Commit Graph

98 Commits

Author SHA1 Message Date
Linus Torvalds 8f47d753d4 arm64 fixes for -rc1
- Fix lockdep false alarm on resume-from-cpuidle path
 
 - Fix memory leak in kexec_file
 
 - Fix module linker script to work with GDB
 
 - Fix error code when trying to use uprobes with AArch32 instructions
 
 - Fix late VHE enabling with 64k pages
 
 - Add missing ISBs after TLB invalidation
 
 - Fix seccomp when tracing syscall -1
 
 - Fix stacktrace return code at end of stack
 
 - Fix inconsistent whitespace for pointer return values
 
 - Fix compiler warnings when building with W=1
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Merge tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux

Pull arm64 fixes from Will Deacon:
 "The big one is a fix for the VHE enabling path during early boot,
  where the code enabling the MMU wasn't necessarily in the identity map
  of the new page-tables, resulting in a consistent crash with 64k
  pages. In fixing that, we noticed some missing barriers too, so we
  added those for the sake of architectural compliance.

  Other than that, just the usual merge window trickle. There'll be more
  to come, too.

  Summary:

   - Fix lockdep false alarm on resume-from-cpuidle path

   - Fix memory leak in kexec_file

   - Fix module linker script to work with GDB

   - Fix error code when trying to use uprobes with AArch32 instructions

   - Fix late VHE enabling with 64k pages

   - Add missing ISBs after TLB invalidation

   - Fix seccomp when tracing syscall -1

   - Fix stacktrace return code at end of stack

   - Fix inconsistent whitespace for pointer return values

   - Fix compiler warnings when building with W=1"

* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
  arm64: stacktrace: Report when we reach the end of the stack
  arm64: ptrace: Fix seccomp of traced syscall -1 (NO_SYSCALL)
  arm64: Add missing ISB after invalidating TLB in enter_vhe
  arm64: Add missing ISB after invalidating TLB in __primary_switch
  arm64: VHE: Enable EL2 MMU from the idmap
  KVM: arm64: make the hyp vector table entries local
  arm64/mm: Fixed some coding style issues
  arm64: uprobe: Return EOPNOTSUPP for AARCH32 instruction probing
  kexec: move machine_kexec_post_load() to public interface
  arm64 module: set plt* section addresses to 0x0
  arm64: kexec_file: fix memory leakage in create_dtb() when fdt_open_into() fails
  arm64: spectre: Prevent lockdep splat on v4 mitigation enable path
2021-02-26 10:19:03 -08:00
Pavel Tatashin 2596b6ae41 kexec: move machine_kexec_post_load() to public interface
The kernel test robot reports the following compiler warning:

  | arch/arm64/kernel/machine_kexec.c:62:5: warning: no previous prototype for
  | function 'machine_kexec_post_load' [-Wmissing-prototypes]
  |    int machine_kexec_post_load(struct kimage *kimage)

Fix it by moving the declaration of machine_kexec_post_load() from
kexec_internal.h to the public header instead.

Reported-by: kernel test robot <lkp@intel.com>
Link: https://lore.kernel.org/linux-arm-kernel/202102030727.gqTokACH-lkp@intel.com
Signed-off-by: Pavel Tatashin <pasha.tatashin@soleen.com>
Link: https://lore.kernel.org/r/20210219195142.13571-1-pasha.tatashin@soleen.com
Fixes: 4c3c31230c ("arm64: kexec: move relocation function setup")
Signed-off-by: Will Deacon <will@kernel.org>
2021-02-22 12:33:26 +00:00
Lakshmi Ramasubramanian f31e3386a4 ima: Free IMA measurement buffer after kexec syscall
IMA allocates kernel virtual memory to carry forward the measurement
list, from the current kernel to the next kernel on kexec system call,
in ima_add_kexec_buffer() function.  This buffer is not freed before
completing the kexec system call resulting in memory leak.

Add ima_buffer field in "struct kimage" to store the virtual address
of the buffer allocated for the IMA measurement list.
Free the memory allocated for the IMA measurement list in
kimage_file_post_load_cleanup() function.

Signed-off-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com>
Suggested-by: Tyler Hicks <tyhicks@linux.microsoft.com>
Reviewed-by: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Reviewed-by: Tyler Hicks <tyhicks@linux.microsoft.com>
Fixes: 7b8589cc29 ("ima: on soft reboot, save the measurement list")
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2021-02-10 15:49:38 -05:00
Hari Bathini f891f19736 kexec_file: Allow archs to handle special regions while locating memory hole
Some architectures may have special memory regions, within the given
memory range, which can't be used for the buffer in a kexec segment.
Implement weak arch_kexec_locate_mem_hole() definition which arch code
may override, to take care of special regions, while trying to locate
a memory hole.

Also, add the missing declarations for arch overridable functions and
and drop the __weak descriptors in the declarations to avoid non-weak
definitions from becoming weak.

Signed-off-by: Hari Bathini <hbathini@linux.ibm.com>
Tested-by: Pingfan Liu <piliu@redhat.com>
Reviewed-by: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Acked-by: Dave Young <dyoung@redhat.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/159602273603.575379.17665852963340380839.stgit@hbathini
2020-07-29 23:47:53 +10:00
Gustavo A. R. Silva 50b6951feb kexec: Replace zero-length array with flexible-array
There is a regular need in the kernel to provide a way to declare having a
dynamically sized set of trailing elements in a structure. Kernel code should
always use “flexible array members”[1] for these cases. The older style of
one-element or zero-length arrays should no longer be used[2].

[1] https://en.wikipedia.org/wiki/Flexible_array_member
[2] https://github.com/KSPP/linux/issues/21

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
2020-06-15 23:08:31 -05:00
Linus Torvalds aefcf2f4b5 Merge branch 'next-lockdown' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security
Pull kernel lockdown mode from James Morris:
 "This is the latest iteration of the kernel lockdown patchset, from
  Matthew Garrett, David Howells and others.

  From the original description:

    This patchset introduces an optional kernel lockdown feature,
    intended to strengthen the boundary between UID 0 and the kernel.
    When enabled, various pieces of kernel functionality are restricted.
    Applications that rely on low-level access to either hardware or the
    kernel may cease working as a result - therefore this should not be
    enabled without appropriate evaluation beforehand.

    The majority of mainstream distributions have been carrying variants
    of this patchset for many years now, so there's value in providing a
    doesn't meet every distribution requirement, but gets us much closer
    to not requiring external patches.

  There are two major changes since this was last proposed for mainline:

   - Separating lockdown from EFI secure boot. Background discussion is
     covered here: https://lwn.net/Articles/751061/

   -  Implementation as an LSM, with a default stackable lockdown LSM
      module. This allows the lockdown feature to be policy-driven,
      rather than encoding an implicit policy within the mechanism.

  The new locked_down LSM hook is provided to allow LSMs to make a
  policy decision around whether kernel functionality that would allow
  tampering with or examining the runtime state of the kernel should be
  permitted.

  The included lockdown LSM provides an implementation with a simple
  policy intended for general purpose use. This policy provides a coarse
  level of granularity, controllable via the kernel command line:

    lockdown={integrity|confidentiality}

  Enable the kernel lockdown feature. If set to integrity, kernel features
  that allow userland to modify the running kernel are disabled. If set to
  confidentiality, kernel features that allow userland to extract
  confidential information from the kernel are also disabled.

  This may also be controlled via /sys/kernel/security/lockdown and
  overriden by kernel configuration.

  New or existing LSMs may implement finer-grained controls of the
  lockdown features. Refer to the lockdown_reason documentation in
  include/linux/security.h for details.

  The lockdown feature has had signficant design feedback and review
  across many subsystems. This code has been in linux-next for some
  weeks, with a few fixes applied along the way.

