Pull VFS updates from Al Viro,
Misc cleanups all over the place, mainly wrt /proc interfaces (switch
create_proc_entry to proc_create(), get rid of the deprecated
create_proc_read_entry() in favor of using proc_create_data() and
seq_file etc).
7kloc removed.
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (204 commits)
don't bother with deferred freeing of fdtables
proc: Move non-public stuff from linux/proc_fs.h to fs/proc/internal.h
proc: Make the PROC_I() and PDE() macros internal to procfs
proc: Supply a function to remove a proc entry by PDE
take cgroup_open() and cpuset_open() to fs/proc/base.c
ppc: Clean up scanlog
ppc: Clean up rtas_flash driver somewhat
hostap: proc: Use remove_proc_subtree()
drm: proc: Use remove_proc_subtree()
drm: proc: Use minor->index to label things, not PDE->name
drm: Constify drm_proc_list[]
zoran: Don't print proc_dir_entry data in debug
reiserfs: Don't access the proc_dir_entry in r_open(), r_start() r_show()
proc: Supply an accessor for getting the data from a PDE's parent
airo: Use remove_proc_subtree()
rtl8192u: Don't need to save device proc dir PDE
rtl8187se: Use a dir under /proc/net/r8180/
proc: Add proc_mkdir_data()
proc: Move some bits from linux/proc_fs.h to linux/{of.h,signal.h,tty.h}
proc: Move PDE_NET() to fs/proc/proc_net.c
...
Pull x86/efi changes from Peter Anvin:
"The bulk of these changes are cleaning up the efivars handling and
breaking it up into a tree of files. There are a number of fixes as
well.
The entire changeset is pretty big, but most of it is code movement.
Several of these commits are quite new; the history got very messed up
due to a mismerge with the urgent changes for rc8 which completely
broke IA64, and so Ingo requested that we rebase it to straighten it
out."
* 'x86-efi-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
efi: remove "kfree(NULL)"
efi: locking fix in efivar_entry_set_safe()
efi, pstore: Read data from variable store before memcpy()
efi, pstore: Remove entry from list when erasing
efi, pstore: Initialise 'entry' before iterating
efi: split efisubsystem from efivars
efivarfs: Move to fs/efivarfs
efivars: Move pstore code into the new EFI directory
efivars: efivar_entry API
efivars: Keep a private global pointer to efivars
efi: move utf16 string functions to efi.h
x86, efi: Make efi_memblock_x86_reserve_range more readable
efivarfs: convert to use simple_open()
Move the calls to memcpy_fromio() up into the loop in
dmi_scan_machine(), and move the signature checks back down into
dmi_decode(). We need to check at 16-byte intervals but keep a 32-byte
buffer for an SMBIOS entry, so shift the buffer after each iteration.
Merge smbios_present() into dmi_present(), so we look for an SMBIOS
signature at the beginning of the given buffer and then for a DMI
signature at an offset of 16 bytes.
[artem.savkov@gmail.com: use proper buf type in dmi_present()]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Reported-by: Tim McGrath <tmhikaru@gmail.com>
Tested-by: Tim Mcgrath <tmhikaru@gmail.com>
Cc: Zhenzhong Duan <zhenzhong.duan@oracle.com>
Signed-off-by: Artem Savkov <artem.savkov@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
x86 and ia64 can acquire extra hardware identification information
from DMI and print it along with task dumps; however, the usage isn't
consistent.
* x86 show_regs() collects vendor, product and board strings and print
them out with PID, comm and utsname. Some of the information is
printed again later in the same dump.
* warn_slowpath_common() explicitly accesses the DMI board and prints
it out with "Hardware name:" label. This applies to both x86 and
ia64 but is irrelevant on all other archs.
* ia64 doesn't show DMI information on other non-WARN dumps.
This patch introduces arch-specific hardware description used by
dump_stack(). It can be set by calling dump_stack_set_arch_desc()
during boot and, if exists, printed out in a separate line with
"Hardware name:" label.
dmi_set_dump_stack_arch_desc() is added which sets arch-specific
description from DMI data. It uses dmi_ids_string[] which is set from
dmi_present() used for DMI debug message. It is superset of the
information x86 show_regs() is using. The function is called from x86
and ia64 boot code right after dmi_scan_machine().
This makes the explicit DMI handling in warn_slowpath_common()
unnecessary. Removed.
show_regs() isn't yet converted to use generic debug information
printing and this patch doesn't remove the duplicate DMI handling in
x86 show_regs(). The next patch will unify show_regs() handling and
remove the duplication.
An example WARN dump follows.
