This adds:
alias: devname:<name>
to some common kernel modules, which will allow the on-demand loading
of the kernel module when the device node is accessed.
Ideally all these modules would be compiled-in, but distros seems too
much in love with their modularization that we need to cover the common
cases with this new facility. It will allow us to remove a bunch of pretty
useless init scripts and modprobes from init scripts.
The static device node aliases will be carried in the module itself. The
program depmod will extract this information to a file in the module directory:
$ cat /lib/modules/2.6.34-00650-g537b60d-dirty/modules.devname
# Device nodes to trigger on-demand module loading.
microcode cpu/microcode c10:184
fuse fuse c10:229
ppp_generic ppp c108:0
tun net/tun c10:200
dm_mod mapper/control c10:235
Udev will pick up the depmod created file on startup and create all the
static device nodes which the kernel modules specify, so that these modules
get automatically loaded when the device node is accessed:
$ /sbin/udevd --debug
...
static_dev_create_from_modules: mknod '/dev/cpu/microcode' c10:184
static_dev_create_from_modules: mknod '/dev/fuse' c10:229
static_dev_create_from_modules: mknod '/dev/ppp' c108:0
static_dev_create_from_modules: mknod '/dev/net/tun' c10:200
static_dev_create_from_modules: mknod '/dev/mapper/control' c10:235
udev_rules_apply_static_dev_perms: chmod '/dev/net/tun' 0666
udev_rules_apply_static_dev_perms: chmod '/dev/fuse' 0666
A few device nodes are switched to statically allocated numbers, to allow
the static nodes to work. This might also useful for systems which still run
a plain static /dev, which is completely unsafe to use with any dynamic minor
numbers.
Note:
The devname aliases must be limited to the *common* and *single*instance*
device nodes, like the misc devices, and never be used for conceptually limited
systems like the loop devices, which should rather get fixed properly and get a
control node for losetup to talk to, instead of creating a random number of
device nodes in advance, regardless if they are ever used.
This facility is to hide the mess distros are creating with too modualized
kernels, and just to hide that these modules are not compiled-in, and not to
paper-over broken concepts. Thanks! :)
Cc: Greg Kroah-Hartman <gregkh@suse.de>
Cc: David S. Miller <davem@davemloft.net>
Cc: Miklos Szeredi <miklos@szeredi.hu>
Cc: Chris Mason <chris.mason@oracle.com>
Cc: Alasdair G Kergon <agk@redhat.com>
Cc: Tigran Aivazian <tigran@aivazian.fsnet.co.uk>
Cc: Ian Kent <raven@themaw.net>
Signed-Off-By: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
No need to seek on this file, so prevent it outright so we can
avoid using default_llseek - removes one more BKL usage.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
[drop useless llseek = no_llseek and smp_lock.h inclusion]
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Arnd Bergmann <arnd@relay.de.ibm.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Dmitry Adamushko <dmitry.adamushko@gmail.com>
LKML-Reference: <1270910781-8786-1-git-send-regression-fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Commit d1c84f79a6
leads to a regression when microcode_amd.c is compiled into the kernel.
It causes a big boot delay because the firmware is not available.
See http://marc.info/?l=linux-kernel&m=126267290920060
It also renders the reload sysfs attribute useless.
Fixing this is too intrusive for an -rc5 kernel.
Thus I'd like to restore the microcode loading behaviour of kernel
2.6.32.
CC: Gene Heskett <gene.heskett@verizon.net>
Signed-off-by: Andreas Herrmann <andreas.herrmann3@amd.com>
LKML-Reference: <20100122203456.GB13792@alberich.amd.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
This reverts commit 9f15226e75. It's just
wrong, and broke resume for Rafael even on a non-AMD CPU.
As Rafael says:
"... it causes microcode_init_cpu() to be called during resume even for
CPUs for which there's no microcode to apply. That, in turn, results
in executing request_firmware() (on Intel CPUs at least) which doesn't
work at this stage of resume (we have device interrupts disabled, I/O
devices are still suspended and so on).
