
              MADV_PAGEOUT
      
            Permission to provide a hint to external process is governed by a
            ptrace access mode PTRACE_MODE_ATTACH_FSCREDS check; see ptrace(2).
      
            The process_madvise supports every advice madvise(2) has if target
            process is in same thread group with calling process so user could
            use process_madvise(2) to extend existing madvise(2) to support
            vector address ranges.
      
          RETURN VALUE
            On success, process_madvise() returns the number of bytes advised.
            This return value may be less than the total number of requested
            bytes, if an error occurred. The caller should check return value
            to determine whether a partial advice occurred.
      
      FAQ:
      
      Q.1 - Why does any external entity have better knowledge?
      
      Quote from Sandeep
      
      "For Android, every application (including the special SystemServer)
      are forked from Zygote.  The reason of course is to share as many
      libraries and classes between the two as possible to benefit from the
      preloading during boot.
      
      After applications start, (almost) all of the APIs end up calling into
      this SystemServer process over IPC (binder) and back to the
      application.
      
      In a fully running system, the SystemServer monitors every single
      process periodically to calculate their PSS / RSS and also decides
      which process is "important" to the user for interactivity.
      
      So, because of how these processes start _and_ the fact that the
      SystemServer is looping to monitor each process, it does tend to *know*
      which address range of the application is not used / useful.
      
      Besides, we can never rely on applications to clean things up
      themselves.  We've had the "hey app1, the system is low on memory,
      please trim your memory usage down" notifications for a long time[1].
      They rely on applications honoring the broadcasts and very few do.
      
      So, if we want to avoid the inevitable killing of the application and
      restarting it, some way to be able to tell the OS about unimportant
      memory in these applications will be useful.
      
      - ssp
      
      Q.2 - How to guarantee the race(i.e., object validation) between when
      giving a hint from an external process and get the hint from the target
      process?
      
      process_madvise operates on the target process's address space as it
      exists at the instant that process_madvise is called.  If the space
      target process can run between the time the process_madvise process
      inspects the target process address space and the time that
      process_madvise is actually called, process_madvise may operate on
      memory regions that the calling process does not expect.  It's the
      responsibility of the process calling process_madvise to close this
      race condition.  For example, the calling process can suspend the
      target process with ptrace, SIGSTOP, or the freezer cgroup so that it
      doesn't have an opportunity to change its own address space before
      process_madvise is called.  Another option is to operate on memory
      regions that the caller knows a priori will be unchanged in the target
      process.  Yet another option is to accept the race for certain
      process_madvise calls after reasoning that mistargeting will do no
      harm.  The suggested API itself does not provide synchronization.  It
      also apply other APIs like move_pages, process_vm_write.
      
      The race isn't really a problem though.  Why is it so wrong to require
      that callers do their own synchronization in some manner?  Nobody
      objects to write(2) merely because it's possible for two processes to
      open the same file and clobber each other's writes --- instead, we tell
      people to use flock or something.  Think about mmap.  It never
      guarantees newly allocated address space is still valid when the user
      tries to access it because other threads could unmap the memory right
      before.  That's where we need synchronization by using other API or
      design from userside.  It shouldn't be part of API itself.  If someone
      needs more fine-grained synchronization rather than process level,
      there were two ideas suggested - cookie[2] and anon-fd[3].  Both are
      applicable via using last reserved argument of the API but I don't
      think it's necessary right now since we have already ways to prevent
      the race so don't want to add additional complexity with more
      fine-grained optimization model.
      
      To make the API extend, it reserved an unsigned long as last argument
      so we could support it in future if someone really needs it.
      
      Q.3 - Why doesn't ptrace work?
      
      Injecting an madvise in the target process using ptrace would not work
      for us because such injected madvise would have to be executed by the
      target process, which means that process would have to be runnable and
      that creates the risk of the abovementioned race and hinting a wrong
      VMA.  Furthermore, we want to act the hint in caller's context, not the
      callee's, because the callee is usually limited in cpuset/cgroups or
      even freezed state so they can't act by themselves quick enough, which
      causes more thrashing/kill.  It doesn't work if the target process are
      ptraced(e.g., strace, debugger, minidump) because a process can have at
      most one ptracer.
      