  Stephen Rothwell noted that commit 9d1f8be5cf ("bpf: Restrict bpf
  when kernel lockdown is in confidentiality mode") is missing a
  Signed-off-by from its author. Matthew responded that he is providing
  this under category (c) of the DCO"

* 'next-lockdown' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (31 commits)
  kexec: Fix file verification on S390
  security: constify some arrays in lockdown LSM
  lockdown: Print current->comm in restriction messages
  efi: Restrict efivar_ssdt_load when the kernel is locked down
  tracefs: Restrict tracefs when the kernel is locked down
  debugfs: Restrict debugfs when the kernel is locked down
  kexec: Allow kexec_file() with appropriate IMA policy when locked down
  lockdown: Lock down perf when in confidentiality mode
  bpf: Restrict bpf when kernel lockdown is in confidentiality mode
  lockdown: Lock down tracing and perf kprobes when in confidentiality mode
  lockdown: Lock down /proc/kcore
  x86/mmiotrace: Lock down the testmmiotrace module
  lockdown: Lock down module params that specify hardware parameters (eg. ioport)
  lockdown: Lock down TIOCSSERIAL
  lockdown: Prohibit PCMCIA CIS storage when the kernel is locked down
  acpi: Disable ACPI table override if the kernel is locked down
  acpi: Ignore acpi_rsdp kernel param when the kernel has been locked down
  ACPI: Limit access to custom_method when the kernel is locked down
  x86/msr: Restrict MSR access when the kernel is locked down
  x86: Lock down IO port access when the kernel is locked down
  ...
2019-09-28 08:14:15 -07:00
Vasily Gorbik d5372c3913 kexec: restore arch_kexec_kernel_image_probe declaration
arch_kexec_kernel_image_probe function declaration has been removed by
commit 9ec4ecef0a ("kexec_file,x86,powerpc: factor out kexec_file_ops
functions").  Still this function is overridden by couple of architectures
and proper prototype declaration is therefore important, so bring it back.
This fixes the following sparse warning on s390:
arch/s390/kernel/machine_kexec_file.c:333:5: warning: symbol
'arch_kexec_kernel_image_probe' was not declared.  Should it be static?

Link: http://lkml.kernel.org/r/patch.git-ff1c9045ebdc.your-ad-here.call-01564402297-ext-5690@work.hours
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Acked-by: Dave Young <dyoung@redhat.com>
Reviewed-by: Bhupesh Sharma <bhsharma@redhat.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: AKASHI Takahiro <takahiro.akashi@linaro.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-09-25 17:51:40 -07:00
Sven Schnelle 5f71d97720 kexec_elf: remove parsing of section headers
We're not using them, so we can drop the parsing.

Signed-off-by: Sven Schnelle <svens@stackframe.org>
Reviewed-by: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Signed-off-by: Helge Deller <deller@gmx.de>
2019-09-06 23:58:43 +02:00
Sven Schnelle 175fca3bf9 kexec: add KEXEC_ELF
Right now powerpc provides an implementation to read elf files
with the kexec_file_load() syscall. Make that available as a public
kexec interface so it can be re-used on other architectures.

Signed-off-by: Sven Schnelle <svens@stackframe.org>
Reviewed-by: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Signed-off-by: Helge Deller <deller@gmx.de>
2019-09-06 23:58:43 +02:00
Jiri Bohac 99d5cadfde kexec_file: split KEXEC_VERIFY_SIG into KEXEC_SIG and KEXEC_SIG_FORCE
This is a preparatory patch for kexec_file_load() lockdown.  A locked down
kernel needs to prevent unsigned kernel images from being loaded with
kexec_file_load().  Currently, the only way to force the signature
verification is compiling with KEXEC_VERIFY_SIG.  This prevents loading
usigned images even when the kernel is not locked down at runtime.

This patch splits KEXEC_VERIFY_SIG into KEXEC_SIG and KEXEC_SIG_FORCE.
Analogous to the MODULE_SIG and MODULE_SIG_FORCE for modules, KEXEC_SIG
turns on the signature verification but allows unsigned images to be
loaded.  KEXEC_SIG_FORCE disallows images without a valid signature.

Signed-off-by: Jiri Bohac <jbohac@suse.cz>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Matthew Garrett <mjg59@google.com>
cc: kexec@lists.infradead.org
Signed-off-by: James Morris <jmorris@namei.org>
2019-08-19 21:54:15 -07:00
Linus Torvalds 312a466155 Merge branch 'x86-cleanups-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 cleanups from Ingo Molnar:
 "Misc cleanups"

* 'x86-cleanups-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/kprobes: Remove trampoline_handler() prototype
  x86/kernel: Fix more -Wmissing-prototypes warnings
  x86: Fix various typos in comments
  x86/headers: Fix -Wmissing-prototypes warning
  x86/process: Avoid unnecessary NULL check in get_wchan()
  x86/traps: Complete prototype declarations
  x86/mce: Fix -Wmissing-prototypes warnings
  x86/gart: Rewrite early_gart_iommu_check() comment
2018-12-26 17:03:51 -08:00
AKASHI Takahiro 735c2f90e3 powerpc, kexec_file: factor out memblock-based arch_kexec_walk_mem()
Memblock list is another source for usable system memory layout.
So move powerpc's arch_kexec_walk_mem() to common code so that other
memblock-based architectures, particularly arm64, can also utilise it.
A moved function is now renamed to kexec_walk_memblock() and integrated
into kexec_locate_mem_hole(), which will now be usable for all
architectures with no need for overriding arch_kexec_walk_mem().

With this change, arch_kexec_walk_mem() need no longer be a weak function,
and was now renamed to kexec_walk_resources().

Since powerpc doesn't support kdump in its kexec_file_load(), the current
kexec_walk_memblock() won't work for kdump either in this form, this will
be fixed in the next patch.

Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Acked-by: Dave Young <dyoung@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Baoquan He <bhe@redhat.com>
Acked-by: James Morse <james.morse@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-12-06 14:38:50 +00:00
AKASHI Takahiro b6664ba42f s390, kexec_file: drop arch_kexec_mem_walk()
Since s390 already knows where to locate buffers, calling
arch_kexec_mem_walk() has no sense. So we can just drop it as kbuf->mem
indicates this while all other architectures sets it to 0 initially.

This change is a preparatory work for the next patch, where all the
variant memory walks, either on system resource or memblock, will be
put in one common place so that it will satisfy all the architectures'
need.

Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Reviewed-by: Philipp Rudo <prudo@linux.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Baoquan He <bhe@redhat.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-12-06 14:38:49 +00:00
AKASHI Takahiro 92a98a2b9f kexec_file: make kexec_image_post_load_cleanup_default() global
Change this function from static to global so that arm64 can implement
its own arch_kimage_file_post_load_cleanup() later using
kexec_image_post_load_cleanup_default().

Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Acked-by: Dave Young <dyoung@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Baoquan He <bhe@redhat.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-12-06 14:38:49 +00:00
Yi Wang 89f579ce99 x86/headers: Fix -Wmissing-prototypes warning
When building the kernel with W=1 we get a lot of -Wmissing-prototypes
warnings, which are trivial in nature and easy to fix - and which may
mask some real future bugs if the prototypes get out of sync with
the function definition.

This patch fixes most of -Wmissing-prototypes warnings which
are in the root directory of arch/x86/kernel, not including
the subdirectories.

