Commit graph

71 commits

Author SHA1 Message Date
Lianbo Jiang
a3e1c3bb24 x86/crash: Correct the address boundary of function parameters
Let's carefully handle the boundary of the function parameter to make
sure that the arguments passed doesn't exceed the address range.

Signed-off-by: Lianbo Jiang <lijiang@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Dave Young <dyoung@redhat.com>
Link: https://lore.kernel.org/r/20200804044933.1973-2-lijiang@redhat.com
2020-08-07 01:32:00 +02:00
Julia Lawall
1429b568ad x86/crash: Use resource_size()
Use resource_size() rather than a verbose computation on
the end and start fields.

The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)

<smpl>
@@ struct resource ptr; @@
- (ptr.end - ptr.start + 1)
+ resource_size(&ptr)
</smpl>

Signed-off-by: Julia Lawall <Julia.Lawall@inria.fr>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/1577900990-8588-10-git-send-email-Julia.Lawall@inria.fr
2020-01-09 14:40:03 +01:00
Borislav Petkov
9eff303725 x86/crash: Align function arguments on opening braces
... or let function calls stick out and thus remain on a single line,
even if the 80 cols rule is violated by a couple of chars, for better
readability.

No functional changes.

Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: x86@kernel.org
Link: https://lkml.kernel.org/r/20191114172200.19563-1-bp@alien8.de
2019-11-14 18:24:55 +01:00
Lianbo Jiang
7c321eb2b8 x86/kdump: Remove the backup region handling
When the crashkernel kernel command line option is specified, the low
1M memory will always be reserved now. Therefore, it's not necessary to
create a backup region anymore and also no need to copy the contents of
the first 640k to it.

Remove all the code related to handling that backup region.

 [ bp: Massage commit message. ]

Signed-off-by: Lianbo Jiang <lijiang@redhat.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: bhe@redhat.com
Cc: Dave Young <dyoung@redhat.com>
Cc: d.hatayama@fujitsu.com
Cc: dhowells@redhat.com
Cc: ebiederm@xmission.com
Cc: horms@verge.net.au
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jürgen Gross <jgross@suse.com>
Cc: kexec@lists.infradead.org
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: vgoyal@redhat.com
Cc: x86-ml <x86@kernel.org>
Link: https://lkml.kernel.org/r/20191108090027.11082-3-lijiang@redhat.com
2019-11-14 18:24:43 +01:00
Lianbo Jiang
6f599d8423 x86/kdump: Always reserve the low 1M when the crashkernel option is specified
On x86, purgatory() copies the first 640K of memory to a backup region
because the kernel needs those first 640K for the real mode trampoline
during boot, among others.

However, when SME is enabled, the kernel cannot properly copy the old
memory to the backup area but reads only its encrypted contents. The
result is that the crash tool gets invalid pointers when parsing vmcore:

  crash> kmem -s|grep -i invalid
  kmem: dma-kmalloc-512: slab:ffffd77680001c00 invalid freepointer:a6086ac099f0c5a4
  kmem: dma-kmalloc-512: slab:ffffd77680001c00 invalid freepointer:a6086ac099f0c5a4
  crash>

So reserve the remaining low 1M memory when the crashkernel option is
specified (after reserving real mode memory) so that allocated memory
does not fall into the low 1M area and thus the copying of the contents
of the first 640k to a backup region in purgatory() can be avoided
altogether.

This way, it does not need to be included in crash dumps or used for
anything except the trampolines that must live in the low 1M.

 [ bp: Heavily rewrite commit message, flip check logic in
   crash_reserve_low_1M().]

Signed-off-by: Lianbo Jiang <lijiang@redhat.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: bhe@redhat.com
Cc: Dave Young <dyoung@redhat.com>
Cc: d.hatayama@fujitsu.com
Cc: dhowells@redhat.com
Cc: ebiederm@xmission.com
Cc: horms@verge.net.au
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jürgen Gross <jgross@suse.com>
Cc: kexec@lists.infradead.org
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: vgoyal@redhat.com
Cc: x86-ml <x86@kernel.org>
Link: https://lkml.kernel.org/r/20191108090027.11082-2-lijiang@redhat.com
Link: https://bugzilla.kernel.org/show_bug.cgi?id=204793
2019-11-14 13:54:33 +01:00
Nikolas Nyby
4599c6671b x86/crash: Remove unnecessary comparison
The ret comparison and return are unnecessary as of commit f296f26349
("x86/kexec: Remove walk_iomem_res() call with GART type")

elf_header_exclude_ranges() returns ret in any case, with or without this
comparison.

[ tglx: Use a proper commit reference instead of full SHA ]

Signed-off-by: Nikolas Nyby <nikolas@gnu.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20190724041337.8346-1-nikolas@gnu.org
2019-07-24 16:50:15 +02:00
Linus Torvalds
565eb5f8c5 Merge branch 'x86-kdump-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x865 kdump updates from Thomas Gleixner:
 "Yet more kexec/kdump updates:

   - Properly support kexec when AMD's memory encryption (SME) is
     enabled

   - Pass reserved e820 ranges to the kexec kernel so both PCI and SME
     can work"

