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2008-06-23Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound-2.6 * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound-2.6: ALSA: sb - Fix wrong assertions ALSA: aw2 - Fix Oops at initialization
2008-06-23mm: fix race in COW logicNick Piggin
There is a race in the COW logic. It contains a shortcut to avoid the COW and reuse the page if we have the sole reference on the page, however it is possible to have two racing do_wp_page()ers with one causing the other to mistakenly believe it is safe to take the shortcut when it is not. This could lead to data corruption. Process 1 and process2 each have a wp pte of the same anon page (ie. one forked the other). The page's mapcount is 2. Then they both attempt to write to it around the same time... proc1 proc2 thr1 proc2 thr2 CPU0 CPU1 CPU3 do_wp_page() do_wp_page() trylock_page() can_share_swap_page() load page mapcount (==2) reuse = 0 pte unlock copy page to new_page pte lock page_remove_rmap(page); trylock_page() can_share_swap_page() load page mapcount (==1) reuse = 1 ptep_set_access_flags (allow W) write private key into page read from page ptep_clear_flush() set_pte_at(pte of new_page) Fix this by moving the page_remove_rmap of the old page after the pte clear and flush. Potentially the entire branch could be moved down here, but in order to stay consistent, I won't (should probably move all the *_mm_counter stuff with one patch). Signed-off-by: Nick Piggin <npiggin@suse.de> Acked-by: Hugh Dickins <hugh@veritas.com> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-06-23Fix ZERO_PAGE breakage with vmwareLinus Torvalds
Commit 89f5b7da2a6bad2e84670422ab8192382a5aeb9f ("Reinstate ZERO_PAGE optimization in 'get_user_pages()' and fix XIP") broke vmware, as reported by Jeff Chua: "This broke vmware 6.0.4. Jun 22 14:53:03.845: vmx| NOT_IMPLEMENTED /build/mts/release/bora-93057/bora/vmx/main/vmmonPosix.c:774" and the reason seems to be that there's an old bug in how we handle do FOLL_ANON on VM_SHARED areas in get_user_pages(), but since it only triggered if the whole page table was missing, nobody had apparently hit it before. The recent changes to 'follow_page()' made the FOLL_ANON logic trigger not just for whole missing page tables, but for individual pages as well, and exposed this problem. This fixes it by making the test for when FOLL_ANON is used more careful, and also makes the code easier to read and understand by moving the logic to a separate inline function. Reported-and-tested-by: Jeff Chua <jeff.chua.linux@gmail.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-06-23removed unused var real_tty on n_tty_ioctl()Gustavo Fernando Padovan
I noted that the 'struct tty_struct *real_tty' is not used in this function, so I removed the code about 'real_tty'. Signed-off-by: Gustavo Fernando Padovan <gustavo@las.ic.unicamp.br> Acked-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-06-23tty_driver: Update required method documentationAlan Cox
Some of the requirement rules are now more relaxed. Also correct a contradiction in the previous update Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-06-23IB/mthca: Clear ICM pages before handing to FWEli Cohen
Current memfree FW has a bug which in some cases, assumes that ICM pages passed to it are cleared. This patch uses __GFP_ZERO to allocate all ICM pages passed to the FW. Once firmware with a fix is released, we can make the workaround conditional on firmware version. This fixes the bug reported by Arthur Kepner <akepner@sgi.com> here: http://lists.openfabrics.org/pipermail/general/2008-May/050026.html Cc: <stable@kernel.org> Signed-off-by: Eli Cohen <eli@mellanox.co.il> [ Rewritten to be a one-liner using __GFP_ZERO instead of vmap()ing ICM memory and memset()ing it to 0. - Roland ] Signed-off-by: Roland Dreier <rolandd@cisco.com>
2008-06-23futexes: fix fault handling in futex_lock_piThomas Gleixner
This patch addresses a very sporadic pi-futex related failure in highly threaded java apps on large SMP systems. David Holmes reported that the pi_state consistency check in lookup_pi_state triggered with his test application. This means that the kernel internal pi_state and the user space futex variable are out of sync. First we assumed that this is a user space data corruption, but deeper investigation revieled that the problem happend because the pi-futex code is not handling a fault in the futex_lock_pi path when the user space variable needs to be fixed up. The fault happens when a fork mapped the anon memory which contains the futex readonly for COW or the page got swapped out exactly between the unlock of the futex and the return of either the new futex owner or the task which was the