WARNING: at kernel/workqueue.c:4841 init_workqueues+0x35/0x505()
Modules linked in:
CPU: 0 PID: 1 Comm: swapper/0 Not tainted 3.9.0-rc1-work+ #3
Hardware name: empty empty/S3992, BIOS 080011 10/26/2007
0000000000000009 ffff88007c861e08 ffffffff81c614dc ffff88007c861e48
ffffffff8108f500 ffffffff82228240 0000000000000040 ffffffff8234a08e
0000000000000000 0000000000000000 0000000000000000 ffff88007c861e58
Call Trace:
[<ffffffff81c614dc>] dump_stack+0x19/0x1b
[<ffffffff8108f500>] warn_slowpath_common+0x70/0xa0
[<ffffffff8108f54a>] warn_slowpath_null+0x1a/0x20
[<ffffffff8234a0c3>] init_workqueues+0x35/0x505
...
v2: Use the same string as the debug message from dmi_present() which
also contains BIOS information. Move hardware name into its own
line as warn_slowpath_common() did. This change was suggested by
Bjorn Helgaas.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Fengguang Wu <fengguang.wu@intel.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Jesper Nilsson <jesper.nilsson@axis.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Mike Frysinger <vapier@gentoo.org>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We're goning to use DMI identification for other purposes too. Morph
dmi_dump_ids() which is used to print DMI identification as a debug
message during boot into dmi_format_ids() which formats the same
information sans the leading "DMI:" tag into a string buffer.
dmi_present() is updated to format the information into dmi_ids_string[]
using the new function and print it with "DMI:" prefix.
dmi_ids_string[] will be used for another purpose by a future patch.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Fengguang Wu <fengguang.wu@intel.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Jesper Nilsson <jesper.nilsson@axis.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Mike Frysinger <vapier@gentoo.org>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The intent is that if we aren't allowed to block because we're in an
NMI or an emergency then we only take the lock if it is uncontended.
Part of the problem is the test is reversed so we return -EBUSY if we
acquire the lock.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Seiji reported getting empty dmesg-* files, because the data was never
actually read in efi_pstore_read_func(), and so the memcpy() was copying
garbage data.
This patch necessitated adding __efivar_entry_get() which is callable
between efivar_entry_iter_{begin,end}(). We can also delete
__efivar_entry_size() because efi_pstore_read_func() was the only
caller.
Reported-by: Seiji Aguchi <seiji.aguchi@hds.com>
Tested-by: Seiji Aguchi <seiji.aguchi@hds.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Matthew Garrett <matthew.garrett@nebula.com>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
We need to remove the entry from the EFI variable list before we erase
it from the variable store and free the associated state, otherwise it's
possible to hit the following crash,
BUG: unable to handle kernel NULL pointer dereference at (null)
IP: [<ffffffff8142ea0f>] __efivar_entry_iter+0xcf/0x120
PGD 19483f067 PUD 195426067 PMD 0
Oops: 0000 [#1] SMP
[...]
Call Trace:
[<ffffffff81430ebf>] efi_pstore_erase+0xef/0x140
[<ffffffff81003138>] ? math_error+0x288/0x2d0
[<ffffffff811ea491>] pstore_unlink+0x41/0x60
[<ffffffff811741ff>] vfs_unlink+0x9f/0x110
[<ffffffff8117813b>] do_unlinkat+0x18b/0x280
[<ffffffff8116d7e6>] ? sys_newfstatat+0x36/0x50
[<ffffffff81178472>] sys_unlinkat+0x22/0x40
[<ffffffff81543282>] system_call_fastpath+0x16/0x1b
Reported-by: Seiji Aguchi <seiji.aguchi@hds.com>
Tested-by: Seiji Aguchi <seiji.aguchi@hds.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Matthew Garrett <matthew.garrett@nebula.com>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Seiji reports hitting the following crash when erasing pstore dump
variables,
BUG: unable to handle kernel NULL pointer dereference at 0000000000000fa4
IP: [<ffffffff8142dadf>] __efivar_entry_iter+0x2f/0x120
PGD 18482a067 PUD 190724067 PMD 0
Oops: 0000 [#1] SMP
[...]
Call Trace:
[<ffffffff8143001f>] efi_pstore_erase+0xdf/0x130
[<ffffffff81200038>] ? cap_socket_create+0x8/0x10
[<ffffffff811ea491>] pstore_unlink+0x41/0x60
[<ffffffff811741ff>] vfs_unlink+0x9f/0x110
[<ffffffff8117813b>] do_unlinkat+0x18b/0x280
[<ffffffff81178472>] sys_unlinkat+0x22/0x40
[<ffffffff81542402>] system_call_fastpath+0x16/0x1b
'entry' needs to be initialised in efi_pstore_erase() when iterating
with __efivar_entry_iter(), otherwise the garbage pointer will be
dereferenced, leading to crashes like the above.
