sched: Enable might_sleep before initializing drivers.

This allows detection of init bugs in built-in drivers.

Signed-off-by: Arve Hjønnevåg <arve@android.com>
Add build option to to set the default panic timeout.
Make /dev/mem configurable, as we don't want it.

Signed-off-by: Brian Swetland <swetland@google.com>
mtd: nand: Allow NAND chip ids to be included standalone.

Lets non-standard NAND drivers take advantage of known NAND
chip information.

Change-Id: I87e2fcb40b07b2ec91e102f1fa7f419a4b4af0a3
Signed-off-by: Dima Zavin <dima@android.com>
mmc_block: Allow more than 8 partitions per card

Set the GENHD_FL_EXT_DEVT flag, which will allocate minor numbers
in major 259 for partitions past disk->minors.

Also remove the use of disk_devt to determine devidx from md->disk.
md->disk->first_minor is always initialized from devidx and can
always be used to recover it.

Signed-off-by: Colin Cross <ccross@android.com>
drivers: power: Add watchdog timer to catch drivers which lockup during suspend.

Rather than hard-lock the kernel, dump the suspend thread stack and
BUG() when a driver takes too long to suspend.  The timeout is set
to 12 seconds to be longer than the usbhid 10 second timeout.

Exclude from the watchdog the time spent waiting for children that
are resumed asynchronously and time every device, whether or not they
resumed synchronously.

Change-Id: Ifd211c06b104860c2fee6eecfe0d61774aa4508a
Original-author: San Mehat <san@google.com>
Signed-off-by: Benoit Goby <benoit@android.com>
[ARM] process: Add display of memory around registers when displaying regs.

This is extremely useful in diagnosing remote crashes, and is based heavily
on original work by <md@google.com>.

Signed-off-by: San Mehat <san@google.com>
Cc: Michael Davidson <md@google.com>

[ARM] process: Use uber-safe probe_kernel_address() to read mem when dumping.

This prevents the dump from taking pagefaults / external aborts.

Signed-off-by: San Mehat <san@google.com>
Revert "genirq: Do not consider disabled wakeup irqs"

This reverts commit 9c6079aa1bfcf7e14de10b824779ce39b679bcb8.
PM: Print pending wakeup IRQ preventing suspend to dmesg

Prints the name of the first action for a pending wakeup IRQ.

Change-Id: I36f90735c75fb7c7ab1084775ec0d0ab02336e6e
Signed-off-by: Todd Poynor <toddpoynor@google.com>
panic: Add board ID to panic output

At times, it is necessary for boards to provide some additional information
as part of panic logs. Provide information on the board hardware as part
of panic logs.

It is safer to print this information at the very end in case something
bad happens as part of the information retrieval itself.

To use this, set global mach_panic_string to an appropriate string in the
board file.

Change-Id: Id12cdda87b0cd2940dd01d52db97e6162f671b4d
Signed-off-by: Nishanth Menon <nm@ti.com>
power: Add option to log time spent in suspend

Prints the time spent in suspend in the kernel log, and
keeps statistics on the time spent in suspend in
/sys/kernel/debug/suspend_time

Change-Id: Ia6b9ebe4baa0f7f5cd211c6a4f7e813aefd3fa1d
Signed-off-by: Colin Cross <ccross@android.com>
Signed-off-by: Todd Poynor <toddpoynor@google.com>
ARM: add option to flush console before reboot

If the console_lock was held while the system was rebooted, the messages
in the temporary logbuffer would not have propogated to all the console
drivers.

This force releases the console lock if it failed to be acquired.

Change-Id: I193dcf7b968be17966833e50b8b8bc70d5d9fe89
Signed-off-by: Dima Zavin <dima@android.com>
cpuidle: governor: menu: don't use loadavg

get_loadavg doesn't work as intended.  According to the comments, it
should be returning an average over a few seconds, but it is actually
reading the instantaneous load.  It is almost always returning 0, but
can sometimes, depending on workload, spike very high into the hundreds
even when the average cpu load is under 10%.  Disable it for now.