* 'x86-kdump-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  fs/proc/vmcore: Enable dumping of encrypted memory when SEV was active
  x86/kexec: Set the C-bit in the identity map page table when SEV is active
  x86/kexec: Do not map kexec area as decrypted when SEV is active
  x86/crash: Add e820 reserved ranges to kdump kernel's e820 table
  x86/mm: Rework ioremap resource mapping determination
  x86/e820, ioport: Add a new I/O resource descriptor IORES_DESC_RESERVED
  x86/mm: Create a workarea in the kernel for SME early encryption
  x86/mm: Identify the end of the kernel area to be reserved
2019-07-09 11:52:34 -07:00
Linus Torvalds
5b7a209523 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 small cleanups: removal of superfluous code and coding style
  cleanups mostly"

* 'x86-cleanups-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/kexec: Make variable static and config dependent
  x86/defconfigs: Remove useless UEVENT_HELPER_PATH
  x86/amd_nb: Make hygon_nb_misc_ids static
  x86/tsc: Move inline keyword to the beginning of function declarations
  x86/io_delay: Define IO_DELAY macros in C instead of Kconfig
  x86/io_delay: Break instead of fallthrough in switch statement
2019-07-08 17:27:24 -07:00
Tiezhu Yang
53b7607382 x86/kexec: Make variable static and config dependent
The following sparse warning is emitted:

  arch/x86/kernel/crash.c:59:15:
  warning: symbol 'crash_zero_bytes' was not declared. Should it be static?

The variable is only used in this compilation unit, but it is also only
used when CONFIG_KEXEC_FILE is enabled. Just making it static would result
in a 'defined but not used' warning for CONFIG_KEXEC_FILE=n.

Make it static and move it into the existing CONFIG_KEXEC_FILE section.

[ tglx: Massaged changelog and moved it into the existing ifdef ]

Fixes: dd5f726076 ("kexec: support for kexec on panic using new system call")
Signed-off-by: Tiezhu Yang <kernelpatch@126.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Dave Young <dyoung@redhat.com>
Cc: bp@alien8.de
Cc: hpa@zytor.com
Cc: kexec@lists.infradead.org
Cc: vgoyal@redhat.com
Cc: Vivek Goyal <vgoyal@redhat.com>
Link: https://lkml.kernel.org/r/117ef0c6.3d30.16b87c9cfbf.Coremail.kernelpatch@126.com
2019-06-26 16:02:45 +02:00
Peter Zijlstra
3c88c692c2 x86/stackframe/32: Provide consistent pt_regs
Currently pt_regs on x86_32 has an oddity in that kernel regs
(!user_mode(regs)) are short two entries (esp/ss). This means that any
code trying to use them (typically: regs->sp) needs to jump through
some unfortunate hoops.

Change the entry code to fix this up and create a full pt_regs frame.

This then simplifies various trampolines in ftrace and kprobes, the
stack unwinder, ptrace, kdump and kgdb.

Much thanks to Josh for help with the cleanups!

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-06-25 10:23:47 +02:00
Lianbo Jiang
980621daf3 x86/crash: Add e820 reserved ranges to kdump kernel's e820 table
At present, when using the kexec_file_load() syscall to load the kernel
image and initramfs, for example:

  kexec -s -p xxx

the kernel does not pass the e820 reserved ranges to the second kernel,
which might cause two problems:

 1. MMCONFIG: A device in PCI segment 1 cannot be discovered by the
kernel PCI probing without all the e820 I/O reservations being present
in the e820 table. Which is the case currently, because the kdump kernel
does not have those reservations because the kexec command does not pass
the I/O reservation via the "memmap=xxx" command line option.

Further details courtesy of Bjorn Helgaas¹: I think you should regard
correct MCFG/ECAM usage in the kdump kernel as a requirement. MMCONFIG
(aka ECAM) space is described in the ACPI MCFG table. If you don't have
ECAM:

  (a) PCI devices won't work at all on non-x86 systems that use only
   ECAM for config access,

  (b) you won't be able to access devices on non-0 segments (granted,
  there aren't very many of these yet, but there will be more in the
  future), and

  (c) you won't be able to access extended config space (addresses
  0x100-0xfff), which means none of the Extended Capabilities will be
  available (AER, ACS, ATS, etc).

 2. The second issue is that the SME kdump kernel doesn't work without
the e820 reserved ranges. When SME is active in the kdump kernel, those
reserved regions are still decrypted, but because those reserved ranges
are not present at all in kdump kernel's e820 table, they are accessed
as encrypted. Which is obviously wrong.

 [1]: https://lkml.kernel.org/r/CABhMZUUscS3jUZUSM5Y6EYJK6weo7Mjj5-EAKGvbw0qEe%2B38zw@mail.gmail.com

 [ bp: Heavily massage commit message. ]

Suggested-by: Dave Young <dyoung@redhat.com>
Signed-off-by: Lianbo Jiang <lijiang@redhat.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Baoquan He <bhe@redhat.com>
Cc: Bjorn Helgaas <bjorn.helgaas@gmail.com>
Cc: dave.hansen@linux.intel.com
Cc: Dave Young <dyoung@redhat.com>
Cc: "Gustavo A. R. Silva" <gustavo@embeddedor.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: kexec@lists.infradead.org
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: x86-ml <x86@kernel.org>
Cc: Yi Wang <wang.yi59@zte.com.cn>
Link: https://lkml.kernel.org/r/20190423013007.17838-4-lijiang@redhat.com
2019-06-20 10:05:06 +02:00
Thomas Gleixner
457c899653 treewide: Add SPDX license identifier for missed files
Add SPDX license identifiers to all files which:

 - Have no license information of any form

 - Have EXPORT_.*_SYMBOL_GPL inside which was used in the
   initial scan/conversion to ignore the file

These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:

  GPL-2.0-only

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-21 10:50:45 +02:00
Gustavo A. R. Silva
4df4309587 x86/kexec/crash: Use struct_size() in vzalloc()
One of the more common cases of allocation size calculations is finding the
size of a structure that has a zero-sized array at the end, along with
memory for some number of elements for that array. For example:

struct foo {
    int stuff;
    struct boo entry[];
};

instance = vzalloc(sizeof(struct foo) + count * sizeof(struct boo));

Instead of leaving these open-coded and prone to type mistakes, use the new
struct_size() helper:

   instance = vzalloc(struct_size(instance, entry, count));

This code was detected with the help of Coccinelle.