      [1] https://developer.android.com/topic/performance/memory"
      
      [2] process_getinfo for getting the cookie which is updated whenever
          vma of process address layout are changed - Daniel Colascione -
          https://lore.kernel.org/lkml/20190520035254.57579-1-minchan@kernel.org/T/#m7694416fd179b2066a2c62b5b139b14e3894e224
      
      [3] anonymous fd which is used for the object(i.e., address range)
          validation - Michal Hocko -
          https://lore.kernel.org/lkml/20200120112722.GY18451@dhcp22.suse.cz/
      
      [minchan@kernel.org: fix process_madvise build break for arm64]
        Link: http://lkml.kernel.org/r/20200303145756.GA219683@google.com
      [minchan@kernel.org: fix build error for mips of process_madvise]
        Link: http://lkml.kernel.org/r/20200508052517.GA197378@google.com
      [akpm@linux-foundation.org: fix patch ordering issue]
      [akpm@linux-foundation.org: fix arm64 whoops]
      [minchan@kernel.org: make process_madvise() vlen arg have type size_t, per Florian]
      [akpm@linux-foundation.org: fix i386 build]
      [sfr@canb.auug.org.au: fix syscall numbering]
        Link: https://lkml.kernel.org/r/20200905142639.49fc3f1a@canb.auug.org.au
      [sfr@canb.auug.org.au: madvise.c needs compat.h]
        Link: https://lkml.kernel.org/r/20200908204547.285646b4@canb.auug.org.au
      [minchan@kernel.org: fix mips build]
        Link: https://lkml.kernel.org/r/20200909173655.GC2435453@google.com
      [yuehaibing@huawei.com: remove duplicate header which is included twice]
        Link: https://lkml.kernel.org/r/20200915121550.30584-1-yuehaibing@huawei.com
      [minchan@kernel.org: do not use helper functions for process_madvise]
        Link: https://lkml.kernel.org/r/20200921175539.GB387368@google.com
      [akpm@linux-foundation.org: pidfd_get_pid() gained an argument]
      [sfr@canb.auug.org.au: fix up for "iov_iter: transparently handle compat iovecs in import_iovec"]
        Link: https://lkml.kernel.org/r/20200928212542.468e1fef@canb.auug.org.auSigned-off-by: NMinchan Kim <minchan@kernel.org>
      Signed-off-by: NYueHaibing <yuehaibing@huawei.com>
      Signed-off-by: NStephen Rothwell <sfr@canb.auug.org.au>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Reviewed-by: NSuren Baghdasaryan <surenb@google.com>
      Reviewed-by: NVlastimil Babka <vbabka@suse.cz>
      Acked-by: NDavid Rientjes <rientjes@google.com>
      Cc: Alexander Duyck <alexander.h.duyck@linux.intel.com>
      Cc: Brian Geffon <bgeffon@google.com>
      Cc: Christian Brauner <christian@brauner.io>
      Cc: Daniel Colascione <dancol@google.com>
      Cc: Jann Horn <jannh@google.com>
      Cc: Jens Axboe <axboe@kernel.dk>
      Cc: Joel Fernandes <joel@joelfernandes.org>
      Cc: Johannes Weiner <hannes@cmpxchg.org>
      Cc: John Dias <joaodias@google.com>
      Cc: Kirill Tkhai <ktkhai@virtuozzo.com>
      Cc: Michal Hocko <mhocko@suse.com>
      Cc: Oleksandr Natalenko <oleksandr@redhat.com>
      Cc: Sandeep Patil <sspatil@google.com>
      Cc: SeongJae Park <sj38.park@gmail.com>
      Cc: SeongJae Park <sjpark@amazon.de>
      Cc: Shakeel Butt <shakeelb@google.com>
      Cc: Sonny Rao <sonnyrao@google.com>
      Cc: Tim Murray <timmurray@google.com>
      Cc: Christian Brauner <christian.brauner@ubuntu.com>
      Cc: Florian Weimer <fw@deneb.enyo.de>
      Cc: <linux-man@vger.kernel.org>
      Link: http://lkml.kernel.org/r/20200302193630.68771-3-minchan@kernel.org
      Link: http://lkml.kernel.org/r/20200508183320.GA125527@google.com
      Link: http://lkml.kernel.org/r/20200622192900.22757-4-minchan@kernel.org
      Link: https://lkml.kernel.org/r/20200901000633.1920247-4-minchan@kernel.orgSigned-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      ecb8ac8b
  5. 18 10月, 2020 1 次提交
  6. 14 10月, 2020 3 次提交
    • M
      arch, drivers: replace for_each_membock() with for_each_mem_range() · b10d6bca
      Mike Rapoport 提交于
      There are several occurrences of the following pattern:
      
      	for_each_memblock(memory, reg) {
      		start = __pfn_to_phys(memblock_region_memory_base_pfn(reg);
      		end = __pfn_to_phys(memblock_region_memory_end_pfn(reg));
      
      		/* do something with start and end */
      	}
      
      Using for_each_mem_range() iterator is more appropriate in such cases and
      allows simpler and cleaner code.
      