If I'm not mistaken, the "if (uci->valid)" logic means "if that CPU is
known to us" , so before commit 9f15226e75 microcode_resume_cpu() was
called for all CPUs already in the system during suspend, which was
the right thing to do. The commit changed it so that the CPUs without
microcode to apply are now treated as "unknown", which is not quite
right.
The problem this commit attempted to solve has to be handled
differently."
Bisected-and -requested-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
- Use #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
- Remove "microcode: " prefix from each pr_<level>
- Fix duplicated KERN_ERR prefix
- Coalesce pr_<level> format strings
- Add a space after an exclamation point
No other change in output.
Signed-off-by: Joe Perches <joe@perches.com>
Cc: Andy Whitcroft <apw@canonical.com>
Cc: Andreas Herrmann <herrmann.der.user@googlemail.com>
LKML-Reference: <1260340250.27677.191.camel@Joe-Laptop.home>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
* 'x86-microcode-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
x86: ucode-amd: Move family check to microcde_amd.c's init function
x86, ucode-amd: Ensure ucode update on suspend/resume after CPU off/online cycle
x86: ucode-amd: Convert printk(KERN_*...) to pr_*(...)
x86: ucode-amd: Don't warn when no ucode is available for a CPU revision
x86: ucode-amd: Load ucode-patches once and not separately of each CPU
x86, amd-ucode: Remove needless log messages
When switching a CPU offline/online and then doing
suspend/resume, ucode is not updated on this CPU.
This is due to the microcode_fini_cpu() call which frees uci->mc
when setting the CPU offline:
static void microcode_fini_cpu_amd(int cpu)
{
struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
vfree(uci->mc);
uci->mc = NULL;
}
When the CPU is set online uci->mc is still NULL because no
ucode update is required.
Finally this prevents ucode update when resuming after suspend:
static enum ucode_state microcode_resume_cpu(int cpu)
{
struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
if (!uci->mc)
return UCODE_NFOUND;
...
}
Fix is to check whether uci->mc is valid before
microcode_resume_cpu() is called.
Signed-off-by: Andreas Herrmann <andreas.herrmann3@amd.com>
Cc: dimm <dmitry.adamushko@gmail.com>
LKML-Reference: <20091111190329.GF18592@alberich.amd.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This also implies that corresponding log messages, e.g.
platform microcode: firmware: requesting amd-ucode/microcode_amd.bin
show up only once on module load and not when ucode is updated
for each CPU.
Signed-off-by: Andreas Herrmann <andreas.herrmann3@amd.com>
Cc: dimm <dmitry.adamushko@gmail.com>
LKML-Reference: <20091110110723.GH30802@alberich.amd.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
cycle_lock_kernel() in microcode_open() is a worthless exercise as
there is nothing to wait for. Remove it.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
LKML-Reference: <20091010153349.196074920@linutronix.de>
Sizing of memory allocations shouldn't depend on the number of physical
pages found in a system, as that generally includes (perhaps a huge amount
of) non-RAM pages. The amount of what actually is usable as storage
should instead be used as a basis here.
Some of the calculations (i.e. those not intending to use high memory)
should likely even use (totalram_pages - totalhigh_pages).
Signed-off-by: Jan Beulich <jbeulich@novell.com>
Acked-by: Rusty Russell <rusty@rustcorp.com.au>
Acked-by: Ingo Molnar <mingo@elte.hu>
Cc: Dave Airlie <airlied@linux.ie>
Cc: Kyle McMartin <kyle@mcmartin.ca>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: Hugh Dickins <hugh.dickins@tiscali.co.uk>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Patrick McHardy <kaber@trash.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This allows subsytems to provide devtmpfs with non-default permissions
for the device node. Instead of the default mode of 0600, null, zero,
random, urandom, full, tty, ptmx now have a mode of 0666, which allows
non-privileged processes to access standard device nodes in case no
other userspace process applies the expected permissions.