Reported-by: Seiji Aguchi <seiji.aguchi@hds.com>
Tested-by: Seiji Aguchi <seiji.aguchi@hds.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Matthew Garrett <matthew.garrett@nebula.com>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
When hot removing memory, a firmware_map_entry which has memory range of
the memory is released by release_firmware_map_entry(). If the entry is
allocated by bootmem, release_firmware_map_entry() adds the entry to
map_entires_bootmem list when firmware_map_find_entry() finds the entry
from map_entries list. But firmware_map_find_entry never find the entry
sicne map_entires list does not have the entry. So the entry just
leaks.
Here are steps of leaking firmware_map_entry:
firmware_map_remove()
-> firmware_map_find_entry()
Find released entry from map_entries list
-> firmware_map_remove_entry()
Delete the entry from map_entries list
-> remove_sysfs_fw_map_entry()
...
-> release_firmware_map_entry()
-> firmware_map_find_entry()
Find the entry from map_entries list but the entry has been
deleted from map_entries list. So the entry is not added
to map_entries_bootmem. Thus the entry leaks
release_firmware_map_entry() should not call firmware_map_find_entry()
since releaed entry has been deleted from map_entries list. So the
patch delete firmware_map_find_entry() from releae_firmware_map_entry()
Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Reviewed-by: Wanpeng Li <liwanp@linux.vnet.ibm.com>
Reviewed-by: Tang Chen <tangchen@cn.fujitsu.com>
Acked-by: Toshi Kani <toshi.kani@hp.com>
Cc: Wen Congyang <wency@cn.fujitsu.com>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
variable_is_present() accesses '__efivars' directly, but when called via
gsmi_init() Michel reports observing the following crash,
BUG: unable to handle kernel NULL pointer dereference at (null)
IP: variable_is_present+0x55/0x170
Call Trace:
register_efivars+0x106/0x370
gsmi_init+0x2ad/0x3da
do_one_initcall+0x3f/0x170
The reason for the crash is that '__efivars' hasn't been initialised nor
has it been registered with register_efivars() by the time the google
EFI SMI driver runs. The gsmi code uses its own struct efivars, and
therefore, a different variable list. Fix the above crash by passing
the registered struct efivars to variable_is_present(), so that we
traverse the correct list.
Reported-by: Michel Lespinasse <walken@google.com>
Tested-by: Michel Lespinasse <walken@google.com>
Cc: Mike Waychison <mikew@google.com>
Cc: Matthew Garrett <matthew.garrett@nebula.com>
Cc: Seiji Aguchi <seiji.aguchi@hds.com>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This registers /sys/firmware/efi/{,systab,efivars/} whenever EFI is enabled
and the system is booted with EFI.
This allows
*) userspace to check for the existence of /sys/firmware/efi as a way
to determine whether or it is running on an EFI system.
*) 'mount -t efivarfs none /sys/firmware/efi/efivars' without manually
loading any modules.
[ Also, move the efivar API into vars.c and unconditionally compile it.
This allows us to move efivars.c, which now only contains the sysfs
variable code, into the firmware/efi directory. Note that the efivars.c
filename is kept to maintain backwards compatability with the old
efivars.ko module. With this patch it is now possible for efivarfs
to be built without CONFIG_EFI_VARS - Matt ]
Cc: Seiji Aguchi <seiji.aguchi@hds.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Mike Waychison <mikew@google.com>
Cc: Kay Sievers <kay@vrfy.org>
Cc: Jeremy Kerr <jk@ozlabs.org>
Cc: Matthew Garrett <mjg59@srcf.ucam.org>
Cc: Chun-Yi Lee <jlee@suse.com>
Cc: Andy Whitcroft <apw@canonical.com>
Cc: Tobias Powalowski <tpowa@archlinux.org>
Signed-off-by: Tom Gundersen <teg@jklm.no>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Now that efivarfs uses the efivar API, move it out of efivars.c and
into fs/efivarfs where it belongs. This move will eventually allow us
to enable the efivarfs code without having to also enable
CONFIG_EFI_VARS built, and vice versa.
Furthermore, things like,
mount -t efivarfs none /sys/firmware/efi/efivars
will now work if efivarfs is built as a module without requiring the
use of MODULE_ALIAS(), which would have been necessary when the
efivarfs code was part of efivars.c.