These are the warnings fixed in this patch:

  arch/x86/kernel/signal.c:865:17: warning: no previous prototype for ‘sys32_x32_rt_sigreturn’ [-Wmissing-prototypes]
  arch/x86/kernel/signal_compat.c:164:6: warning: no previous prototype for ‘sigaction_compat_abi’ [-Wmissing-prototypes]
  arch/x86/kernel/traps.c:625:46: warning: no previous prototype for ‘sync_regs’ [-Wmissing-prototypes]
  arch/x86/kernel/traps.c:640:24: warning: no previous prototype for ‘fixup_bad_iret’ [-Wmissing-prototypes]
  arch/x86/kernel/traps.c:929:13: warning: no previous prototype for ‘trap_init’ [-Wmissing-prototypes]
  arch/x86/kernel/irq.c:270:28: warning: no previous prototype for ‘smp_x86_platform_ipi’ [-Wmissing-prototypes]
  arch/x86/kernel/irq.c:301:16: warning: no previous prototype for ‘smp_kvm_posted_intr_ipi’ [-Wmissing-prototypes]
  arch/x86/kernel/irq.c:314:16: warning: no previous prototype for ‘smp_kvm_posted_intr_wakeup_ipi’ [-Wmissing-prototypes]
  arch/x86/kernel/irq.c:328:16: warning: no previous prototype for ‘smp_kvm_posted_intr_nested_ipi’ [-Wmissing-prototypes]
  arch/x86/kernel/irq_work.c:16:28: warning: no previous prototype for ‘smp_irq_work_interrupt’ [-Wmissing-prototypes]
  arch/x86/kernel/irqinit.c:79:13: warning: no previous prototype for ‘init_IRQ’ [-Wmissing-prototypes]
  arch/x86/kernel/quirks.c:672:13: warning: no previous prototype for ‘early_platform_quirks’ [-Wmissing-prototypes]
  arch/x86/kernel/tsc.c:1499:15: warning: no previous prototype for ‘calibrate_delay_is_known’ [-Wmissing-prototypes]
  arch/x86/kernel/process.c:653:13: warning: no previous prototype for ‘arch_post_acpi_subsys_init’ [-Wmissing-prototypes]
  arch/x86/kernel/process.c:717:15: warning: no previous prototype for ‘arch_randomize_brk’ [-Wmissing-prototypes]
  arch/x86/kernel/process.c:784:6: warning: no previous prototype for ‘do_arch_prctl_common’ [-Wmissing-prototypes]
  arch/x86/kernel/reboot.c:869:6: warning: no previous prototype for ‘nmi_panic_self_stop’ [-Wmissing-prototypes]
  arch/x86/kernel/smp.c:176:27: warning: no previous prototype for ‘smp_reboot_interrupt’ [-Wmissing-prototypes]
  arch/x86/kernel/smp.c:260:28: warning: no previous prototype for ‘smp_reschedule_interrupt’ [-Wmissing-prototypes]
  arch/x86/kernel/smp.c:281:28: warning: no previous prototype for ‘smp_call_function_interrupt’ [-Wmissing-prototypes]
  arch/x86/kernel/smp.c:291:28: warning: no previous prototype for ‘smp_call_function_single_interrupt’ [-Wmissing-prototypes]
  arch/x86/kernel/ftrace.c:840:6: warning: no previous prototype for ‘arch_ftrace_update_trampoline’ [-Wmissing-prototypes]
  arch/x86/kernel/ftrace.c:934:7: warning: no previous prototype for ‘arch_ftrace_trampoline_func’ [-Wmissing-prototypes]
  arch/x86/kernel/ftrace.c:946:6: warning: no previous prototype for ‘arch_ftrace_trampoline_free’ [-Wmissing-prototypes]
  arch/x86/kernel/crash.c:114:6: warning: no previous prototype for ‘crash_smp_send_stop’ [-Wmissing-prototypes]
  arch/x86/kernel/crash.c:351:5: warning: no previous prototype for ‘crash_setup_memmap_entries’ [-Wmissing-prototypes]
  arch/x86/kernel/crash.c:424:5: warning: no previous prototype for ‘crash_load_segments’ [-Wmissing-prototypes]
  arch/x86/kernel/machine_kexec_64.c:372:7: warning: no previous prototype for ‘arch_kexec_kernel_image_load’ [-Wmissing-prototypes]
  arch/x86/kernel/paravirt-spinlocks.c:12:16: warning: no previous prototype for ‘__native_queued_spin_unlock’ [-Wmissing-prototypes]
  arch/x86/kernel/paravirt-spinlocks.c:18:6: warning: no previous prototype for ‘pv_is_native_spin_unlock’ [-Wmissing-prototypes]
  arch/x86/kernel/paravirt-spinlocks.c:24:16: warning: no previous prototype for ‘__native_vcpu_is_preempted’ [-Wmissing-prototypes]
  arch/x86/kernel/paravirt-spinlocks.c:30:6: warning: no previous prototype for ‘pv_is_native_vcpu_is_preempted’ [-Wmissing-prototypes]
  arch/x86/kernel/kvm.c:258:1: warning: no previous prototype for ‘do_async_page_fault’ [-Wmissing-prototypes]
  arch/x86/kernel/jailhouse.c:200:6: warning: no previous prototype for ‘jailhouse_paravirt’ [-Wmissing-prototypes]
  arch/x86/kernel/check.c:91:13: warning: no previous prototype for ‘setup_bios_corruption_check’ [-Wmissing-prototypes]
  arch/x86/kernel/check.c:139:6: warning: no previous prototype for ‘check_for_bios_corruption’ [-Wmissing-prototypes]
  arch/x86/kernel/devicetree.c:32:13: warning: no previous prototype for ‘early_init_dt_scan_chosen_arch’ [-Wmissing-prototypes]
  arch/x86/kernel/devicetree.c:42:13: warning: no previous prototype for ‘add_dtb’ [-Wmissing-prototypes]
  arch/x86/kernel/devicetree.c:108:6: warning: no previous prototype for ‘x86_of_pci_init’ [-Wmissing-prototypes]
  arch/x86/kernel/devicetree.c:314:13: warning: no previous prototype for ‘x86_dtb_init’ [-Wmissing-prototypes]
  arch/x86/kernel/tracepoint.c:16:5: warning: no previous prototype for ‘trace_pagefault_reg’ [-Wmissing-prototypes]
  arch/x86/kernel/tracepoint.c:22:6: warning: no previous prototype for ‘trace_pagefault_unreg’ [-Wmissing-prototypes]
  arch/x86/kernel/head64.c:113:22: warning: no previous prototype for ‘__startup_64’ [-Wmissing-prototypes]
  arch/x86/kernel/head64.c:262:15: warning: no previous prototype for ‘__startup_secondary_64’ [-Wmissing-prototypes]
  arch/x86/kernel/head64.c:350:12: warning: no previous prototype for ‘early_make_pgtable’ [-Wmissing-prototypes]

[ mingo: rewrote the changelog, fixed build errors. ]

Signed-off-by: Yi Wang <wang.yi59@zte.com.cn>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: akataria@vmware.com
Cc: akpm@linux-foundation.org
Cc: andy.shevchenko@gmail.com
Cc: anton@enomsg.org
Cc: ard.biesheuvel@linaro.org
Cc: bhe@redhat.com
Cc: bhelgaas@google.com
Cc: bp@alien8.de
Cc: ccross@android.com
Cc: devicetree@vger.kernel.org
Cc: douly.fnst@cn.fujitsu.com
Cc: dwmw@amazon.co.uk
Cc: dyoung@redhat.com
Cc: ebiederm@xmission.com
Cc: frank.rowand@sony.com
Cc: frowand.list@gmail.com
Cc: ivan.gorinov@intel.com
Cc: jailhouse-dev@googlegroups.com
Cc: jan.kiszka@siemens.com
Cc: jgross@suse.com
Cc: jroedel@suse.de
Cc: keescook@chromium.org
Cc: kexec@lists.infradead.org
Cc: konrad.wilk@oracle.com
Cc: kvm@vger.kernel.org
Cc: linux-efi@vger.kernel.org
Cc: linux-pci@vger.kernel.org
Cc: luto@kernel.org
Cc: m.mizuma@jp.fujitsu.com
Cc: namit@vmware.com
Cc: oleg@redhat.com
Cc: pasha.tatashin@oracle.com
Cc: pbonzini@redhat.com
Cc: prarit@redhat.com
Cc: pravin.shedge4linux@gmail.com
Cc: rajvi.jingar@intel.com
Cc: rkrcmar@redhat.com
Cc: robh+dt@kernel.org
Cc: robh@kernel.org
Cc: rostedt@goodmis.org
Cc: takahiro.akashi@linaro.org
Cc: thomas.lendacky@amd.com
Cc: tony.luck@intel.com
Cc: up2wing@gmail.com
Cc: virtualization@lists.linux-foundation.org
Cc: zhe.he@windriver.com
Cc: zhong.weidong@zte.com.cn
Link: http://lkml.kernel.org/r/1542852249-19820-1-git-send-email-wang.yi59@zte.com.cn
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-11-23 07:59:59 +01:00
Philipp Rudo 3be3f61d25 kernel/kexec_file.c: allow archs to set purgatory load address
For s390 new kernels are loaded to fixed addresses in memory before they
are booted.  With the current code this is a problem as it assumes the
kernel will be loaded to an 'arbitrary' address.  In particular,
kexec_locate_mem_hole searches for a large enough memory region and sets
the load address (kexec_bufer->mem) to it.