This also fixes a wrong assignment in pktcdvd and a checkpatch.pl complain.
Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This adds support for misc devices to report their requested nodename to
userspace. It also updates a number of misc drivers to provide the
needed subdirectory and device name to be used for them.
Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Jan Blunck <jblunck@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* Solve issues described in 6f66cbc630
in a way that doesn't resort to set_cpus_allowed();
* in fact, only collect_cpu_info and apply_microcode callbacks
must run on a target cpu, others will do just fine on any other.
smp_call_function_single() (as suggested by Ingo) is used to run
these callbacks on a target cpu.
* cleanup of synchronization logic of the 'microcode_core' part
The generic 'microcode_core' part guarantees that only a single cpu
(be it a full-fledged cpu, one of the cores or HT)
is being updated at any particular moment of time.
In general, there is no need for any additional sync. mechanism in
arch-specific parts (the patch removes existing spinlocks).
See also the "Synchronization" section in microcode_core.c.
* return -EINVAL instead of -1 (which is translated into -EPERM) in
microcode_write(), reload_cpu() and mc_sysdev_add(). Other suggestions
for an error code?
* use 'enum ucode_state' as return value of request_microcode_{fw, user}
to gain more flexibility by distinguishing between real error cases
and situations when an appropriate ucode was not found (which is not an
error per-se).
* some minor cleanups
Thanks a lot to Hugh Dickins for review/suggestions/testing!
Reference: http://marc.info/?l=linux-kernel&m=124025889012541&w=2
[ Impact: refactor and clean up microcode driver locking code ]
Signed-off-by: Dmitry Adamushko <dmitry.adamushko@gmail.com>
Acked-by: Hugh Dickins <hugh@veritas.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Andreas Herrmann <andreas.herrmann3@amd.com>
Cc: Peter Oruba <peter.oruba@amd.com>
Cc: Arjan van de Ven <arjan@infradead.org>
LKML-Reference: <1242078507.5560.9.camel@earth>
[ did some more cleanups ]
Signed-off-by: Ingo Molnar <mingo@elte.hu>
arch/x86/include/asm/microcode.h | 25 ++
arch/x86/kernel/microcode_amd.c | 58 ++----
arch/x86/kernel/microcode_core.c | 326 +++++++++++++++++++++-----------------
arch/x86/kernel/microcode_intel.c | 92 +++-------
4 files changed, 261 insertions(+), 240 deletions(-)
(~20 new comment lines)
* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
x86: fix microcode driver newly spewing warnings
x86, PAT: Remove page granularity tracking for vm_insert_pfn maps
x86: disable X86_PTRACE_BTS for now
x86, documentation: kernel-parameters replace X86-32,X86-64 with X86
x86: pci-swiotlb.c swiotlb_dma_ops should be static
x86, PAT: Remove duplicate memtype reserve in devmem mmap
x86, PAT: Consolidate code in pat_x_mtrr_type() and reserve_memtype()
x86, PAT: Changing memtype to WC ensuring no WB alias
x86, PAT: Handle faults cleanly in set_memory_ APIs
x86, PAT: Change order of cpa and free in set_memory_wb
x86, CPA: Change idmap attribute before ioremap attribute setup
Jeff Garzik reported this WARN_ON() noise:
> Kernel: 2.6.30-rc1-00306-g8371f87
> Hardware: ICH10 x86-64
>
> This is a regression from 2.6.29. Microcode spews the following WARNING
> multiple times during boot:
>
> ------------[ cut here ]------------
> WARNING: at fs/sysfs/group.c:138 sysfs_remove_group+0xeb/0xf0()
> Hardware name: sysfs group ffffffffa0209700 not found for
> kobject 'cpu0'
Keep sysfs files around for cpus even when we failed to locate
microcode for them at the moment of module loading. The appropriate
microcode firmware can become available later on.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Revert part of af5c820a31 ("x86: cpumask:
use work_on_cpu in arch/x86/kernel/microcode_core.c")
That change is causing only one Intel CPU's microcode to be updated e.g.
microcode: CPU3 updated from revision 0x9 to 0x17, date = 2005-04-22
where before it announced that also for CPU0 and CPU1 and CPU2.
