user/sven/linux.git/init, branch v3.2.38

efi: Make 'efi_enabled' a function to query EFI facilities

2013-02-06T04:33:50Z

commit 83e68189745ad931c2afd45d8ee3303929233e7f upstream. Originally 'efi_enabled' indicated whether a kernel was booted from EFI firmware. Over time its semantics have changed, and it now indicates whether or not we are booted on an EFI machine with bit-native firmware, e.g. 64-bit kernel with 64-bit firmware. The immediate motivation for this patch is the bug report at, https://bugs.launchpad.net/ubuntu-cdimage/+bug/1040557 which details how running a platform driver on an EFI machine that is designed to run under BIOS can cause the machine to become bricked. Also, the following report, https://bugzilla.kernel.org/show_bug.cgi?id=47121 details how running said driver can also cause Machine Check Exceptions. Drivers need a new means of detecting whether they're running on an EFI machine, as sadly the expression, if (!efi_enabled) hasn't been a sufficient condition for quite some time. Users actually want to query 'efi_enabled' for different reasons - what they really want access to is the list of available EFI facilities. For instance, the x86 reboot code needs to know whether it can invoke the ResetSystem() function provided by the EFI runtime services, while the ACPI OSL code wants to know whether the EFI config tables were mapped successfully. There are also checks in some of the platform driver code to simply see if they're running on an EFI machine (which would make it a bad idea to do BIOS-y things). This patch is a prereq for the samsung-laptop fix patch. Cc: David Airlie Cc: Corentin Chary Cc: Matthew Garrett Cc: Dave Jiang Cc: Olof Johansson Cc: Peter Jones Cc: Colin Ian King Cc: Steve Langasek Cc: Tony Luck Cc: Konrad Rzeszutek Wilk Cc: Rafael J. Wysocki Signed-off-by: Matt Fleming Signed-off-by: H. Peter Anvin [bwh: Backported to 3.2: - Adjust context (a lot) - Add efi_is_native() function from commit 5189c2a7c776 ('x86: efi: Turn off efi_enabled after setup on mixed fw/kernel') - Make efi_init() bail out when booted non-native, as it would previously not be called in this case - Drop inapplicable changes to start_kernel()] Signed-off-by: Ben Hutchings

init: don't try mounting device as nfs root unless type fully matches

2012-05-30T23:43:50Z

commit 377485f6244af255b04d662cf19cddbbc4ae4310 upstream. Currently, we'll try mounting any device who's major device number is UNNAMED_MAJOR as NFS root. This would happen for non-NFS devices as well (such as 9p devices) but it wouldn't cause any issues since mounting the device as NFS would fail quickly and the code proceeded to doing the proper mount: [ 101.522716] VFS: Unable to mount root fs via NFS, trying floppy. [ 101.534499] VFS: Mounted root (9p filesystem) on device 0:18. Commit 6829a048102a ("NFS: Retry mounting NFSROOT") introduced retries when mounting NFS root, which means that now we don't immediately fail and instead it takes an additional 90+ seconds until we stop retrying, which has revealed the issue this patch fixes. This meant that it would take an additional 90 seconds to boot when we're not using a device type which gets detected in order before NFS. This patch modifies the NFS type check to require device type to be 'Root_NFS' instead of requiring the device to have an UNNAMED_MAJOR major. This makes boot process cleaner since we now won't go through the NFS mounting code at all when the device isn't an NFS root ("/dev/nfs"). Signed-off-by: Sasha Levin Signed-off-by: Linus Torvalds Signed-off-by: Ben Hutchings

Fix blocking allocations called very early during bootup

2012-05-30T23:43:29Z

commit 31a67102f4762df5544bc2dfb34a931233d2a5b2 upstream. During early boot, when the scheduler hasn't really been fully set up, we really can't do blocking allocations because with certain (dubious) configurations the "might_resched()" calls can actually result in scheduling events. We could just make such users always use GFP_ATOMIC, but quite often the code that does the allocation isn't really aware of the fact that the scheduler isn't up yet, and forcing that kind of random knowledge on the initialization code is just annoying and not good for anybody. And we actually have a the 'gfp_allowed_mask' exactly for this reason: it's just that the kernel init sequence happens to set it to allow blocking allocations much too early. So move the 'gfp_allowed_mask' initialization from 'start_kernel()' (which is some of the earliest init code, and runs with preemption disabled for good reasons) into 'kernel_init()'. kernel_init() is run in the newly created thread that will become the 'init' process, as opposed to the early startup code that runs within the context of what will be the first idle thread. So by the time we reach 'kernel_init()', we know that the scheduler must be at least limping along, because we've already scheduled from the idle thread into the init thread. Reported-by: Steven Rostedt Cc: David Rientjes Signed-off-by: Linus Torvalds Signed-off-by: Ben Hutchings

NFS: Retry mounting NFSROOT

2012-01-26T00:13:14Z

commit 43717c7daebf10b43f12e68512484b3095bb1ba5 upstream. Lukas Razik reports that on his SPARC system, booting with an NFS root file system stopped working after commit 56463e50 "NFS: Use super.c for NFSROOT mount option parsing." We found that the network switch to which Lukas' client was attached was delaying access to the LAN after the client's NIC driver reported that its link was up. The delay was longer than the timeouts used in the NFS client during mounting. NFSROOT worked for Lukas before commit 56463e50 because in those kernels, the client's first operation was an rpcbind request to determine which port the NFS server was listening on. When that request failed after a long timeout, the client simply selected the default NFS port (2049). By that time the switch was allowing access to the LAN, and the mount succeeded. Neither of these client behaviors is desirable, so reverting 56463e50 is really not a choice. Instead, introduce a mechanism that retries the NFSROOT mount request several times. This is the same tactic that normal user space NFS mounts employ to overcome server and network delays. Signed-off-by: Lukas Razik [ cel: match kernel coding style, add proper patch description ] [ cel: add exponential back-off ] Signed-off-by: Chuck Lever Tested-by: Lukas Razik Signed-off-by: Trond Myklebust Signed-off-by: Greg Kroah-Hartman