Change-Id: I63ed100af1cf9463549939b8113ed83676db5f86
Signed-off-by: Colin Cross <ccross@android.com>
ARM: cache-l2x0: update workaround for PL310 errata 727915

ARM errata 727915 for PL310 has been updated to include a new
workaround required for PL310 r2p0 for l2x0_flush_all, which also
affects l2x0_clean_all in my testing.  For r2p0, clean or flush
each set/way individually.  For r3p0 or greater, use the debug
register for cleaning and flushing.

Requires exporting the cache_id, sets and ways detected in the
init function for later use.

Change-Id: I215055cbe5dc7e4e8184fb2befc4aff672ef0a12
Signed-off-by: Colin Cross <ccross@android.com>
ARM: smp: implement arch_trigger_all_cpus_backtrace using IPI

Based on a rough patch by frank.rowand@am.sony.com

Since ARM doesn't have an NMI (fiq's are not always available),
send an IPI to all other CPUs (current cpu prints the stack directly)
to capture a backtrace.

Change-Id: I8b163c8cec05d521b433ae133795865e8a33d4e2
Signed-off-by: Dima Zavin <dima@android.com>
ARM: allow the kernel text section to be made read-only

This patch implements CONFIG_DEBUG_RODATA, allowing
the kernel text section to be marked read-only in
order to catch bugs that write over the kernel.  This
requires mapping the kernel code, plus up to 4MB, using
pages instead of sections, which can increase TLB
pressure.

The kernel is normally mapped using 1MB section entries
in the first level page table, and the first level page
table is copied into every mm.  This prevents marking
the kernel text read-only, because the 1MB section
entries are too large granularity to separate the init
section, which is reused as read-write memory after
init, and the kernel text section.  Also, the top level
page table for every process would need to be updated,
which is not possible to do safely and efficiently on SMP.

To solve both problems, allow alloc_init_pte to overwrite
an existing section entry with a fully-populated second
level page table.  When CONFIG_DEBUG_RODATA is set, all
the section entries that overlap the kernel text section
will be replaced with page mappings.  The kernel always
uses a pair of 2MB-aligned 1MB sections, so up to 2MB
of memory before and after the kernel may end up page
mapped.

When the top level page tables are copied into each
process the second level page tables are not copied,
leaving a single second level page table that will
affect all processes on all cpus.  To mark a page
read-only, the second level page table is located using
the pointer in the first level page table for the
current process, and the supervisor RO bit is flipped
atomically.  Once all pages have been updated, all TLBs
are flushed to ensure the changes are visible on all
cpus.

If CONFIG_DEBUG_RODATA is not set, the kernel will be
mapped using the normal 1MB section entries.

Change-Id: I94fae337f882c2e123abaf8e1082c29cd5d483c6
Signed-off-by: Colin Cross <ccross@android.com>
cgroup: Add generic cgroup subsystem permission checks

Rather than using explicit euid == 0 checks when trying to move
tasks into a cgroup via CFS, move permission checks into each
specific cgroup subsystem. If a subsystem does not specify a
'allow_attach' handler, then we fall back to doing our checks
the old way.

Use the 'allow_attach' handler for the 'cpu' cgroup to allow
non-root processes to add arbitrary processes to a 'cpu' cgroup
if it has the CAP_SYS_NICE capability set.

This version of the patch adds a 'allow_attach' handler instead
of reusing the 'can_attach' handler.  If the 'can_attach' handler
is reused, a new cgroup that implements 'can_attach' but not
the permission checks could end up with no permission checks
at all.

Change-Id: Icfa950aa9321d1ceba362061d32dc7dfa2c64f0c
Original-Author: San Mehat <san@google.com>
Signed-off-by: Colin Cross <ccross@android.com>
ARM: Make low-level printk work

Makes low-level printk work.

Signed-off-by: Tony Lindgren <tony@atomide.com>
[ARM] armv6 dcc tty driver

Signed-off-by: Brian Swetland <swetland@google.com>
Signed-off-by: Arve Hjønnevåg <arve@android.com>
[ARM] avoid mis-detecting some V7 cores in the decompressor

This allows kernel decompress to happen nearly instantly instead
of taking over 20 seconds.

Signed-off-by: Brian Swetland <swetland@google.com>