Cc: Matthew Garrett <matthew.garrett@nebula.com>
Cc: Jeremy Kerr <jk@ozlabs.org>
Reviewed-by: Tom Gundersen <teg@jklm.no>
Tested-by: Tom Gundersen <teg@jklm.no>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
efivars.c has grown far too large and needs to be divided up. Create a
new directory and move the persistence storage code to efi-pstore.c now
that it uses the new efivar API. This helps us to greatly reduce the
size of efivars.c and paves the way for moving other code out of
efivars.c.
Note that because CONFIG_EFI_VARS can be built as a module efi-pstore
must also include support for building as a module.
Reviewed-by: Tom Gundersen <teg@jklm.no>
Tested-by: Tom Gundersen <teg@jklm.no>
Cc: Seiji Aguchi <seiji.aguchi@hds.com>
Cc: Anton Vorontsov <cbouatmailru@gmail.com>
Cc: Colin Cross <ccross@android.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Matthew Garrett <mjg59@srcf.ucam.org>
Cc: Tony Luck <tony.luck@intel.com>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
There isn't really a formal interface for dealing with EFI variables
or struct efivar_entry. Historically, this has led to various bits of
code directly accessing the generic EFI variable ops, which inherently
ties it to specific EFI variable operations instead of indirectly
using whatever ops were registered with register_efivars(). This lead
to the efivarfs code only working with the generic EFI variable ops
and not CONFIG_GOOGLE_SMI.
Encapsulate everything that needs to access '__efivars' inside an
efivar_entry_* API and use the new API in the pstore, sysfs and
efivarfs code.
Much of the efivars code had to be rewritten to use this new API. For
instance, it is now up to the users of the API to build the initial
list of EFI variables in their efivar_init() callback function. The
variable list needs to be passed to efivar_init() which allows us to
keep work arounds for things like implementation bugs in
GetNextVariable() in a central location.
Allowing users of the API to use a callback function to build the list
greatly benefits the efivarfs code which needs to allocate inodes and
dentries for every variable. It previously did this in a racy way
because the code ran without holding the variable spinlock. Both the
sysfs and efivarfs code maintain their own lists which means the two
interfaces can be running simultaneously without interference, though
it should be noted that because no synchronisation is performed it is
very easy to create inconsistencies. efibootmgr doesn't currently use
efivarfs and users are likely to also require the old sysfs interface,
so it makes sense to allow both to be built.
Reviewed-by: Tom Gundersen <teg@jklm.no>
Tested-by: Tom Gundersen <teg@jklm.no>
Cc: Seiji Aguchi <seiji.aguchi@hds.com>
Cc: Matthew Garrett <mjg59@srcf.ucam.org>
Cc: Jeremy Kerr <jk@ozlabs.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Mike Waychison <mikew@google.com>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Some machines have an EFI variable interface that does not conform to
the UEFI specification, e.g. CONFIG_GOOGLE_SMI. Add the necessary code
so that it's only possible to use one implementation of EFI variable
operations at runtime. This allows us to keep a single (file-scope)
global pointer 'struct efivars', which simplifies access. This will
hopefully dissuade developers from accessing the generic operations
struct directly in the future, as was done in the efivarfs and pstore
code, thereby allowing future code to work with both the generic efivar
ops and the google SMI ops.
This may seem like a step backwards in terms of modularity, but we don't
need to track more than one 'struct efivars' at one time. There is no
synchronisation done between multiple EFI variable operations, and
according to Mike no one is using both the generic EFI var ops and
CONFIG_GOOGLE_SMI simultaneously, though a single kernel build _does_
need to able to support both. It also helps to clearly highlight which
functions form the core of the efivars interface - those that require
access to __efivars.
Reviewed-by: Tom Gundersen <teg@jklm.no>
Tested-by: Tom Gundersen <teg@jklm.no>
Acked-by: Mike Waychison <mikew@google.com>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
There are currently two implementations of the utf16 string functions.
Somewhat confusingly, they've got different names.
Centralise the functions in efi.h.
Reviewed-by: Tom Gundersen <teg@jklm.no>
Tested-by: Tom Gundersen <teg@jklm.no>
Reviewed-by: Mike Waychison <mikew@google.com>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
We want to be able to use the utf16 functions that are currently present
in the EFI variables code in platform-specific code as well. Move them to
the kernel core, and in the process rename them to accurately describe what
they do - they don't handle UTF16, only UCS2.
Signed-off-by: Matthew Garrett <matthew.garrett@nebula.com>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Let's not burden ia64 with checks in the common efivars code that we're not
writing too much data to the variable store. That kind of thing is an x86
firmware bug, plain and simple.
efi_query_variable_store() provides platforms with a wrapper in which they can
perform checks and workarounds for EFI variable storage bugs.