We cannot use work_on_cpu() in the CONFIG_MICROCODE_OLD_INTERFACE code,
because Intel's request_microcode_user() involves a copy_from_user() from
/sbin/microcode_ctl, which therefore needs to be on that CPU at the time.
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Impact: don't play with current's cpumask
Straightforward indirection through work_on_cpu(). One change is
that the error code from microcode_update_cpu() is now actually
plumbed back to microcode_init_cpu(), so now we printk if it fails
on cpu hotplug.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Dmitry Adamushko <dmitry.adamushko@gmail.com>
Cc: Peter Oruba <peter.oruba@amd.com>
LKML-Reference: <200903111632.37279.rusty@rustcorp.com.au>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: fix deadlock
This is in response to the following bug report:
Bug-Entry : http://bugzilla.kernel.org/show_bug.cgi?id=12100
Subject : resume (S2R) broken by Intel microcode module, on A110L
Submitter : Andreas Mohr <andi@lisas.de>
Date : 2008-11-25 08:48 (19 days old)
Handled-By : Dmitry Adamushko <dmitry.adamushko@gmail.com>
[ The deadlock scenario has been discovered by Andreas Mohr ]
I think I might have a logical explanation why the system:
(http://bugzilla.kernel.org/show_bug.cgi?id=12100)
might hang upon resuming, OTOH it should have likely hanged each and every time.
(1) possible deadlock in microcode_resume_cpu() if either 'if' section is
taken;
(2) now, I don't see it in spec. and can't experimentally verify it (newer
ucodes don't seem to be available for my Core2duo)... but logically-wise, I'd
think that when read upon resuming, the 'microcode revision' (MSR 0x8B) should
be back to its original one (we need to reload ucode anyway so it doesn't seem
logical if a cpu doesn't drop the version)... if so, the comparison with
memcmp() for the full 'struct cpu_signature' is wrong... and that's how one of
the aforementioned 'if' sections might have been triggered - leading to a
deadlock.
Obviously, in my tests I simulated loading/resuming with the ucode of the same
version (just to see that the file is loaded/re-loaded upon resuming) so this
issue has never popped up.
I'd appreciate if someone with an appropriate system might give a try to the
2nd patch (titled "fix a comparison && deadlock...").
In any case, the deadlock situation is a must-have fix.
Reported-by: Andreas Mohr <andi@lisas.de>
Signed-off-by: Dmitry Adamushko <dmitry.adamushko@gmail.com>
Tested-by: Andreas Mohr <andi@lisas.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: <stable@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: make global variables and a function static
Fix following sparse warnings:
arch/x86/kernel/microcode_core.c:102:22: warning: symbol
'microcode_ops' was not declared. Should it be static?
arch/x86/kernel/microcode_core.c:206:24: warning: symbol
'microcode_pdev' was not declared. Should it be static?
arch/x86/kernel/microcode_core.c:322:6: warning: symbol
'microcode_update_cpu' was not declared. Should it be static?
arch/x86/kernel/microcode_intel.c:468:22: warning: symbol
'microcode_intel_ops' was not declared. Should it be static?
Signed-off-by: Hannes Eder <hannes@hanneseder.net>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Combine both generic and arch-specific parts of microcode into a
single module (arch-specific parts are config-dependent).
Also while we are at it, move arch-specific parts from microcode.h
into their respective arch-specific .c files.
Signed-off-by: Dmitry Adamushko <dmitry.adamushko@gmail.com>
Cc: "Peter Oruba" <peter.oruba@amd.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>