      [akpm@linux-foundation.org: fix arch/arm/mm/pmsa-v7.c build]
      [rppt@linux.ibm.com: mips: fix cavium-octeon build caused by memblock refactoring]
        Link: http://lkml.kernel.org/r/20200827124549.GD167163@linux.ibm.comSigned-off-by: NMike Rapoport <rppt@linux.ibm.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Cc: Andy Lutomirski <luto@kernel.org>
      Cc: Baoquan He <bhe@redhat.com>
      Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Catalin Marinas <catalin.marinas@arm.com>
      Cc: Christoph Hellwig <hch@lst.de>
      Cc: Daniel Axtens <dja@axtens.net>
      Cc: Dave Hansen <dave.hansen@linux.intel.com>
      Cc: Emil Renner Berthing <kernel@esmil.dk>
      Cc: Hari Bathini <hbathini@linux.ibm.com>
      Cc: Ingo Molnar <mingo@kernel.org>
      Cc: Ingo Molnar <mingo@redhat.com>
      Cc: Jonathan Cameron <Jonathan.Cameron@huawei.com>
      Cc: Marek Szyprowski <m.szyprowski@samsung.com>
      Cc: Max Filippov <jcmvbkbc@gmail.com>
      Cc: Michael Ellerman <mpe@ellerman.id.au>
      Cc: Michal Simek <monstr@monstr.eu>
      Cc: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>
      Cc: Palmer Dabbelt <palmer@dabbelt.com>
      Cc: Paul Mackerras <paulus@samba.org>
      Cc: Paul Walmsley <paul.walmsley@sifive.com>
      Cc: Peter Zijlstra <peterz@infradead.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: Will Deacon <will@kernel.org>
      Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
      Link: https://lkml.kernel.org/r/20200818151634.14343-13-rppt@kernel.orgSigned-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      b10d6bca
    • M
      arch, mm: replace for_each_memblock() with for_each_mem_pfn_range() · c9118e6c
      Mike Rapoport 提交于
      There are several occurrences of the following pattern:
      
      	for_each_memblock(memory, reg) {
      		start_pfn = memblock_region_memory_base_pfn(reg);
      		end_pfn = memblock_region_memory_end_pfn(reg);
      
      		/* do something with start_pfn and end_pfn */
      	}
      
      Rather than iterate over all memblock.memory regions and each time query
      for their start and end PFNs, use for_each_mem_pfn_range() iterator to get
      simpler and clearer code.
      Signed-off-by: NMike Rapoport <rppt@linux.ibm.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Reviewed-by: NBaoquan He <bhe@redhat.com>
      Acked-by: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>	[.clang-format]
      Cc: Andy Lutomirski <luto@kernel.org>
      Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Catalin Marinas <catalin.marinas@arm.com>
      Cc: Christoph Hellwig <hch@lst.de>
      Cc: Daniel Axtens <dja@axtens.net>
      Cc: Dave Hansen <dave.hansen@linux.intel.com>
      Cc: Emil Renner Berthing <kernel@esmil.dk>
      Cc: Hari Bathini <hbathini@linux.ibm.com>
      Cc: Ingo Molnar <mingo@kernel.org>
      Cc: Ingo Molnar <mingo@redhat.com>
      Cc: Jonathan Cameron <Jonathan.Cameron@huawei.com>
      Cc: Marek Szyprowski <m.szyprowski@samsung.com>
      Cc: Max Filippov <jcmvbkbc@gmail.com>
      Cc: Michael Ellerman <mpe@ellerman.id.au>
      Cc: Michal Simek <monstr@monstr.eu>
      Cc: Palmer Dabbelt <palmer@dabbelt.com>
      Cc: Paul Mackerras <paulus@samba.org>
      Cc: Paul Walmsley <paul.walmsley@sifive.com>
      Cc: Peter Zijlstra <peterz@infradead.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: Will Deacon <will@kernel.org>
      Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
      Link: https://lkml.kernel.org/r/20200818151634.14343-12-rppt@kernel.orgSigned-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      c9118e6c
    • M
      memblock: make memblock_debug and related functionality private · 87c55870
      Mike Rapoport 提交于
      The only user of memblock_dbg() outside memblock was s390 setup code and
      it is converted to use pr_debug() instead.  This allows to stop exposing
      memblock_debug and memblock_dbg() to the rest of the kernel.
      