Luckily there is a simple workaround for this problem.  By returning 1
in arch_kexec_walk_mem, kexec_locate_mem_hole is turned off.  This
allows the architecture to set kbuf->mem by hand.  While the trick works
fine for the kernel it does not for the purgatory as here the
architectures don't have access to its kexec_buffer.

Give architectures access to the purgatories kexec_buffer by changing
kexec_load_purgatory to take a pointer to it.  With this change
architectures have access to the buffer and can edit it as they need.

A nice side effect of this change is that we can get rid of the
purgatory_info->purgatory_load_address field.  As now the information
stored there can directly be accessed from kbuf->mem.

Link: http://lkml.kernel.org/r/20180321112751.22196-11-prudo@linux.vnet.ibm.com
Signed-off-by: Philipp Rudo <prudo@linux.vnet.ibm.com>
Reviewed-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Acked-by: Dave Young <dyoung@redhat.com>
Cc: AKASHI Takahiro <takahiro.akashi@linaro.org>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-13 17:10:28 -07:00
Philipp Rudo 8aec395b84 kernel/kexec_file.c: use read-only sections in arch_kexec_apply_relocations*
When the relocations are applied to the purgatory only the section the
relocations are applied to is writable.  The other sections, i.e.  the
symtab and .rel/.rela, are in read-only kexec_purgatory.  Highlight this
by marking the corresponding variables as 'const'.

While at it also change the signatures of arch_kexec_apply_relocations* to
take section pointers instead of just the index of the relocation section.
This removes the second lookup and sanity check of the sections in arch
code.

Link: http://lkml.kernel.org/r/20180321112751.22196-6-prudo@linux.vnet.ibm.com
Signed-off-by: Philipp Rudo <prudo@linux.vnet.ibm.com>
Acked-by: Dave Young <dyoung@redhat.com>
Cc: AKASHI Takahiro <takahiro.akashi@linaro.org>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-13 17:10:28 -07:00
Philipp Rudo 65c225d328 kernel/kexec_file.c: make purgatory_info->ehdr const
The kexec_purgatory buffer is read-only.  Thus all pointers into
kexec_purgatory are read-only, too.  Point this out by explicitly
marking purgatory_info->ehdr as 'const' and update the comments in
purgatory_info.

Link: http://lkml.kernel.org/r/20180321112751.22196-4-prudo@linux.vnet.ibm.com
Signed-off-by: Philipp Rudo <prudo@linux.vnet.ibm.com>
Acked-by: Dave Young <dyoung@redhat.com>
Cc: AKASHI Takahiro <takahiro.akashi@linaro.org>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-13 17:10:28 -07:00
Philipp Rudo ee6ebeda8d include/linux/kexec.h: silence compile warnings
Patch series "kexec_file: Clean up purgatory load", v2.

Following the discussion with Dave and AKASHI, here are the common code
patches extracted from my recent patch set (Add kexec_file_load support
to s390) [1].  The patches were extracted to allow upstream integration
together with AKASHI's common code patches before the arch code gets
adjusted to the new base.

The reason for this series is to prepare common code for adding
kexec_file_load to s390 as well as cleaning up the mis-use of the
sh_offset field during purgatory load.  In detail this series contains:

Patch #1&2: Minor cleanups/fixes.

Patch #3-9: Clean up the purgatory load/relocation code.  Especially
remove the mis-use of the purgatory_info->sechdrs->sh_offset field,
currently holding a pointer into either kexec_purgatory (ro) or
purgatory_buf (rw) depending on the section.  With these patches the
section address will be calculated verbosely and sh_offset will contain
the offset of the section in the stripped purgatory binary
(purgatory_buf).

Patch #10: Allows architectures to set the purgatory load address.  This
patch is important for s390 as the kernel and purgatory have to be
loaded to fixed addresses.  In current code this is impossible as the
purgatory load is opaque to the architecture.

Patch #11: Moves x86 purgatories sha implementation to common lib/
directory to allow reuse in other architectures.

This patch (of 11)

When building the kernel with CONFIG_KEXEC_FILE enabled gcc prints a
compile warning multiple times.

  In file included from <path>/linux/init/initramfs.c:526:0:
  <path>/include/linux/kexec.h:120:9: warning: `struct kimage' declared inside parameter list [enabled by default]
           unsigned long cmdline_len);
           ^

This is because the typedefs for kexec_file_load uses struct kimage
before it is declared.  Fix this by simply forward declaring struct
kimage.

Link: http://lkml.kernel.org/r/20180321112751.22196-2-prudo@linux.vnet.ibm.com
Signed-off-by: Philipp Rudo <prudo@linux.vnet.ibm.com>
Acked-by: Dave Young <dyoung@redhat.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: AKASHI Takahiro <takahiro.akashi@linaro.org>
Cc: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-13 17:10:27 -07:00
AKASHI Takahiro babac4a84a kexec_file, x86: move re-factored code to generic side
In the previous patches, commonly-used routines, exclude_mem_range() and
prepare_elf64_headers(), were carved out.  Now place them in kexec
common code.  A prefix "crash_" is given to each of their names to avoid
possible name collisions.

Link: http://lkml.kernel.org/r/20180306102303.9063-8-takahiro.akashi@linaro.org
Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Acked-by: Dave Young <dyoung@redhat.com>
Tested-by: Dave Young <dyoung@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Baoquan He <bhe@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-13 17:10:27 -07:00
AKASHI Takahiro 9ec4ecef0a kexec_file,x86,powerpc: factor out kexec_file_ops functions
As arch_kexec_kernel_image_{probe,load}(),
arch_kimage_file_post_load_cleanup() and arch_kexec_kernel_verify_sig()
are almost duplicated among architectures, they can be commonalized with
an architecture-defined kexec_file_ops array.  So let's factor them out.

Link: http://lkml.kernel.org/r/20180306102303.9063-3-takahiro.akashi@linaro.org
Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Acked-by: Dave Young <dyoung@redhat.com>
Tested-by: Dave Young <dyoung@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-13 17:10:27 -07:00
Dominik Brodowski 1bec510a9e kexec: move sys_kexec_load() prototype to syscalls.h
As the syscall function should only be called from the system call table
but not from elsewhere in the kernel, move the prototype for
sys_kexec_load() to include/syscall.h.

Cc: Eric Biederman <ebiederm@xmission.com>
Cc: kexec@lists.infradead.org
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
2018-04-02 20:16:15 +02:00
Tom Lendacky 1d2e733b13 resource: Provide resource struct in resource walk callback
In preperation for a new function that will need additional resource
information during the resource walk, update the resource walk callback to
pass the resource structure.  Since the current callback start and end
arguments are pulled from the resource structure, the callback functions
can obtain them from the resource structure directly.

Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Borislav Petkov <bp@suse.de>
Tested-by: Borislav Petkov <bp@suse.de>
Cc: kvm@vger.kernel.org
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: linuxppc-dev@lists.ozlabs.org
Link: https://lkml.kernel.org/r/20171020143059.3291-10-brijesh.singh@amd.com
2017-11-07 15:35:57 +01:00
Greg Kroah-Hartman b24413180f License cleanup: add SPDX GPL-2.0 license identifier to files with no license
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.

By default all files without license information are under the default
license of the kernel, which is GPL version 2.

Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier.  The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.

How this work was done:

Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
 - file had no licensing information it it.
 - file was a */uapi/* one with no licensing information in it,
 - file was a */uapi/* one with existing licensing information,

Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.

The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne.  Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.

The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed.  Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.