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Matthew Garrett <mjg59@srcf.ucam.org>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Some firmware exhibits a bug where the same VariableName and
VendorGuid values are returned on multiple invocations of
GetNextVariableName(). See,
https://bugzilla.kernel.org/show_bug.cgi?id=47631
As a consequence of such a bug, Andre reports hitting the following
WARN_ON() in the sysfs code after updating the BIOS on his, "Gigabyte
Technology Co., Ltd. To be filled by O.E.M./Z77X-UD3H, BIOS F19e
11/21/2012)" machine,
[ 0.581554] EFI Variables Facility v0.08 2004-May-17
[ 0.584914] ------------[ cut here ]------------
[ 0.585639] WARNING: at /home/andre/linux/fs/sysfs/dir.c:536 sysfs_add_one+0xd4/0x100()
[ 0.586381] Hardware name: To be filled by O.E.M.
[ 0.587123] sysfs: cannot create duplicate filename '/firmware/efi/vars/SbAslBufferPtrVar-01f33c25-764d-43ea-aeea-6b5a41f3f3e8'
[ 0.588694] Modules linked in:
[ 0.589484] Pid: 1, comm: swapper/0 Not tainted 3.8.0+ #7
[ 0.590280] Call Trace:
[ 0.591066] [<ffffffff81208954>] ? sysfs_add_one+0xd4/0x100
[ 0.591861] [<ffffffff810587bf>] warn_slowpath_common+0x7f/0xc0
[ 0.592650] [<ffffffff810588bc>] warn_slowpath_fmt+0x4c/0x50
[ 0.593429] [<ffffffff8134dd85>] ? strlcat+0x65/0x80
[ 0.594203] [<ffffffff81208954>] sysfs_add_one+0xd4/0x100
[ 0.594979] [<ffffffff81208b78>] create_dir+0x78/0xd0
[ 0.595753] [<ffffffff81208ec6>] sysfs_create_dir+0x86/0xe0
[ 0.596532] [<ffffffff81347e4c>] kobject_add_internal+0x9c/0x220
[ 0.597310] [<ffffffff81348307>] kobject_init_and_add+0x67/0x90
[ 0.598083] [<ffffffff81584a71>] ? efivar_create_sysfs_entry+0x61/0x1c0
[ 0.598859] [<ffffffff81584b2b>] efivar_create_sysfs_entry+0x11b/0x1c0
[ 0.599631] [<ffffffff8158517e>] register_efivars+0xde/0x420
[ 0.600395] [<ffffffff81d430a7>] ? edd_init+0x2f5/0x2f5
[ 0.601150] [<ffffffff81d4315f>] efivars_init+0xb8/0x104
[ 0.601903] [<ffffffff8100215a>] do_one_initcall+0x12a/0x180
[ 0.602659] [<ffffffff81d05d80>] kernel_init_freeable+0x13e/0x1c6
[ 0.603418] [<ffffffff81d05586>] ? loglevel+0x31/0x31
[ 0.604183] [<ffffffff816a6530>] ? rest_init+0x80/0x80
[ 0.604936] [<ffffffff816a653e>] kernel_init+0xe/0xf0
[ 0.605681] [<ffffffff816ce7ec>] ret_from_fork+0x7c/0xb0
[ 0.606414] [<ffffffff816a6530>] ? rest_init+0x80/0x80
[ 0.607143] ---[ end trace 1609741ab737eb29 ]---
There's not much we can do to work around and keep traversing the
variable list once we hit this firmware bug. Our only solution is to
terminate the loop because, as Lingzhu reports, some machines get
stuck when they encounter duplicate names,
> I had an IBM System x3100 M4 and x3850 X5 on which kernel would
> get stuck in infinite loop creating duplicate sysfs files because,
> for some reason, there are several duplicate boot entries in nvram
> getting GetNextVariableName into a circle of iteration (with
> period > 2).
Also disable the workqueue, as efivar_update_sysfs_entries() uses
GetNextVariableName() to figure out which variables have been created
since the last iteration. That algorithm isn't going to work if
GetNextVariableName() returns duplicates. Note that we don't disable
EFI variable creation completely on the affected machines, it's just
that any pstore dump-* files won't appear in sysfs until the next
boot.
Reported-by: Andre Heider <a.heider@gmail.com>
Reported-by: Lingzhu Xiang <lxiang@redhat.com>
Tested-by: Lingzhu Xiang <lxiang@redhat.com>
Cc: Seiji Aguchi <seiji.aguchi@hds.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