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Link: https://lkml.kernel.org/r/20190403184230.GA5295@embeddedor
2019-04-05 13:18:38 +02:00
Dave Young
993a110319 x86/kexec: Fix a kexec_file_load() failure
Commit

  b6664ba42f ("s390, kexec_file: drop arch_kexec_mem_walk()")

changed the behavior of kexec_locate_mem_hole(): it will try to allocate
free memory only when kbuf.mem is initialized to zero.

However, x86's kexec_file_load() implementation reuses a struct
kexec_buf allocated on the stack and its kbuf.mem member gets set by
each kexec_add_buffer() invocation.

The second kexec_add_buffer() will reuse the same kbuf but not
reinitialize kbuf.mem.

Therefore, explictily reset kbuf.mem each time in order for
kexec_locate_mem_hole() to locate a free memory region each time.

 [ bp: massage commit message. ]

Fixes: b6664ba42f ("s390, kexec_file: drop arch_kexec_mem_walk()")
Signed-off-by: Dave Young <dyoung@redhat.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Baoquan He <bhe@redhat.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: AKASHI Takahiro <takahiro.akashi@linaro.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Philipp Rudo <prudo@linux.vnet.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Yannik Sembritzki <yannik@sembritzki.me>
Cc: Yi Wang <wang.yi59@zte.com.cn>
Cc: kexec@lists.infradead.org
Cc: x86-ml <x86@kernel.org>
Link: https://lkml.kernel.org/r/20181228011247.GA9999@dhcp-128-65.nay.redhat.com
2019-01-15 12:12:50 +01:00
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
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
eb7dae947e x86: kexec_file: clean up prepare_elf64_headers()
Removing bufp variable in prepare_elf64_headers() makes the code simpler
and more understandable.

Link: http://lkml.kernel.org/r/20180306102303.9063-7-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
8d5f894a31 x86: kexec_file: lift CRASH_MAX_RANGES limit on crash_mem buffer
While CRASH_MAX_RANGES (== 16) seems to be good enough, fixed-number
array is not a good idea in general.

In this patch, size of crash_mem buffer is calculated as before and the
buffer is now dynamically allocated.  This change also allows removing
crash_elf_data structure.

Link: http://lkml.kernel.org/r/20180306102303.9063-6-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
c72c7e6709 x86: kexec_file: remove X86_64 dependency from prepare_elf64_headers()
The code guarded by CONFIG_X86_64 is necessary on some architectures
which have a dedicated kernel mapping outside of linear memory mapping.
(arm64 is among those.)

In this patch, an additional argument, kernel_map, is added to enable/
disable the code removing #ifdef.

Link: http://lkml.kernel.org/r/20180306102303.9063-5-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
cbe6601617 x86: kexec_file: purge system-ram walking from prepare_elf64_headers()
While prepare_elf64_headers() in x86 looks pretty generic for other
architectures' use, it contains some code which tries to list crash
memory regions by walking through system resources, which is not always
architecture agnostic.  To make this function more generic, the related
code should be purged.

In this patch, prepare_elf64_headers() simply scans crash_mem buffer
passed and add all the listed regions to elf header as a PT_LOAD
segment.  So walk_system_ram_res(prepare_elf64_headers_callback) have
been moved forward before prepare_elf64_headers() where the callback,
prepare_elf64_headers_callback(), is now responsible for filling up
crash_mem buffer.

Meanwhile exclude_elf_header_ranges() used to be called every time in
this callback it is rather redundant and now called only once in
prepare_elf_headers() as well.

Link: http://lkml.kernel.org/r/20180306102303.9063-4-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
Baoquan He
339b2ae0cd x86/apic: Fix restoring boot IRQ mode in reboot and kexec/kdump
This is a regression fix.

Before, to fix erratum AVR31, the following commit:

  522e664644 ("x86/apic: Disable I/O APIC before shutdown of the local APIC")

... moved the lapic_shutdown() call to after disable_IO_APIC() in the reboot
and kexec/kdump code paths.

This introduced the following regression: disable_IO_APIC() not only clears
the IO-APIC, but it also restores boot IRQ mode by setting the
LAPIC/APIC/IMCR, calling lapic_shutdown() after disable_IO_APIC() will
disable LAPIC and ruin the possible virtual wire mode setting which
the code has been trying to do all along.