Criteria used to select files for SPDX license identifier tagging was:
 - Files considered eligible had to be source code files.
 - Make and config files were included as candidates if they contained >5
   lines of source
 - File already had some variant of a license header in it (even if <5
   lines).

All documentation files were explicitly excluded.

The following heuristics were used to determine which SPDX license
identifiers to apply.

 - when both scanners couldn't find any license traces, file was
   considered to have no license information in it, and the top level
   COPYING file license applied.

   For non */uapi/* files that summary was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0                                              11139

   and resulted in the first patch in this series.

   If that file was a */uapi/* path one, it was "GPL-2.0 WITH
   Linux-syscall-note" otherwise it was "GPL-2.0".  Results of that was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0 WITH Linux-syscall-note                        930

   and resulted in the second patch in this series.

 - if a file had some form of licensing information in it, and was one
   of the */uapi/* ones, it was denoted with the Linux-syscall-note if
   any GPL family license was found in the file or had no licensing in
   it (per prior point).  Results summary:

   SPDX license identifier                            # files
   ---------------------------------------------------|------
   GPL-2.0 WITH Linux-syscall-note                       270
   GPL-2.0+ WITH Linux-syscall-note                      169
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause)    21
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause)    17
   LGPL-2.1+ WITH Linux-syscall-note                      15
   GPL-1.0+ WITH Linux-syscall-note                       14
   ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause)    5
   LGPL-2.0+ WITH Linux-syscall-note                       4
   LGPL-2.1 WITH Linux-syscall-note                        3
   ((GPL-2.0 WITH Linux-syscall-note) OR MIT)              3
   ((GPL-2.0 WITH Linux-syscall-note) AND MIT)             1

   and that resulted in the third patch in this series.

 - when the two scanners agreed on the detected license(s), that became
   the concluded license(s).

 - when there was disagreement between the two scanners (one detected a
   license but the other didn't, or they both detected different
   licenses) a manual inspection of the file occurred.

 - In most cases a manual inspection of the information in the file
   resulted in a clear resolution of the license that should apply (and
   which scanner probably needed to revisit its heuristics).

 - When it was not immediately clear, the license identifier was
   confirmed with lawyers working with the Linux Foundation.

 - If there was any question as to the appropriate license identifier,
   the file was flagged for further research and to be revisited later
   in time.

In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.

Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights.  The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.

Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.

In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.

Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
 - a full scancode scan run, collecting the matched texts, detected
   license ids and scores
 - reviewing anything where there was a license detected (about 500+
   files) to ensure that the applied SPDX license was correct
 - reviewing anything where there was no detection but the patch license
   was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
   SPDX license was correct

This produced a worksheet with 20 files needing minor correction.  This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.

These .csv files were then reviewed by Greg.  Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected.  This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.)  Finally Greg ran the script using the .csv files to
generate the patches.

Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-02 11:10:55 +01:00
Tom Lendacky bba4ed011a x86/mm, kexec: Allow kexec to be used with SME
Provide support so that kexec can be used to boot a kernel when SME is
enabled.

Support is needed to allocate pages for kexec without encryption.  This
is needed in order to be able to reboot in the kernel in the same manner
as originally booted.

Additionally, when shutting down all of the CPUs we need to be sure to
flush the caches and then halt. This is needed when booting from a state
where SME was not active into a state where SME is active (or vice-versa).
Without these steps, it is possible for cache lines to exist for the same
physical location but tagged both with and without the encryption bit. This
can cause random memory corruption when caches are flushed depending on
which cacheline is written last.

Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bp@suse.de>
Cc: <kexec@lists.infradead.org>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brijesh Singh <brijesh.singh@amd.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Larry Woodman <lwoodman@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Toshimitsu Kani <toshi.kani@hpe.com>
Cc: kasan-dev@googlegroups.com
Cc: kvm@vger.kernel.org
Cc: linux-arch@vger.kernel.org
Cc: linux-doc@vger.kernel.org
Cc: linux-efi@vger.kernel.org
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/b95ff075db3e7cd545313f2fb609a49619a09625.1500319216.git.thomas.lendacky@amd.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-07-18 11:38:04 +02:00
Xunlei Pang 1229384f5b kdump: protect vmcoreinfo data under the crash memory
Currently vmcoreinfo data is updated at boot time subsys_initcall(), it
has the risk of being modified by some wrong code during system is
running.

As a result, vmcore dumped may contain the wrong vmcoreinfo.  Later on,
when using "crash", "makedumpfile", etc utility to parse this vmcore, we
probably will get "Segmentation fault" or other unexpected errors.

E.g.  1) wrong code overwrites vmcoreinfo_data; 2) further crashes the
system; 3) trigger kdump, then we obviously will fail to recognize the
crash context correctly due to the corrupted vmcoreinfo.

Now except for vmcoreinfo, all the crash data is well
protected(including the cpu note which is fully updated in the crash
path, thus its correctness is guaranteed).  Given that vmcoreinfo data
is a large chunk prepared for kdump, we better protect it as well.

To solve this, we relocate and copy vmcoreinfo_data to the crash memory
when kdump is loading via kexec syscalls.  Because the whole crash
memory will be protected by existing arch_kexec_protect_crashkres()
mechanism, we naturally protect vmcoreinfo_data from write(even read)
access under kernel direct mapping after kdump is loaded.

Since kdump is usually loaded at the very early stage after boot, we can
trust the correctness of the vmcoreinfo data copied.

On the other hand, we still need to operate the vmcoreinfo safe copy
when crash happens to generate vmcoreinfo_note again, we rely on vmap()
to map out a new kernel virtual address and update to use this new one
instead in the following crash_save_vmcoreinfo().

BTW, we do not touch vmcoreinfo_note, because it will be fully updated
using the protected vmcoreinfo_data after crash which is surely correct
just like the cpu crash note.

Link: http://lkml.kernel.org/r/1493281021-20737-3-git-send-email-xlpang@redhat.com
Signed-off-by: Xunlei Pang <xlpang@redhat.com>
Tested-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Dave Young <dyoung@redhat.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Hari Bathini <hbathini@linux.vnet.ibm.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-07-12 16:26:00 -07:00
Michael Holzheu cd0ae1d395 s390/crash: Remove unused KEXEC_NOTE_BYTES
After commmit 692f66f26a ("crash: move crashkernel parsing and vmcore
related code under CONFIG_CRASH_CORE") the KEXEC_NOTE_BYTES macro is not
used anymore and for s390 we create the ELF header in the new kernel
anyway. Therefore remove the macro.

Reported-by: Xunlei Pang <xpang@redhat.com>
Reviewed-by: Mikhail Zaslonko <zaslonko@linux.vnet.ibm.com>
Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2017-07-05 07:35:29 +02:00
Hari Bathini 692f66f26a crash: move crashkernel parsing and vmcore related code under CONFIG_CRASH_CORE
Patch series "kexec/fadump: remove dependency with CONFIG_KEXEC and
reuse crashkernel parameter for fadump", v4.

Traditionally, kdump is used to save vmcore in case of a crash.  Some
architectures like powerpc can save vmcore using architecture specific
support instead of kexec/kdump mechanism.  Such architecture specific
support also needs to reserve memory, to be used by dump capture kernel.
crashkernel parameter can be a reused, for memory reservation, by such
architecture specific infrastructure.

This patchset removes dependency with CONFIG_KEXEC for crashkernel
parameter and vmcoreinfo related code as it can be reused without kexec
support.  Also, crashkernel parameter is reused instead of
fadump_reserve_mem to reserve memory for fadump.

The first patch moves crashkernel parameter parsing and vmcoreinfo
related code under CONFIG_CRASH_CORE instead of CONFIG_KEXEC_CORE.  The
second patch reuses the definitions of append_elf_note() & final_note()
functions under CONFIG_CRASH_CORE in IA64 arch code.  The third patch
removes dependency on CONFIG_KEXEC for firmware-assisted dump (fadump)
in powerpc.  The next patch reuses crashkernel parameter for reserving
memory for fadump, instead of the fadump_reserve_mem parameter.  This
has the advantage of using all syntaxes crashkernel parameter supports,
for fadump as well.  The last patch updates fadump kernel documentation
about use of crashkernel parameter.

