The __cpuinit type of throwaway sections might have made sense
some time ago when RAM was more constrained, but now the savings
do not offset the cost and complications. For example, the fix in
commit 5e427ec2d0 ("x86: Fix bit corruption at CPU resume time")
is a good example of the nasty type of bugs that can be created
with improper use of the various __init prefixes.
After a discussion on LKML[1] it was decided that cpuinit should go
the way of devinit and be phased out. Once all the users are gone,
we can then finally remove the macros themselves from linux/init.h.
Note that some harmless section mismatch warnings may result, since
notify_cpu_starting() and cpu_up() are arch independent (kernel/cpu.c)
are flagged as __cpuinit -- so if we remove the __cpuinit from
arch specific callers, we will also get section mismatch warnings.
As an intermediate step, we intend to turn the linux/init.h cpuinit
content into no-ops as early as possible, since that will get rid
of these warnings. In any case, they are temporary and harmless.
This removes all the arch/x86 uses of the __cpuinit macros from
all C files. x86 only had the one __CPUINIT used in assembly files,
and it wasn't paired off with a .previous or a __FINIT, so we can
delete it directly w/o any corresponding additional change there.
[1] https://lkml.org/lkml/2013/5/20/589
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: x86@kernel.org
Acked-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: H. Peter Anvin <hpa@linux.intel.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Currently save_microcode_in_initrd() is declared in vendor neutural
microcode.h file, but defined in vendor specific
microcode_intel_early.c file. Vendor abstract it out to
microcode_core_early.c with a wrapper function.
Signed-off-by: Jacob Shin <jacob.shin@amd.com>
Link: http://lkml.kernel.org/r/1369940959-2077-3-git-send-email-jacob.shin@amd.com
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
This can easily be triggered if a new CPU is added (via
ACPI hotplug mechanism) and from user-space you do:
echo 1 > /sys/devices/system/cpu/cpu3/online
(or wait for UDEV to do it) on a newly appeared physical CPU.
The deadlock is that the "store_online" in drivers/base/cpu.c
takes the cpu_hotplug_driver_lock() lock, then calls "cpu_up".
"cpu_up" eventually ends up calling "save_mc_for_early"
which also takes the cpu_hotplug_driver_lock() lock.
And here is that lockdep thinks of it:
smpboot: Stack at about ffff880075c39f44
smpboot: CPU3: has booted.
microcode: CPU3 sig=0x206a7, pf=0x2, revision=0x25
=============================================
[ INFO: possible recursive locking detected ]
3.9.0upstream-10129-g167af0e #1 Not tainted
---------------------------------------------
sh/2487 is trying to acquire lock:
(x86_cpu_hotplug_driver_mutex){+.+.+.}, at: [<ffffffff81075512>] cpu_hotplug_driver_lock+0x12/0x20
but task is already holding lock:
(x86_cpu_hotplug_driver_mutex){+.+.+.}, at: [<ffffffff81075512>] cpu_hotplug_driver_lock+0x12/0x20
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0
----
lock(x86_cpu_hotplug_driver_mutex);
lock(x86_cpu_hotplug_driver_mutex);
*** DEADLOCK ***
May be due to missing lock nesting notation
6 locks held by sh/2487:
#0: (sb_writers#5){.+.+.+}, at: [<ffffffff811ca48d>] vfs_write+0x17d/0x190
#1: (&buffer->mutex){+.+.+.}, at: [<ffffffff812464ef>] sysfs_write_file+0x3f/0x160
#2: (s_active#20){.+.+.+}, at: [<ffffffff81246578>] sysfs_write_file+0xc8/0x160
#3: (x86_cpu_hotplug_driver_mutex){+.+.+.}, at: [<ffffffff81075512>] cpu_hotplug_driver_lock+0x12/0x20
#4: (cpu_add_remove_lock){+.+.+.}, at: [<ffffffff810961c2>] cpu_maps_update_begin+0x12/0x20
#5: (cpu_hotplug.lock){+.+.+.}, at: [<ffffffff810962a7>] cpu_hotplug_begin+0x27/0x60
Suggested-and-Acked-by: Borislav Petkov <bp@alien8.de>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: fenghua.yu@intel.com
Cc: xen-devel@lists.xensource.com
Cc: stable@vger.kernel.org # for v3.9
Link: http://lkml.kernel.org/r/1368029583-23337-1-git-send-email-konrad.wilk@oracle.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
In 32-bit, __pa_symbol() in CONFIG_DEBUG_VIRTUAL accesses kernel data
(e.g. max_low_pfn) that not only hasn't been setup yet in such early
boot phase, but since we are in linear mode, cannot even be detected
as uninitialized.
Thus, use __pa_nodebug() rather than __pa_symbol() to get a global
symbol's physical address.
Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Link: http://lkml.kernel.org/r/1363705484-27645-1-git-send-email-fenghua.yu@intel.com
Reported-and-tested-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Implementation of early update ucode on Intel's CPU.
load_ucode_intel_bsp() scans ucode in initrd image file which is a cpio format
ucode followed by ordinary initrd image file. The binary ucode file is stored
in kernel/x86/microcode/GenuineIntel.bin in the cpio data. All ucode
patches with the same model as BSP are saved in memory. A matching ucode patch
is updated on BSP.
load_ucode_intel_ap() reads saved ucoded patches and updates ucode on AP.
Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Link: http://lkml.kernel.org/r/1356075872-3054-9-git-send-email-fenghua.yu@intel.com
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Paul Gortmaker
Jacob Shin
Borislav Petkov
Konrad Rzeszutek Wilk
H. Peter Anvin
Fenghua Yu