The consequence is that a KVM guest kernel always prints the warning below
during kexec/kdump as the kernel boots up:

  [    0.001000] WARNING: CPU: 0 PID: 0 at arch/x86/kernel/apic/apic.c:1467 setup_local_APIC+0x228/0x330
  [    ........]
  [    0.001000] Call Trace:
  [    0.001000]  apic_bsp_setup+0x56/0x74
  [    0.001000]  x86_late_time_init+0x11/0x16
  [    0.001000]  start_kernel+0x3c9/0x486
  [    0.001000]  secondary_startup_64+0xa5/0xb0
  [    ........]
  [    0.001000] masked ExtINT on CPU#0

To fix this, just call clear_IO_APIC() to stop the IO-APIC where
disable_IO_APIC() was called, and call restore_boot_irq_mode() to
restore boot IRQ mode before a reboot or a kexec/kdump jump.

Signed-off-by: Baoquan He <bhe@redhat.com>
Reviewed-by: Eric W. Biederman <ebiederm@xmission.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: douly.fnst@cn.fujitsu.com
Cc: joro@8bytes.org
Cc: prarit@redhat.com
Cc: stable@vger.kernel.org
Cc: uobergfe@redhat.com
Fixes: commit 522e664644 ("x86/apic: Disable I/O APIC before shutdown of the local APIC")
Link: http://lkml.kernel.org/r/20180214054656.3780-4-bhe@redhat.com
[ Rewrote the changelog. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-02-17 11:47:45 +01:00
kbuild test robot
9275b933d4 resource: Fix resource_size.cocci warnings
arch/x86/kernel/crash.c:627:34-37: ERROR: Missing resource_size with res
arch/x86/kernel/crash.c:528:16-19: ERROR: Missing resource_size with res

 Use resource_size function on resource object
 instead of explicit computation.

Generated by: scripts/coccinelle/api/resource_size.cocci

Fixes: 1d2e733b13 ("resource: Provide resource struct in resource walk callback")
Signed-off-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Juergen Gross <jgross@suse.com>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Brijesh Singh <brijesh.singh@amd.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: kbuild-all@01.org
Cc: tipbuild@zytor.com
Cc: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20171107191801.GA91887@lkp-snb01
2017-11-07 20:44:56 +01:00
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
Xunlei Pang
203e9e4121 kexec: move vmcoreinfo out of the kernel's .bss section
As Eric said,
 "what we need to do is move the variable vmcoreinfo_note out of the
  kernel's .bss section. And modify the code to regenerate and keep this
  information in something like the control page.

  Definitely something like this needs a page all to itself, and ideally
  far away from any other kernel data structures. I clearly was not
  watching closely the data someone decided to keep this silly thing in
  the kernel's .bss section."

This patch allocates extra pages for these vmcoreinfo_XXX variables, one
advantage is that it enhances some safety of vmcoreinfo, because
vmcoreinfo now is kept far away from other kernel data structures.

Link: http://lkml.kernel.org/r/1493281021-20737-1-git-send-email-xlpang@redhat.com
Signed-off-by: Xunlei Pang <xlpang@redhat.com>
Tested-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Suggested-by: Eric Biederman <ebiederm@xmission.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Dave Young <dyoung@redhat.com>
Cc: Hari Bathini <hbathini@linux.vnet.ibm.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 16:25:59 -07:00
Ingo Molnar
08b46d5dd8 x86/boot/e820: Clean up the E820 table size define names
We've got a number of defines related to the E820 table and its size:

	E820MAP
	E820NR
	E820_X_MAX
	E820MAX

The first two denote byte offsets into the zeropage (struct boot_params),
and can are not used in the kernel and can be removed.

The E820_*_MAX values have an inconsistent structure and it's unclear in any
case what they mean. 'X' presuably goes for extended - but it's not very
expressive altogether.

Change these over to:

	E820_MAX_ENTRIES_ZEROPAGE
	E820_MAX_ENTRIES

... which are self-explanatory names.

No change in functionality.

Cc: Alex Thorlton <athorlton@sgi.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Huang, Ying <ying.huang@intel.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul Jackson <pj@sgi.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Tejun Heo <tj@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Wei Yang <richard.weiyang@gmail.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-01-28 22:55:23 +01:00
Ingo Molnar
09821ff1d5 x86/boot/e820: Prefix the E820_* type names with "E820_TYPE_"
So there's a number of constants that start with "E820" but which
are not types - these create a confusing mixture when seen together
with 'enum e820_type' values:

	E820MAP
	E820NR
	E820_X_MAX
	E820MAX

To better differentiate the 'enum e820_type' values prefix them
with E820_TYPE_.

No change in functionality.

Cc: Alex Thorlton <athorlton@sgi.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Huang, Ying <ying.huang@intel.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul Jackson <pj@sgi.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Tejun Heo <tj@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Wei Yang <richard.weiyang@gmail.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-01-28 22:55:22 +01:00
Ingo Molnar
61a5010163 x86/boot/e820: Rename everything to e820_table
No change in functionality.

Cc: Alex Thorlton <athorlton@sgi.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Huang, Ying <ying.huang@intel.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul Jackson <pj@sgi.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Tejun Heo <tj@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Wei Yang <richard.weiyang@gmail.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-01-28 09:33:16 +01:00
Ingo Molnar
acd4c04872 x86/boot/e820: Rename 'e820_map' variables to 'e820_array'
In line with the rename to 'struct e820_array', harmonize the naming of common e820
table variable names as well:

 e820          =>  e820_array
 e820_saved    =>  e820_array_saved
 e820_map      =>  e820_array
 initial_e820  =>  e820_array_init

This makes the variable names more consistent  and easier to grep for.

No change in functionality.