This patch (of 5):

Traditionally, kdump is used to save vmcore in case of a crash.  Some
architectures like powerpc can save vmcore using architecture specific
support instead of kexec/kdump mechanism.  Such architecture specific
support also needs to reserve memory, to be used by dump capture kernel.
crashkernel parameter can be a reused, for memory reservation, by such
architecture specific infrastructure.

But currently, code related to vmcoreinfo and parsing of crashkernel
parameter is built under CONFIG_KEXEC_CORE.  This patch introduces
CONFIG_CRASH_CORE and moves the above mentioned code under this config,
allowing code reuse without dependency on CONFIG_KEXEC.  There is no
functional change with this patch.

Link: http://lkml.kernel.org/r/149035338104.6881.4550894432615189948.stgit@hbathini.in.ibm.com
Signed-off-by: Hari Bathini <hbathini@linux.vnet.ibm.com>
Acked-by: Dave Young <dyoung@redhat.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-05-08 17:15:11 -07:00
Linus Torvalds de399813b5 powerpc updates for 4.10
Highlights include:
 
  - Support for the kexec_file_load() syscall, which is a prereq for secure and
    trusted boot.
 
  - Prevent kernel execution of userspace on P9 Radix (similar to SMEP/PXN).
 
  - Sort the exception tables at build time, to save time at boot, and store
    them as relative offsets to save space in the kernel image & memory.
 
  - Allow building the kernel with thin archives, which should allow us to build
    an allyesconfig once some other fixes land.
 
  - Build fixes to allow us to correctly rebuild when changing the kernel endian
    from big to little or vice versa.
 
  - Plumbing so that we can avoid doing a full mm TLB flush on P9 Radix.
 
  - Initial stack protector support (-fstack-protector).
 
  - Support for dumping the radix (aka. Linux) and hash page tables via debugfs.
 
  - Fix an oops in cxl coredump generation when cxl_get_fd() is used.
 
  - Freescale updates from Scott: "Highlights include 8xx hugepage support,
    qbman fixes/cleanup, device tree updates, and some misc cleanup."
 
  - Many and varied fixes and minor enhancements as always.
 
 Thanks to:
   Alexey Kardashevskiy, Andrew Donnellan, Aneesh Kumar K.V, Anshuman Khandual,
   Anton Blanchard, Balbir Singh, Bartlomiej Zolnierkiewicz, Christophe Jaillet,
   Christophe Leroy, Denis Kirjanov, Elimar Riesebieter, Frederic Barrat,
   Gautham R. Shenoy, Geliang Tang, Geoff Levand, Jack Miller, Johan Hovold,
   Lars-Peter Clausen, Libin, Madhavan Srinivasan, Michael Neuling, Nathan
   Fontenot, Naveen N. Rao, Nicholas Piggin, Pan Xinhui, Peter Senna Tschudin,
   Rashmica Gupta, Rui Teng, Russell Currey, Scott Wood, Simon Guo, Suraj
   Jitindar Singh, Thiago Jung Bauermann, Tobias Klauser, Vaibhav Jain.
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Merge tag 'powerpc-4.10-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc updates from Michael Ellerman:
 "Highlights include:

   - Support for the kexec_file_load() syscall, which is a prereq for
     secure and trusted boot.

   - Prevent kernel execution of userspace on P9 Radix (similar to
     SMEP/PXN).

   - Sort the exception tables at build time, to save time at boot, and
     store them as relative offsets to save space in the kernel image &
     memory.

   - Allow building the kernel with thin archives, which should allow us
     to build an allyesconfig once some other fixes land.

   - Build fixes to allow us to correctly rebuild when changing the
     kernel endian from big to little or vice versa.

   - Plumbing so that we can avoid doing a full mm TLB flush on P9
     Radix.

   - Initial stack protector support (-fstack-protector).

   - Support for dumping the radix (aka. Linux) and hash page tables via
     debugfs.

   - Fix an oops in cxl coredump generation when cxl_get_fd() is used.

   - Freescale updates from Scott: "Highlights include 8xx hugepage
     support, qbman fixes/cleanup, device tree updates, and some misc
     cleanup."

   - Many and varied fixes and minor enhancements as always.

  Thanks to:
    Alexey Kardashevskiy, Andrew Donnellan, Aneesh Kumar K.V, Anshuman
    Khandual, Anton Blanchard, Balbir Singh, Bartlomiej Zolnierkiewicz,
    Christophe Jaillet, Christophe Leroy, Denis Kirjanov, Elimar
    Riesebieter, Frederic Barrat, Gautham R. Shenoy, Geliang Tang, Geoff
    Levand, Jack Miller, Johan Hovold, Lars-Peter Clausen, Libin,
    Madhavan Srinivasan, Michael Neuling, Nathan Fontenot, Naveen N.
    Rao, Nicholas Piggin, Pan Xinhui, Peter Senna Tschudin, Rashmica
    Gupta, Rui Teng, Russell Currey, Scott Wood, Simon Guo, Suraj
    Jitindar Singh, Thiago Jung Bauermann, Tobias Klauser, Vaibhav Jain"

[ And thanks to Michael, who took time off from a new baby to get this
  pull request done.   - Linus ]

* tag 'powerpc-4.10-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (174 commits)
  powerpc/fsl/dts: add FMan node for t1042d4rdb
  powerpc/fsl/dts: add sg_2500_aqr105_phy4 alias on t1024rdb
  powerpc/fsl/dts: add QMan and BMan nodes on t1024
  powerpc/fsl/dts: add QMan and BMan nodes on t1023
  soc/fsl/qman: test: use DEFINE_SPINLOCK()
  powerpc/fsl-lbc: use DEFINE_SPINLOCK()
  powerpc/8xx: Implement support of hugepages
  powerpc: get hugetlbpage handling more generic
  powerpc: port 64 bits pgtable_cache to 32 bits
  powerpc/boot: Request no dynamic linker for boot wrapper
  soc/fsl/bman: Use resource_size instead of computation
  soc/fsl/qe: use builtin_platform_driver
  powerpc/fsl_pmc: use builtin_platform_driver
  powerpc/83xx/suspend: use builtin_platform_driver
  powerpc/ftrace: Fix the comments for ftrace_modify_code
  powerpc/perf: macros for power9 format encoding
  powerpc/perf: power9 raw event format encoding
  powerpc/perf: update attribute_group data structure
  powerpc/perf: factor out the event format field
  powerpc/mm/iommu, vfio/spapr: Put pages on VFIO container shutdown
  ...
2016-12-16 09:26:42 -08:00
Baoquan He 69f5838479 Revert "kdump, vmcoreinfo: report memory sections virtual addresses"
This reverts commit 0549a3c02e ("kdump, vmcoreinfo: report memory
sections virtual addresses").

Commit 0549a3c02e tells the userspace utility makedumpfile the
randomized base address of these memmory sections when mm kaslr is
enabled.  However the following patch "kexec: export the value of
phys_base instead of symbol address" makes makedumpfile not need these
addresses any more.

Besides we should use VMCOREINFO_NUMBER to export the value of the
variable so that we can use the existing number_table mechanism of
Makedumpfile to fetch it.  So revert it now.  If needed we can add it
later.

http://lists.infradead.org/pipermail/kexec/2016-October/017540.html
Link: http://lkml.kernel.org/r/1478568596-30060-1-git-send-email-bhe@redhat.com
Signed-off-by: Baoquan He <bhe@redhat.com>
Cc: Thomas Garnier <thgarnie@google.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Xunlei Pang <xlpang@redhat.com>
Cc: HATAYAMA Daisuke <d.hatayama@jp.fujitsu.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Eugene Surovegin <surovegin@google.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: AKASHI Takahiro <takahiro.akashi@linaro.org>
Cc: Atsushi Kumagai <ats-kumagai@wm.jp.nec.com>
Cc: Dave Anderson <anderson@redhat.com>
Cc: Pratyush Anand <panand@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-12-14 16:04:07 -08:00
Thiago Jung Bauermann e2e806f9e4 kexec_file: Factor out kexec_locate_mem_hole from kexec_add_buffer.
kexec_locate_mem_hole will be used by the PowerPC kexec_file_load
implementation to find free memory for the purgatory stack.