Merge branch 'upstream/jump-label-noearly' of git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen

2011-11-07T04:20:46Z

* 'upstream/jump-label-noearly' of git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen: jump-label: initialize jump-label subsystem much earlier x86/jump_label: add arch_jump_label_transform_static() s390/jump-label: add arch_jump_label_transform_static() jump_label: add arch_jump_label_transform_static() to optimise non-live code updates sparc/jump_label: drop arch_jump_label_text_poke_early() x86/jump_label: drop arch_jump_label_text_poke_early() jump_label: if a key has already been initialized, don't nop it out stop_machine: make stop_machine safe and efficient to call early jump_label: use proper atomic_t initializer Conflicts: - arch/x86/kernel/jump_label.c Added __init_or_module to arch_jump_label_text_poke_early vs removal of that function entirely - kernel/stop_machine.c same patch ("stop_machine: make stop_machine safe and efficient to call early") merged twice, with whitespace fix in one version

sysctl: make CONFIG_SYSCTL_SYSCALL default to n

2011-11-02T23:07:02Z

When I tried to send a patch to remove it, Andi told me we still need to keep compabitlies for old libc, so we can't remove this completely. Then just make it default to n and remove the doc from feature-removal-schedule.txt. Signed-off-by: WANG Cong Cc: Eric Biederman Cc: Andi Kleen Cc: Alexey Dobriyan Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

init: add root=PARTUUID=UUID/PARTNROFF=%d support

2011-11-02T23:07:01Z

Expand root=PARTUUID=UUID syntax to support selecting a root partition by integer offset from a known, unique partition. This approach provides similar properties to specifying a device and partition number, but using the UUID as the unique path prior to evaluating the offset. For example, root=PARTUUID=99DE9194-FC15-4223-9192-FC243948F88B/PARTNROFF=1 selects the partition with UUID 99DE.. then select the next partition. This change is motivated by a particular usecase in Chromium OS where the bootloader can easily determine what partition it is on (by UUID) but doesn't perform general partition table walking. That said, support for this model provides a direct mechanism for the user to modify the root partition to boot without specifically needing to extract each UUID or update the bootloader explicitly when the root partition UUID is changed (if it is recreated to be larger, for instance). Pinning to a /boot-style partition UUID allows the arbitrary root partition reconfiguration/modifications with slightly less ambiguity than just [dev][partition] and less stringency than the specific root partition UUID. [sfr@canb.auug.org.au: fix init sections warning] Signed-off-by: Will Drewry Cc: Kay Sievers Cc: Randy Dunlap Cc: Namhyung Kim Cc: Trond Myklebust Cc: Jens Axboe Signed-off-by: Stephen Rothwell Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

init/do_mounts_rd.c: fix ramdisk identification for padded cramfs

2011-11-02T23:06:58Z

When a cramfs ramdisk padded with 512 bytes is given to the kernel, the current identify_ramdisk_image function fails to identify it. Tested with a padded cramfs image on an ARM based board. Signed-off-by: Neil Armstrong Cc: Namhyung Kim Cc: Davidlohr Bueso Cc: Al Viro Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2011-10-26T15:08:43Z

* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (46 commits) llist: Add back llist_add_batch() and llist_del_first() prototypes sched: Don't use tasklist_lock for debug prints sched: Warn on rt throttling sched: Unify the ->cpus_allowed mask copy sched: Wrap scheduler p->cpus_allowed access sched: Request for idle balance during nohz idle load balance sched: Use resched IPI to kick off the nohz idle balance sched: Fix idle_cpu() llist: Remove cpu_relax() usage in cmpxchg loops sched: Convert to struct llist llist: Add llist_next() irq_work: Use llist in the struct irq_work logic llist: Return whether list is empty before adding in llist_add() llist: Move cpu_relax() to after the cmpxchg() llist: Remove the platform-dependent NMI checks llist: Make some llist functions inline sched, tracing: Show PREEMPT_ACTIVE state in trace_sched_switch sched: Remove redundant test in check_preempt_tick() sched: Add documentation for bandwidth control sched: Return unused runtime on group dequeue ...

Merge branch 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2011-10-26T14:26:53Z

* 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (45 commits) rcu: Move propagation of ->completed from rcu_start_gp() to rcu_report_qs_rsp() rcu: Remove rcu_needs_cpu_flush() to avoid false quiescent states rcu: Wire up RCU_BOOST_PRIO for rcutree rcu: Make rcu_torture_boost() exit loops at end of test rcu: Make rcu_torture_fqs() exit loops at end of test rcu: Permit rt_mutex_unlock() with irqs disabled rcu: Avoid having just-onlined CPU resched itself when RCU is idle rcu: Suppress NMI backtraces when stall ends before dump rcu: Prohibit grace periods during early boot rcu: Simplify unboosting checks rcu: Prevent early boot set_need_resched() from __rcu_pending() rcu: Dump local stack if cannot dump all CPUs' stacks rcu: Move __rcu_read_unlock()'s barrier() within if-statement rcu: Improve rcu_assign_pointer() and RCU_INIT_POINTER() documentation rcu: Make rcu_assign_pointer() unconditionally insert a memory barrier rcu: Make rcu_implicit_dynticks_qs() locals be correct size rcu: Eliminate in_irq() checks in rcu_enter_nohz() nohz: Remove nohz_cpu_mask rcu: Document interpretation of RCU-lockdep splats rcu: Allow rcutorture's stat_interval parameter to be changed at runtime ...