Cc: Alex Thorlton <athorlton@sgi.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Huang, Ying <ying.huang@intel.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul Jackson <pj@sgi.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Tejun Heo <tj@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Wei Yang <richard.weiyang@gmail.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-01-28 09:33:15 +01:00
Ingo Molnar
8ec67d97bf x86/boot/e820: Rename the basic e820 data types to 'struct e820_entry' and 'struct e820_array'
The 'e820entry' and 'e820map' names have various annoyances:

 - the missing underscore departs from the usual kernel style
   and makes the code look weird,

 - in the past I kept confusing the 'map' with the 'entry', because
   a 'map' is ambiguous in that regard,

 - it's not really clear from the 'e820map' that this is a regular
   C array.

Rename them to 'struct e820_entry' and 'struct e820_array' accordingly.

( Leave the legacy UAPI header alone but do the rename in the bootparam.h
  and e820/types.h file - outside tools relying on these defines should
  either adjust their code, or should use the legacy header, or should
  create their private copies for the definitions. )

No change in functionality.

Cc: Alex Thorlton <athorlton@sgi.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Huang, Ying <ying.huang@intel.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul Jackson <pj@sgi.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Tejun Heo <tj@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Wei Yang <richard.weiyang@gmail.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-01-28 09:33:14 +01:00
Ingo Molnar
5520b7e7d2 x86/boot/e820: Remove spurious asm/e820/api.h inclusions
A commonly used lowlevel x86 header, asm/pgtable.h, includes asm/e820/api.h
spuriously, without making direct use of it.

Removing it is not simple: over the years various .c code learned to rely
on this indirect inclusion.

Remove the unnecessary include - this should speed up the kernel build a bit,
as a large header is not included anymore in totally unrelated code.

Cc: Alex Thorlton <athorlton@sgi.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Huang, Ying <ying.huang@intel.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul Jackson <pj@sgi.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Tejun Heo <tj@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Wei Yang <richard.weiyang@gmail.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-01-28 09:31:14 +01:00
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
Hidehiro Kawai
0ee59413c9 x86/panic: replace smp_send_stop() with kdump friendly version in panic path
Daniel Walker reported problems which happens when
crash_kexec_post_notifiers kernel option is enabled
(https://lkml.org/lkml/2015/6/24/44).

In that case, smp_send_stop() is called before entering kdump routines
which assume other CPUs are still online.  As the result, for x86, kdump
routines fail to save other CPUs' registers and disable virtualization
extensions.

To fix this problem, call a new kdump friendly function,
crash_smp_send_stop(), instead of the smp_send_stop() when
crash_kexec_post_notifiers is enabled.  crash_smp_send_stop() is a weak
function, and it just call smp_send_stop().  Architecture codes should
override it so that kdump can work appropriately.  This patch only
provides x86-specific version.

For Xen's PV kernel, just keep the current behavior.

NOTES:

- Right solution would be to place crash_smp_send_stop() before
  __crash_kexec() invocation in all cases and remove smp_send_stop(), but
  we can't do that until all architectures implement own
  crash_smp_send_stop()

- crash_smp_send_stop()-like work is still needed by
  machine_crash_shutdown() because crash_kexec() can be called without
  entering panic()

Fixes: f06e5153f4 (kernel/panic.c: add "crash_kexec_post_notifiers" option)
Link: http://lkml.kernel.org/r/20160810080948.11028.15344.stgit@sysi4-13.yrl.intra.hitachi.co.jp
Signed-off-by: Hidehiro Kawai <hidehiro.kawai.ez@hitachi.com>
Reported-by: Daniel Walker <dwalker@fifo99.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Daniel Walker <dwalker@fifo99.com>
Cc: Xunlei Pang <xpang@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: David Vrabel <david.vrabel@citrix.com>
Cc: Toshi Kani <toshi.kani@hpe.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: David Daney <david.daney@cavium.com>
Cc: Aaro Koskinen <aaro.koskinen@iki.fi>
Cc: "Steven J. Hill" <steven.hill@cavium.com>
Cc: Corey Minyard <cminyard@mvista.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-10-11 15:06:32 -07:00
Paul Gortmaker
186f43608a x86/kernel: Audit and remove any unnecessary uses of module.h
Historically a lot of these existed because we did not have
a distinction between what was modular code and what was providing
support to modules via EXPORT_SYMBOL and friends.  That changed
when we forked out support for the latter into the export.h file.

This means we should be able to reduce the usage of module.h
in code that is obj-y Makefile or bool Kconfig.  The advantage
in doing so is that module.h itself sources about 15 other headers;
adding significantly to what we feed cpp, and it can obscure what
headers we are effectively using.

Since module.h was the source for init.h (for __init) and for
export.h (for EXPORT_SYMBOL) we consider each obj-y/bool instance
for the presence of either and replace as needed.  Build testing
revealed some implicit header usage that was fixed up accordingly.

Note that some bool/obj-y instances remain since module.h is
the header for some exception table entry stuff, and for things
like __init_or_module (code that is tossed when MODULES=n).

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20160714001901.31603-4-paul.gortmaker@windriver.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-07-14 15:06:41 +02:00
Toshi Kani
f296f26349 x86/kexec: Remove walk_iomem_res() call with GART type
There is no longer any driver inserting a "GART" region in the
kernel since

  707d4eefbd ("Revert "[PATCH] Insert GART region into resource map"").