Signed-off-by: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Acked-by: Dave Young <dyoung@redhat.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-11-30 23:15:01 +11:00
Thiago Jung Bauermann ec2b9bfaac kexec_file: Change kexec_add_buffer to take kexec_buf as argument.
This is done to simplify the kexec_add_buffer argument list.
Adapt all callers to set up a kexec_buf to pass to kexec_add_buffer.

In addition, change the type of kexec_buf.buffer from char * to void *.
There is no particular reason for it to be a char *, and the change
allows us to get rid of 3 existing casts to char * in the code.

Signed-off-by: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Acked-by: Dave Young <dyoung@redhat.com>
Acked-by: Balbir Singh <bsingharora@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-11-30 23:14:59 +11:00
Thiago Jung Bauermann 60fe3910bb kexec_file: Allow arch-specific memory walking for kexec_add_buffer
Allow architectures to specify a different memory walking function for
kexec_add_buffer. x86 uses iomem to track reserved memory ranges, but
PowerPC uses the memblock subsystem.

Signed-off-by: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Acked-by: Dave Young <dyoung@redhat.com>
Acked-by: Balbir Singh <bsingharora@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-11-30 23:14:57 +11:00
Thomas Garnier 0549a3c02e kdump, vmcoreinfo: report memory sections virtual addresses
KASLR memory randomization can randomize the base of the physical memory
mapping (PAGE_OFFSET), vmalloc (VMALLOC_START) and vmemmap
(VMEMMAP_START).  Adding these variables on VMCOREINFO so tools can easily
identify the base of each memory section.

Link: http://lkml.kernel.org/r/1471531632-23003-1-git-send-email-thgarnie@google.com
Signed-off-by: Thomas Garnier <thgarnie@google.com>
Acked-by: Baoquan He <bhe@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Xunlei Pang <xlpang@redhat.com>
Cc: HATAYAMA Daisuke <d.hatayama@jp.fujitsu.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Eugene Surovegin <surovegin@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-10-11 15:06:33 -07:00
Petr Tesarik 21db79e8bb kexec: add a kexec_crash_loaded() function
Provide a wrapper function to be used by kernel code to check whether a
crash kernel is loaded.  It returns the same value that can be seen in
/sys/kernel/kexec_crash_loaded by userspace programs.

I'm exporting the function, because it will be used by Xen, and it is
possible to compile Xen modules separately to enable the use of PV
drivers with unmodified bare-metal kernels.

Link: http://lkml.kernel.org/r/20160713121955.14969.69080.stgit@hananiah.suse.cz
Signed-off-by: Petr Tesarik <ptesarik@suse.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: David Vrabel <david.vrabel@citrix.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-08-02 19:35:30 -04:00
Russell King 43546d8669 kexec: allow architectures to override boot mapping
kexec physical addresses are the boot-time view of the system.  For
certain ARM systems (such as Keystone 2), the boot view of the system
does not match the kernel's view of the system: the boot view uses a
special alias in the lower 4GB of the physical address space.

To cater for these kinds of setups, we need to translate between the
boot view physical addresses and the normal kernel view physical
addresses.  This patch extracts the current transation points into
linux/kexec.h, and allows an architecture to override the functions.

Due to the translations required, we unfortunately end up with six
translation functions, which are reduced down to four that the
architecture can override.

[akpm@linux-foundation.org: kexec.h needs asm/io.h for phys_to_virt()]
Link: http://lkml.kernel.org/r/E1b8koP-0004HZ-Vf@rmk-PC.armlinux.org.uk
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Cc: Keerthy <j-keerthy@ti.com>
Cc: Pratyush Anand <panand@redhat.com>
Cc: Vitaly Andrianov <vitalya@ti.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Simon Horman <horms@verge.net.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-08-02 19:35:27 -04:00
Russell King dae28018f5 kdump: arrange for paddr_vmcoreinfo_note() to return phys_addr_t
On PAE systems (eg, ARM LPAE) the vmcore note may be located above 4GB
physical on 32-bit architectures, so we need a wider type than "unsigned
long" here.  Arrange for paddr_vmcoreinfo_note() to return a
phys_addr_t, thereby allowing it to be located above 4GB.

This makes no difference for kexec-tools, as they already assume a
64-bit type when reading from this file.

Link: http://lkml.kernel.org/r/E1b8koK-0004HS-K9@rmk-PC.armlinux.org.uk
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Reviewed-by: Pratyush Anand <panand@redhat.com>
Acked-by: Baoquan He <bhe@redhat.com>
Cc: Keerthy <j-keerthy@ti.com>
Cc: Vitaly Andrianov <vitalya@ti.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Simon Horman <horms@verge.net.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-08-02 19:35:27 -04:00
Russell King dc5cccacf4 kexec: don't invoke OOM-killer for control page allocation
If we are unable to find a suitable page when allocating the control
page, do not invoke the OOM-killer: killing processes probably isn't
going to help.

Link: http://lkml.kernel.org/r/E1b8ko9-0004HG-R5@rmk-PC.armlinux.org.uk
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Reviewed-by: Pratyush Anand <panand@redhat.com>
Acked-by: Baoquan He <bhe@redhat.com>
Cc: Keerthy <j-keerthy@ti.com>
Cc: Vitaly Andrianov <vitalya@ti.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Simon Horman <horms@verge.net.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-08-02 19:35:26 -04:00
Xunlei Pang 7a0058ec78 s390/kexec: consolidate crash_map/unmap_reserved_pages() and arch_kexec_protect(unprotect)_crashkres()
Commit 3f625002581b ("kexec: introduce a protection mechanism for the
crashkernel reserved memory") is a similar mechanism for protecting the
crash kernel reserved memory to previous crash_map/unmap_reserved_pages()
implementation, the new one is more generic in name and cleaner in code
(besides, some arch may not be allowed to unmap the pgtable).

Therefore, this patch consolidates them, and uses the new
arch_kexec_protect(unprotect)_crashkres() to replace former
crash_map/unmap_reserved_pages() which by now has been only used by
S390.

The consolidation work needs the crash memory to be mapped initially,
this is done in machine_kdump_pm_init() which is after
reserve_crashkernel().  Once kdump kernel is loaded, the new
arch_kexec_protect_crashkres() implemented for S390 will actually
unmap the pgtable like before.

Signed-off-by: Xunlei Pang <xlpang@redhat.com>
Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Acked-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Minfei Huang <mhuang@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Baoquan He <bhe@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-05-23 17:04:14 -07:00
Xunlei Pang 9b492cf580 kexec: introduce a protection mechanism for the crashkernel reserved memory
For the cases that some kernel (module) path stamps the crash reserved
memory(already mapped by the kernel) where has been loaded the second
kernel data, the kdump kernel will probably fail to boot when panic
happens (or even not happens) leaving the culprit at large, this is
unacceptable.

The patch introduces a mechanism for detecting such cases:

1) After each crash kexec loading, it simply marks the reserved memory
   regions readonly since we no longer access it after that.  When someone
   stamps the region, the first kernel will panic and trigger the kdump.
   The weak arch_kexec_protect_crashkres() is introduced to do the actual
   protection.

2) To allow multiple loading, once 1) was done we also need to remark
   the reserved memory to readwrite each time a system call related to
   kdump is made.  The weak arch_kexec_unprotect_crashkres() is introduced
   to do the actual protection.

The architecture can make its specific implementation by overriding
arch_kexec_protect_crashkres() and arch_kexec_unprotect_crashkres().

Signed-off-by: Xunlei Pang <xlpang@redhat.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Minfei Huang <mhuang@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Baoquan He <bhe@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-05-23 17:04:14 -07:00
Xunlei Pang 978e30c9b4 kexec: move some memembers and definitions within the scope of CONFIG_KEXEC_FILE
Move the stuff currently only used by the kexec file code within
CONFIG_KEXEC_FILE (and CONFIG_KEXEC_VERIFY_SIG).

