Linux kernel source tree
Go to file
Konstantin Khlebnikov 246ff09f89 x86/MCE/AMD: Do not use rdmsr_safe_on_cpu() in smca_configure()
... because interrupts are disabled that early and sending IPIs can
deadlock:

  BUG: sleeping function called from invalid context at kernel/sched/completion.c:99
  in_atomic(): 1, irqs_disabled(): 1, non_block: 0, pid: 0, name: swapper/1
  no locks held by swapper/1/0.
  irq event stamp: 0
  hardirqs last  enabled at (0): [<0000000000000000>] 0x0
  hardirqs last disabled at (0): [<ffffffff8106dda9>] copy_process+0x8b9/0x1ca0
  softirqs last  enabled at (0): [<ffffffff8106dda9>] copy_process+0x8b9/0x1ca0
  softirqs last disabled at (0): [<0000000000000000>] 0x0
  Preemption disabled at:
  [<ffffffff8104703b>] start_secondary+0x3b/0x190
  CPU: 1 PID: 0 Comm: swapper/1 Not tainted 5.5.0-rc2+ #1
  Hardware name: GIGABYTE MZ01-CE1-00/MZ01-CE1-00, BIOS F02 08/29/2018
  Call Trace:
   dump_stack
   ___might_sleep.cold.92
   wait_for_completion
   ? generic_exec_single
   rdmsr_safe_on_cpu
   ? wrmsr_on_cpus
   mce_amd_feature_init
   mcheck_cpu_init
   identify_cpu
   identify_secondary_cpu
   smp_store_cpu_info
   start_secondary
   secondary_startup_64

The function smca_configure() is called only on the current CPU anyway,
therefore replace rdmsr_safe_on_cpu() with atomic rdmsr_safe() and avoid
the IPI.

 [ bp: Update commit message. ]

Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Yazen Ghannam <yazen.ghannam@amd.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: linux-edac <linux-edac@vger.kernel.org>
Cc: <stable@vger.kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: x86-ml <x86@kernel.org>
Link: https://lkml.kernel.org/r/157252708836.3876.4604398213417262402.stgit@buzz
2019-12-17 09:39:33 +01:00
arch x86/MCE/AMD: Do not use rdmsr_safe_on_cpu() in smca_configure() 2019-12-17 09:39:33 +01:00
block block: fix memleak of bio integrity data 2019-12-05 11:38:36 -07:00
certs certs: Add wrapper function to check blacklisted binary hash 2019-11-12 12:25:50 +11:00
crypto Merge git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 2019-11-25 19:49:58 -08:00
Documentation powerpc updates for 5.5 #2 2019-12-06 13:36:31 -08:00
drivers Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2019-12-08 13:28:11 -08:00
fs 9 cifs/smb3 fixes: two timestamp fixes, one oops fix (during oplock break) for stable, two fixes found in multichannel testing, two fixes for file create when using modeforsid mount parm 2019-12-08 12:12:18 -08:00
include Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2019-12-08 13:28:11 -08:00
init init/Kconfig: fix indentation 2019-12-04 19:44:13 -08:00
ipc y2038: remove CONFIG_64BIT_TIME 2019-11-15 14:38:27 +01:00
kernel Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2019-12-08 13:28:11 -08:00
lib lib/: fix Kconfig indentation 2019-12-07 11:00:19 -08:00
LICENSES LICENSES: Rename other to deprecated 2019-05-03 06:34:32 -06:00
mm Merge branch 'akpm' (patches from Andrew) 2019-12-05 09:46:26 -08:00
net Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2019-12-08 13:28:11 -08:00
samples samples/bpf: Fix broken xdp_rxq_info due to map order assumptions 2019-12-04 17:54:15 -08:00
scripts Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2019-12-08 13:28:11 -08:00
security + Features 2019-12-03 12:51:35 -08:00
sound sound updates #2 for 5.5-rc1 2019-12-06 13:06:14 -08:00
tools Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2019-12-08 13:28:11 -08:00
usr arch: sembuf.h: make uapi asm/sembuf.h self-contained 2019-12-04 19:44:14 -08:00
virt KVM: Fix jump label out_free_* in kvm_init() 2019-11-23 11:29:17 +01:00
.clang-format clang-format: Update with the latest for_each macro list 2019-08-31 10:00:51 +02:00
.cocciconfig
.get_maintainer.ignore Opt out of scripts/get_maintainer.pl 2019-05-16 10:53:40 -07:00
.gitattributes .gitattributes: use 'dts' diff driver for dts files 2019-12-04 19:44:11 -08:00
.gitignore modpost: dump missing namespaces into a single modules.nsdeps file 2019-11-11 20:10:01 +09:00
.mailmap Merge mainline/master into arm/fixes 2019-12-05 13:18:54 -08:00
COPYING COPYING: use the new text with points to the license files 2018-03-23 12:41:45 -06:00
CREDITS Linux 5.4-rc4 2019-10-29 04:43:29 -06:00
Kbuild kbuild: do not descend to ./Kbuild when cleaning 2019-08-21 21:03:58 +09:00
Kconfig docs: kbuild: convert docs to ReST and rename to *.rst 2019-06-14 14:21:21 -06:00
MAINTAINERS Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2019-12-08 13:28:11 -08:00
Makefile Linux 5.5-rc1 2019-12-08 14:57:55 -08:00
README Drop all 00-INDEX files from Documentation/ 2018-09-09 15:08:58 -06:00

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.