Remove the call to walk_iomem_res() with "GART" type, its
callback function, and GART-specific variables set by the
callback.

Signed-off-by: Toshi Kani <toshi.kani@hpe.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Dave Young <dyoung@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Chun-Yi <joeyli.kernel@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Lee, Chun-Yi <joeyli.kernel@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Luis R. Rodriguez <mcgrof@suse.com>
Cc: Minfei Huang <mnfhuang@gmail.com>
Cc: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Takao Indoh <indou.takao@jp.fujitsu.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Toshi Kani <toshi.kani@hp.com>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Cc: kexec@lists.infradead.org
Cc: linux-arch@vger.kernel.org
Cc: linux-mm <linux-mm@kvack.org>
Link: http://lkml.kernel.org/r/1453841853-11383-16-git-send-email-bp@alien8.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-01-30 09:49:59 +01:00
Toshi Kani
f0f4711aa1 x86, kexec, nvdimm: Use walk_iomem_res_desc() for iomem search
Change the callers of walk_iomem_res() scanning for the
following resources by name to use walk_iomem_res_desc()
instead.

 "ACPI Tables"
 "ACPI Non-volatile Storage"
 "Persistent Memory (legacy)"
 "Crash kernel"

Note, the caller of walk_iomem_res() with "GART" will be removed
in a later patch.

Signed-off-by: Toshi Kani <toshi.kani@hpe.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Dave Young <dyoung@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Chun-Yi <joeyli.kernel@gmail.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Lee, Chun-Yi <joeyli.kernel@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Luis R. Rodriguez <mcgrof@suse.com>
Cc: Minfei Huang <mnfhuang@gmail.com>
Cc: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Takao Indoh <indou.takao@jp.fujitsu.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Toshi Kani <toshi.kani@hp.com>
Cc: kexec@lists.infradead.org
Cc: linux-arch@vger.kernel.org
Cc: linux-mm <linux-mm@kvack.org>
Cc: linux-nvdimm@lists.01.org
Link: http://lkml.kernel.org/r/1453841853-11383-15-git-send-email-bp@alien8.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-01-30 09:49:59 +01:00
Takao Indoh
da06a43d3f perf, x86: Stop Intel PT before kdump starts
This patch stops Intel PT logging and saves its registers in memory
before kdump is started. This feature is needed to prevent Intel PT from
overwriting its log buffer after panic, and saved registers are needed to
find the last position where Intel PT wrote data.

After the crash dump is captured by kdump, users can retrieve the log buffer
from the vmcore and use it to investigate bad kernel behavior.

Signed-off-by: Takao Indoh <indou.takao@jp.fujitsu.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin<alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: H.Peter Anvin <hpa@zytor.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: Vivek Goyal <vgoyal@redhat.com>
Link: http://lkml.kernel.org/r/1446614553-6072-3-git-send-email-indou.takao@jp.fujitsu.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-11-23 09:58:26 +01:00
Minfei Huang
e9c40d257f x86/kexec: Remove obsolete 'in_crash_kexec' flag
Previously, UV NMI used the 'in_crash_kexec' flag to determine whether
we are in a kdump kernel or not:

  5edd19af18 ("x86, UV: Make kdump avoid stack dumps")

But this flags was removed in the following commit:

  9c48f1c629 ("x86, nmi: Wire up NMI handlers to new routines")

Since it isn't used any more, remove it.

Signed-off-by: Minfei Huang <mnfhuang@gmail.com>
Acked-by: Don Zickus <dzickus@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: cpw@sgi.com
Cc: kexec@lists.infradead.org
Cc: mhuang@redhat.com
Link: http://lkml.kernel.org/r/1444070155-17934-1-git-send-email-mhuang@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-10-12 09:43:11 +02:00
Lee, Chun-Yi
e3c41e37b0 x86/kexec: Fix kexec crash in syscall kexec_file_load()
The original bug is a page fault crash that sometimes happens
on big machines when preparing ELF headers:

    BUG: unable to handle kernel paging request at ffffc90613fc9000
    IP: [<ffffffff8103d645>] prepare_elf64_ram_headers_callback+0x165/0x260

The bug is caused by us under-counting the number of memory ranges
and subsequently not allocating enough ELF header space for them.
The bug is typically masked on smaller systems, because the ELF header
allocation is rounded up to the next page.

This patch modifies the code in fill_up_crash_elf_data() by using
walk_system_ram_res() instead of walk_system_ram_range() to correctly
count the max number of crash memory ranges. That's because the
walk_system_ram_range() filters out small memory regions that
reside in the same page, but walk_system_ram_res() does not.

Here's how I found the bug:

After tracing prepare_elf64_headers() and prepare_elf64_ram_headers_callback(),
the code uses walk_system_ram_res() to fill-in crash memory regions information
to the program header, so it counts those small memory regions that
reside in a page area.

But, when the kernel was using walk_system_ram_range() in
fill_up_crash_elf_data() to count the number of crash memory regions,
it filters out small regions.

I printed those small memory regions, for example:

  kexec: Get nr_ram ranges. vaddr=0xffff880077592258 paddr=0x77592258, sz=0xdc0

Based on the code in walk_system_ram_range(), this memory region
will be filtered out:

  pfn = (0x77592258 + 0x1000 - 1) >> 12 = 0x77593
  end_pfn = (0x77592258 + 0xfc0 -1 + 1) >> 12 = 0x77593
  end_pfn - pfn = 0x77593 - 0x77593 = 0  <=== if (end_pfn > pfn) is FALSE

So, the max_nr_ranges that's counted by the kernel doesn't include
small memory regions - causing us to under-allocate the required space.
That causes the page fault crash that happens in a later code path
when preparing ELF headers.