Also move internal "struct kexec_sha_region" and "struct kexec_buf" into
"kexec_internal.h".

Signed-off-by: Xunlei Pang <xlpang@redhat.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Dave Young <dyoung@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-20 17:09:18 -08:00
Hidehiro Kawai 7bbee5ca38 kexec: Fix race between panic() and crash_kexec()
Currently, panic() and crash_kexec() can be called at the same time.
For example (x86 case):

CPU 0:
  oops_end()
    crash_kexec()
      mutex_trylock() // acquired
        nmi_shootdown_cpus() // stop other CPUs

CPU 1:
  panic()
    crash_kexec()
      mutex_trylock() // failed to acquire
    smp_send_stop() // stop other CPUs
    infinite loop

If CPU 1 calls smp_send_stop() before nmi_shootdown_cpus(), kdump
fails.

In another case:

CPU 0:
  oops_end()
    crash_kexec()
      mutex_trylock() // acquired
        <NMI>
        io_check_error()
          panic()
            crash_kexec()
              mutex_trylock() // failed to acquire
            infinite loop

Clearly, this is an undesirable result.

To fix this problem, this patch changes crash_kexec() to exclude others
by using the panic_cpu atomic.

Signed-off-by: Hidehiro Kawai <hidehiro.kawai.ez@hitachi.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Baoquan He <bhe@redhat.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: HATAYAMA Daisuke <d.hatayama@jp.fujitsu.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: kexec@lists.infradead.org
Cc: linux-doc@vger.kernel.org
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Minfei Huang <mnfhuang@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Seth Jennings <sjenning@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: x86-ml <x86@kernel.org>
Link: http://lkml.kernel.org/r/20151210014630.25437.94161.stgit@softrs
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-12-19 11:07:01 +01:00
Dave Young 2965faa5e0 kexec: split kexec_load syscall from kexec core code
There are two kexec load syscalls, kexec_load another and kexec_file_load.
 kexec_file_load has been splited as kernel/kexec_file.c.  In this patch I
split kexec_load syscall code to kernel/kexec.c.

And add a new kconfig option KEXEC_CORE, so we can disable kexec_load and
use kexec_file_load only, or vice verse.

The original requirement is from Ted Ts'o, he want kexec kernel signature
being checked with CONFIG_KEXEC_VERIFY_SIG enabled.  But kexec-tools use
kexec_load syscall can bypass the checking.

Vivek Goyal proposed to create a common kconfig option so user can compile
in only one syscall for loading kexec kernel.  KEXEC/KEXEC_FILE selects
KEXEC_CORE so that old config files still work.

Because there's general code need CONFIG_KEXEC_CORE, so I updated all the
architecture Kconfig with a new option KEXEC_CORE, and let KEXEC selects
KEXEC_CORE in arch Kconfig.  Also updated general kernel code with to
kexec_load syscall.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Dave Young <dyoung@redhat.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Petr Tesarik <ptesarik@suse.cz>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: Josh Boyer <jwboyer@fedoraproject.org>
Cc: David Howells <dhowells@redhat.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-10 13:29:01 -07:00
Dave Young a43cac0d9d kexec: split kexec_file syscall code to kexec_file.c
Split kexec_file syscall related code to another file kernel/kexec_file.c
so that the #ifdef CONFIG_KEXEC_FILE in kexec.c can be dropped.

Sharing variables and functions are moved to kernel/kexec_internal.h per
suggestion from Vivek and Petr.

[akpm@linux-foundation.org: fix bisectability]
[akpm@linux-foundation.org: declare the various arch_kexec functions]
[akpm@linux-foundation.org: fix build]
Signed-off-by: Dave Young <dyoung@redhat.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Petr Tesarik <ptesarik@suse.cz>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: Josh Boyer <jwboyer@fedoraproject.org>
Cc: David Howells <dhowells@redhat.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-10 13:29:01 -07:00
Vitaly Kuznetsov 2b94ed2458 kexec: define kexec_in_progress in !CONFIG_KEXEC case
If some piece of code wants to check kexec_in_progress it has to be put
in #ifdef CONFIG_KEXEC block to not break the build in !CONFIG_KEXEC
case. Overcome this limitation by defining kexec_in_progress to false.

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-08-04 22:25:28 -07:00
Martin Schwidefsky 7e01b5acd8 kexec: allocate the kexec control page with KEXEC_CONTROL_MEMORY_GFP
Introduce KEXEC_CONTROL_MEMORY_GFP to allow the architecture code
to override the gfp flags of the allocation for the kexec control
page. The loop in kimage_alloc_normal_control_pages allocates pages
with GFP_KERNEL until a page is found that happens to have an
address smaller than the KEXEC_CONTROL_MEMORY_LIMIT. On systems
with a large memory size but a small KEXEC_CONTROL_MEMORY_LIMIT
the loop will keep allocating memory until the oom killer steps in.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-04-23 16:52:01 +02:00
Geoff Levand b28c2ee868 kexec: add IND_FLAGS macro
Add a new kexec preprocessor macro IND_FLAGS, which is the bitwise OR of
all the possible kexec IND_ kimage_entry indirection flags.  Having this
macro allows for simplified code in the prosessing of the kexec
kimage_entry items.  Also, remove the local powerpc definition and use the
generic one.

Signed-off-by: Geoff Levand <geoff@infradead.org>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Maximilian Attems <max@stro.at>
Cc: Michal Marek <mmarek@suse.cz>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Paul Bolle <pebolle@tiscali.nl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-02-17 14:34:51 -08:00
Geoff Levand cf2df6396b kexec: add bit definitions for kimage entry flags
Define new kexec preprocessor macros IND_*_BIT that define the bit
position of the kimage entry flags.  Change the existing IND_* flag macros
to be defined as bit shifts of the corresponding IND_*_BIT macros.  Also
wrap all C language code in kexec.h with #if !defined(__ASSEMBLY__) so
assembly files can include kexec.h to get the IND_* and IND_*_BIT macros.

Some CPU instruction sets have tests for bit position which are convenient
in implementing routines that operate on the kimage entry list.  The
addition of these bit position macros in a common location will avoid
duplicate definitions and the chance that changes to the IND_* flags will
not be propagated to assembly files.

Signed-off-by: Geoff Levand <geoff@infradead.org>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Maximilian Attems <max@stro.at>
Cc: Michal Marek <mmarek@suse.cz>
Cc: Paul Bolle <pebolle@tiscali.nl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-02-17 14:34:51 -08:00
Baoquan He 73d7e3eac0 kexec: remove never used member destination in kimage
struct kimage has a member destination which is used to store the real
destination address of each page when load segment from user space buffer
to kernel.  But we never retrieve the value stored in kimage->destination,
so this member variable in kimage and its assignment operation are
redundent code.

I guess for_each_kimage_entry just does the work that kimage->destination
is expected to do.

So in this patch just make a cleanup to remove it.

Signed-off-by: Baoquan He <bhe@redhat.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-02-17 14:34:51 -08:00
Baoquan He 669280a152 kexec: take the segment adding out of locate_mem_hole functions
In locate_mem_hole functions, a memory hole is located and added as
kexec_segment.  But from the name of locate_mem_hole, it should only take
responsibility of searching a available memory hole to contain data of a
specified size.

So in this patch add a new field 'mem' into kexec_buf, then take that
kexec segment adding code out of locate_mem_hole_top_down and
locate_mem_hole_bottom_up.  This make clear of the functionality of
locate_mem_hole just like it declars to do.  And by this
locate_mem_hole_callback chould be used later if anyone want to locate a
memory hole for other use.

Meanwhile Vivek suggested opening code function __kexec_add_segment(),
that way we have to retreive ksegment pointer once and it is easy to read.
 So just do it in this patch and remove __kexec_add_segment() since no one
use it anymore.

Signed-off-by: Baoquan He <bhe@redhat.com>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-10-14 02:18:21 +02:00