      [akpm@linux-foundation.org: make memblock_dbg() safer and neater]
      Signed-off-by: NMike Rapoport <rppt@linux.ibm.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Reviewed-by: NBaoquan He <bhe@redhat.com>
      Cc: Andy Lutomirski <luto@kernel.org>
      Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Catalin Marinas <catalin.marinas@arm.com>
      Cc: Christoph Hellwig <hch@lst.de>
      Cc: Daniel Axtens <dja@axtens.net>
      Cc: Dave Hansen <dave.hansen@linux.intel.com>
      Cc: Emil Renner Berthing <kernel@esmil.dk>
      Cc: Hari Bathini <hbathini@linux.ibm.com>
      Cc: Ingo Molnar <mingo@kernel.org>
      Cc: Ingo Molnar <mingo@redhat.com>
      Cc: Jonathan Cameron <Jonathan.Cameron@huawei.com>
      Cc: Marek Szyprowski <m.szyprowski@samsung.com>
      Cc: Max Filippov <jcmvbkbc@gmail.com>
      Cc: Michael Ellerman <mpe@ellerman.id.au>
      Cc: Michal Simek <monstr@monstr.eu>
      Cc: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>
      Cc: Palmer Dabbelt <palmer@dabbelt.com>
      Cc: Paul Mackerras <paulus@samba.org>
      Cc: Paul Walmsley <paul.walmsley@sifive.com>
      Cc: Peter Zijlstra <peterz@infradead.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: Will Deacon <will@kernel.org>
      Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
      Link: https://lkml.kernel.org/r/20200818151634.14343-10-rppt@kernel.orgSigned-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      87c55870
  7. 10 10月, 2020 3 次提交
  8. 09 10月, 2020 2 次提交
  9. 08 10月, 2020 5 次提交
  10. 06 10月, 2020 2 次提交
  11. 03 10月, 2020 3 次提交
  12. 02 10月, 2020 7 次提交
  13. 30 9月, 2020 6 次提交
    • V
      s390: remove orphaned function declarations · 402e9228
      Vasily Gorbik 提交于
      arch/s390/pci/pci_bus.h: zpci_bus_init - only declaration left after
      commit 05bc1be6 ("s390/pci: create zPCI bus")
      
      arch/s390/include/asm/gmap.h: gmap_pte_notify - only declaration left
      after commit 4be130a0 ("s390/mm: add shadow gmap support")
      
      arch/s390/include/asm/pgalloc.h: rcu_table_freelist_finish - only
      declaration left after commit 36409f63 ("[S390] use generic RCU
      page-table freeing code")
      
      arch/s390/include/asm/tlbflush.h: smp_ptlb_all - only declaration left
      after commit 5a79859a ("s390: remove 31 bit support")
      
      arch/s390/include/asm/vtimer.h: init_cpu_vtimer - only declaration left
      after commit b5f87f15 ("s390/idle: consolidate idle functions and
      definitions")
      
      arch/s390/include/asm/pci.h: zpci_debug_info - only declaration left
      after commit 386aa051 ("s390/pci: remove per device debug attribute")
      
      arch/s390/include/asm/vdso.h: vdso_alloc_boot_cpu - only declaration
      left after commit 4bff8cb5 ("s390: convert to GENERIC_VDSO")
      
      arch/s390/include/asm/smp.h: smp_vcpu_scheduled - only declaration left
      after commit 67626fad ("s390: enforce CONFIG_SMP")
      
      arch/s390/kernel/entry.h: restart_call_handler - only declaration left
      after commit 8b646bd7 ("[S390] rework smp code")
      
      arch/s390/kernel/entry.h: startup_init_nobss - only declaration left
      after commit 2e83e0eb ("s390: clean .bss before running uncompressed
      kernel")
      
      arch/s390/kernel/entry.h: s390_early_resume - only declaration left after
      commit 39421627 ("s390: remove broken hibernate / power management
      support")
      
      drivers/s390/char/raw3270.h: raw3270_request_alloc_bootmem - only
      declaration left after commit 33403dcf ("[S390] 3270 console:
      convert from bootmem to slab")
      
      drivers/s390/cio/device.h: ccw_device_schedule_sch_unregister - only
      declaration left after commit 37de53bb ("[S390] cio: introduce ccw
      device todos")
      
      drivers/s390/char/tape.h: tape_hotplug_event - has only declaration
      since recorded git history.
      