This bug is not easy to reproduce on small machines that have few
CPUs, because the allocated page aligned ELF buffer has more free
space to cover those small memory regions' PT_LOAD headers.

Signed-off-by: Lee, Chun-Yi <jlee@suse.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Baoquan He <bhe@redhat.com>
Cc: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Takashi Iwai <tiwai@suse.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: kexec@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Cc: <stable@vger.kernel.org>
Link: http://lkml.kernel.org/r/1443531537-29436-1-git-send-email-jlee@suse.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-10-02 09:13:06 +02:00
Stephen Rothwell
d6472302f2 x86/mm: Decouple <linux/vmalloc.h> from <asm/io.h>
Nothing in <asm/io.h> uses anything from <linux/vmalloc.h>, so
remove it from there and fix up the resulting build problems
triggered on x86 {64|32}-bit {def|allmod|allno}configs.

The breakages were triggering in places where x86 builds relied
on vmalloc() facilities but did not include <linux/vmalloc.h>
explicitly and relied on the implicit inclusion via <asm/io.h>.

Also add:

  - <linux/init.h> to <linux/io.h>
  - <asm/pgtable_types> to <asm/io.h>

... which were two other implicit header file dependencies.

Suggested-by: David Miller <davem@davemloft.net>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
[ Tidied up the changelog. ]
Acked-by: David Miller <davem@davemloft.net>
Acked-by: Takashi Iwai <tiwai@suse.de>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Vinod Koul <vinod.koul@intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Anton Vorontsov <anton@enomsg.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Colin Cross <ccross@android.com>
Cc: David Vrabel <david.vrabel@citrix.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: James E.J. Bottomley <JBottomley@odin.com>
Cc: Jaroslav Kysela <perex@perex.cz>
Cc: K. Y. Srinivasan <kys@microsoft.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Kristen Carlson Accardi <kristen@linux.intel.com>
Cc: Len Brown <lenb@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rafael J. Wysocki <rjw@rjwysocki.net>
Cc: Suma Ramars <sramars@cisco.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-06-03 12:02:00 +02:00
Andy Lutomirski
f39b6f0ef8 x86/asm/entry: Change all 'user_mode_vm()' calls to 'user_mode()'
user_mode_vm() and user_mode() are now the same.  Change all callers
of user_mode_vm() to user_mode().

The next patch will remove the definition of user_mode_vm.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brad Spengler <spender@grsecurity.net>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/43b1f57f3df70df5a08b0925897c660725015554.1426728647.git.luto@kernel.org
[ Merged to a more recent kernel. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-03-23 11:14:17 +01:00
Jiang Liu
8643e28da2 x86, irq: Move IOAPIC related declarations from hw_irq.h into io_apic.h
Clean up code by moving IOAPIC related declarations from hw_irq.h into
io_apic.h.

Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: H. Peter Anvin <hpa@linux.intel.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Rafael J. Wysocki <rjw@rjwysocki.net>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Prarit Bhargava <prarit@redhat.com>
Cc: Grant Likely <grant.likely@linaro.org>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Matt Fleming <matt.fleming@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Christian Gmeiner <christian.gmeiner@gmail.com>
Cc: Aubrey <aubrey.li@linux.intel.com>
Cc: Ryan Desfosses <ryan@desfo.org>
Cc: Quentin Lambert <lambert.quentin@gmail.com>
Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: http://lkml.kernel.org/r/1414397531-28254-14-git-send-email-jiang.liu@linux.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-12-16 14:08:17 +01:00
Baoquan He
a2d6aa8fa0 kexec: check if crashk_res_low exists when exclude it from crash mem ranges
Add a check if crashk_res_low exists just like GART region does.  If
crashk_res_low doesn't exist, calling exclude_mem_range is unnecessary.

Meanwhile, since crashk_res_low has been initialized at definition, it's
safe just use "if (crashk_low_res.end)" to check if it's exist.  And this
can make it consistent with other places of check.

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
Vivek Goyal
74ca317c26 kexec: create a new config option CONFIG_KEXEC_FILE for new syscall
Currently new system call kexec_file_load() and all the associated code
compiles if CONFIG_KEXEC=y.  But new syscall also compiles purgatory
code which currently uses gcc option -mcmodel=large.  This option seems
to be available only gcc 4.4 onwards.

Hiding new functionality behind a new config option will not break
existing users of old gcc.  Those who wish to enable new functionality
will require new gcc.  Having said that, I am trying to figure out how
can I move away from using -mcmodel=large but that can take a while.

I think there are other advantages of introducing this new config
option.  As this option will be enabled only on x86_64, other arches
don't have to compile generic kexec code which will never be used.  This
new code selects CRYPTO=y and CRYPTO_SHA256=y.  And all other arches had
to do this for CONFIG_KEXEC.  Now with introduction of new config
option, we can remove crypto dependency from other arches.

Now CONFIG_KEXEC_FILE is available only on x86_64.  So whereever I had
CONFIG_X86_64 defined, I got rid of that.

For CONFIG_KEXEC_FILE, instead of doing select CRYPTO=y, I changed it to
"depends on CRYPTO=y".  This should be safer as "select" is not
recursive.

Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Tested-by: Shaun Ruffell <sruffell@digium.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-08-29 16:28:16 -07:00
Vivek Goyal
dd5f726076 kexec: support for kexec on panic using new system call
This patch adds support for loading a kexec on panic (kdump) kernel usning
new system call.

It prepares ELF headers for memory areas to be dumped and for saved cpu
registers.  Also prepares the memory map for second kernel and limits its
boot to reserved areas only.

Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Matthew Garrett <mjg59@srcf.ucam.org>
Cc: Greg Kroah-Hartman <greg@kroah.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: WANG Chao <chaowang@redhat.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-08-08 15:57:33 -07:00
Borislav Petkov
5314feebab x86, crash: Unify ifdef
Merge two back-to-back CONFIG_X86_32 ifdefs into one.

Signed-off-by: Borislav Petkov <bp@suse.de>
Link: http://lkml.kernel.org/r/1394633584-5509-3-git-send-email-bp@alien8.de
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-03-13 15:32:44 -07:00
Paul Gortmaker
663b55b9b3 x86: Delete non-required instances of include <linux/init.h>
None of these files are actually using any __init type directives
and hence don't need to include <linux/init.h>.  Most are just a
left over from __devinit and __cpuinit removal, or simply due to
code getting copied from one driver to the next.

[ hpa: undid incorrect removal from arch/x86/kernel/head_32.S ]

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Link: http://lkml.kernel.org/r/1389054026-12947-1-git-send-email-paul.gortmaker@windriver.com
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2014-01-06 21:25:18 -08:00
Fenghua Yu
522e664644 x86/apic: Disable I/O APIC before shutdown of the local APIC
In reboot and crash path, when we shut down the local APIC, the I/O APIC is
still active. This may cause issues because external interrupts
can still come in and disturb the local APIC during shutdown process.

To quiet external interrupts, disable I/O APIC before shutdown local APIC.

Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Link: http://lkml.kernel.org/r/1382578212-4677-1-git-send-email-fenghua.yu@intel.com
Cc: <stable@kernel.org>
[ I suppose the 'issue' is a hang during shutdown. It's a fine change nevertheless. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-11-07 10:12:37 +01:00
Yoshihiro YUNOMAE
17405453f4 x86/ioapic/kcrash: Prevent crash_kexec() from deadlocking on ioapic_lock
Prevent crash_kexec() from deadlocking on ioapic_lock. When
crash_kexec() is executed on a CPU, the CPU will take ioapic_lock
in disable_IO_APIC(). So if the cpu gets an NMI while locking
ioapic_lock, a deadlock will happen.

In this patch, ioapic_lock is zapped/initialized before disable_IO_APIC().

You can reproduce this deadlock the following way:

1. Add mdelay(1000) after raw_spin_lock_irqsave() in
   native_ioapic_set_affinity()@arch/x86/kernel/apic/io_apic.c

   Although the deadlock can occur without this modification, it will increase
   the potential of the deadlock problem.

2. Build and install the kernel

3. Set up the OS which will run panic() and kexec when NMI is injected
    # echo "kernel.unknown_nmi_panic=1" >> /etc/sysctl.conf
    # vim /etc/default/grub
      add "nmi_watchdog=0 crashkernel=256M" in GRUB_CMDLINE_LINUX line
    # grub2-mkconfig

4. Reboot the OS

5. Run following command for each vcpu on the guest
    # while true; do echo <CPU num> > /proc/irq/<IO-APIC-edge or IO-APIC-fasteoi>/smp_affinitity; done;
   By running this command, cpus will get ioapic_lock for setting affinity.

6. Inject NMI (push a dump button or execute 'virsh inject-nmi <domain>' if you
   use VM). After injecting NMI, panic() is called in an nmi-handler context.
   Then, kexec will normally run in panic(), but the operation will be stopped
   by deadlock on ioapic_lock in crash_kexec()->machine_crash_shutdown()->
   native_machine_crash_shutdown()->disable_IO_APIC()->clear_IO_APIC()->
   clear_IO_APIC_pin()->ioapic_read_entry().

Signed-off-by: Yoshihiro YUNOMAE <yoshihiro.yunomae.ez@hitachi.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Gleb Natapov <gleb@redhat.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Hidehiro Kawai <hidehiro.kawai.ez@hitachi.com>
Cc: Sebastian Andrzej Siewior <sebastian@breakpoint.cc>
Cc: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: yrl.pp-manager.tt@hitachi.com
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Seiji Aguchi <seiji.aguchi@hds.com>
Link: http://lkml.kernel.org/r/20130820070107.28245.83806.stgit@yunodevel
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-08-20 09:26:33 +02:00
Zhang Yanfei
0ca0d818cb x86/kexec: crash_vmclear_local_vmcss needs __rcu
This removes the sparse warning:
arch/x86/kernel/crash.c:49:32: sparse: incompatible types in comparison expression (different address spaces)

Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2012-12-11 19:55:23 -02:00
Zhang Yanfei
f23d1f4a11 x86/kexec: VMCLEAR VMCSs loaded on all cpus if necessary
This patch provides a way to VMCLEAR VMCSs related to guests
on all cpus before executing the VMXOFF when doing kdump. This
is used to ensure the VMCSs in the vmcore updated and
non-corrupted.

Signed-off-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Acked-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
2012-12-06 18:25:36 +02:00