      drivers/s390/char/tape.h: tape_oper_handler - has only declaration since
      recorded git history.
      
      drivers/s390/char/tape.h: tape_noper_handler - has only declaration
      since recorded git history.
      
      drivers/s390/char/tape_std.h: tape_std_check_locate - only declaration
      left after commit 161beff8 ("s390/tape: remove tape block leftovers")
      
      drivers/s390/char/tape_std.h: tape_std_default_handler - has only
      declaration since recorded git history.
      
      drivers/s390/char/tape_std.h: tape_std_unexpect_uchk_handler - has only
      declaration since recorded git history.
      
      drivers/s390/char/tape_std.h: tape_std_irq - has only declaration since
      recorded git history.
      
      drivers/s390/char/tape_std.h: tape_std_error_recovery - has only
      declaration since recorded git history.
      
      drivers/s390/char/tape_std.h: tape_std_error_recovery_has_failed -
      has only declaration since recorded git history.
      
      drivers/s390/char/tape_std.h: tape_std_error_recovery_succeded - has
      only declaration since recorded git history.
      
      drivers/s390/char/tape_std.h: tape_std_error_recovery_do_retry - has
      only declaration since recorded git history.
      
      drivers/s390/char/tape_std.h: tape_std_error_recovery_read_opposite -
      has only declaration since recorded git history.
      
      drivers/s390/char/tape_std.h: tape_std_error_recovery_HWBUG - has only
      declaration since recorded git history.
      Reviewed-by: NSven Schnelle <svens@linux.ibm.com>
      Signed-off-by: NVasily Gorbik <gor@linux.ibm.com>
      402e9228
    • V
      s390/startup: add kaslr_offset to pgm check info print · 3ca8b855
      Vasily Gorbik 提交于
      startup pgm check handler is active since the very beginning of kernel
      code execution until uncompressed kernel sets up s390_base_pgm_handler.
      
      It is useful not just for the decompressor debugging itself, but also for
      early code of uncompressed kernel, in particular Kasan initialization. But
      since there is no stack trace or symbolic representation of failing psw
      address it is impossible to figure out faulty code location without
      knowing Kaslr kernel base. So, let's add it to the startup pgm check
      info printed as well.
      Reviewed-by: NSven Schnelle <svens@linux.ibm.com>
      Signed-off-by: NVasily Gorbik <gor@linux.ibm.com>
      3ca8b855
    • V
      s390/startup: correct "dfltcc" option parsing · 86cde618
      Vasily Gorbik 提交于
      Currently if just "dfltcc" is passed as a kernel command line option
      "val" going to be NULL, this leads to reading at address 0 in
      strcmp(val, "off")
      
      Fix that by making sure "val" is not NULL. This does not affect option
      handling logic.
      Reviewed-by: NSven Schnelle <svens@linux.ibm.com>
      Signed-off-by: NVasily Gorbik <gor@linux.ibm.com>
      86cde618
    • V
      s390/vdso: remove orphaned declarations · 3731ac57
      Vasily Gorbik 提交于
      Remove couple of declarations which are unused since commit 4bff8cb5
      ("s390: convert to GENERIC_VDSO").
      Acked-by: NSven Schnelle <svens@linux.ibm.com>
      Signed-off-by: NVasily Gorbik <gor@linux.ibm.com>
      3731ac57
    • V
      s390/cio: remove unused channel_subsystem_reinit · 54530ce6
      Vasily Gorbik 提交于
      Added with commit 77e844b9 ("s390/hibernate: add early resume
      function") unused since commit 39421627 ("s390: remove broken
      hibernate / power management support").
      Reviewed-by: NVineeth Vijayan <vneethv@linux.ibm.com>
      Signed-off-by: NVasily Gorbik <gor@linux.ibm.com>
      54530ce6
    • S
      s390: remove cad commandline option · ad3e6948
      Sven Schnelle 提交于
      remove the cad command line option as the instruction was never
      published and never used by userspace.
      Signed-off-by: NSven Schnelle <svens@linux.ibm.com>
      Reviewed-by: NVasily Gorbik <gor@linux.ibm.com>
      Acked-by: NChristian Borntraeger <borntraeger@de.ibm.com>
      Signed-off-by: NVasily Gorbik <gor@linux.ibm.com>
      ad3e6948