expected owner but failed to acquire the kernel internal rtmutex. The current futex_lock_pi() code drops out with an inconsistent in case it faults and returns -EFAULT to user space. User space has no way to fixup that state. When we wrote this code we thought that we could not drop the hash bucket lock at this point to handle the fault. After analysing the code again it turned out to be wrong because there are only two tasks involved which might modify the pi_state and the user space variable: - the task which acquired the rtmutex - the pending owner of the pi_state which did not get the rtmutex Both tasks drop into the fixup_pi_state() function before returning to user space. The first task which acquired the hash bucket lock faults in the fixup of the user space variable, drops the spinlock and calls futex_handle_fault() to fault in the page. Now the second task could acquire the hash bucket lock and tries to fixup the user space variable as well. It either faults as well or it succeeds because the first task already faulted the page in. One caveat is to avoid a double fixup. After returning from the fault handling we reacquire the hash bucket lock and check whether the pi_state owner has been modified already. Reported-by: David Holmes <david.holmes@sun.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: David Holmes <david.holmes@sun.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: <stable@kernel.org> Signed-off-by: Ingo Molnar <mingo@elte.hu> kernel/futex.c | 93 ++++++++++++++++++++++++++++++++++++++++++++------------- 1 file changed, 73 insertions(+), 20 deletions(-)
2008-06-23ALSA: sb - Fix wrong assertionsTakashi Iwai
snd_assert() in save_mixer() and restore_mixer() in sb_mixer.c is just wrong. The debug code wasn't tested at all, obviously... Signed-off-by: Takashi Iwai <tiwai@suse.de>
2008-06-23ALSA: aw2 - Fix Oops at initializationTakashi Iwai
The irq handler may be called before the proper initialization of hardware. Call snd_aw2_saa7146_setup() before the irq handler registration. Signed-off-by: Takashi Iwai <tiwai@suse.de>
2008-06-23Merge branch 'linus' into sched/urgentIngo Molnar
2008-06-22[ARM] mv78xx0: add defconfigLennert Buytenhek
Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
2008-06-22[ARM] add Marvell 78xx0 ARM SoC supportStanislav Samsonov
The Marvell Discovery Duo (MV78xx0) is a family of ARM SoCs featuring (depending on the model) one or two Feroceon CPU cores with 512K of L2 cache and VFP coprocessors running at (depending on the model) between 800 MHz and 1.2 GHz, and features a DDR2 controller, two PCIe interfaces that can each run either in x4 or quad x1 mode, three USB 2.0 interfaces, two 3Gb/s SATA II interfaces, a SPI interface, two TWSI interfaces, a crypto accelerator, IDMA/XOR engines, a SPI interface, four UARTs, and depending on the model, two or four gigabit ethernet interfaces. This patch adds basic support for the platform, and allows booting on the MV78x00 development board, with functional UARTs, SATA, PCIe, GigE and USB ports. Signed-off-by: Stanislav Samsonov <samsonov@marvell.com> Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
2008-06-22[ARM] Orion: PCIe x4/x1 detection supportLennert Buytenhek
The Discovery Duo (MV78xx0) has two x4 PCIe ports which can either be used in x4 mode or in quad x1 mode. This patch adds an accessor function to the generic plat-orion PCIe handling code to detect in which of the two modes we're running (which is determined by strap pins and/or configured by the bootloader). Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
2008-06-22[ARM] Feroceon: 88fr571-vd supportLennert Buytenhek
Add support for the Feroceon 88fr571-vd CPU core as found in e.g. the Marvell Discovery Duo family of ARM SoCs. Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
2008-06-22[ARM] Kirkwood: add defconfigSaeed Bishara
Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
2008-06-22[ARM] add Marvell Kirkwood (88F6000) SoC supportSaeed Bishara
The Marvell Kirkwood (88F6000) is a family of ARM SoCs based on a Shiva CPU core, and features a DDR2 controller, a x1 PCIe interface, a USB 2.0 interface, a SPI controller, a crypto accelerator, a TS interface, and IDMA/XOR engines, and depending on the model, also features one or two Gigabit Ethernet interfaces, two SATA II interfaces, one or two TWSI interfaces, one or two UARTs, a TDM/SLIC interface, a NAND controller, an I2S/SPDIF interface, and an SDIO interface. This patch adds supports for the Marvell DB-88F6281-BP Development Board and the RD-88F6192-NAS and the RD-88F6281 Reference Designs, enabling support for the PCIe interface, the USB interface, the ethernet interfaces, the SATA interfaces, the TWSI interfaces, the UARTs, and the NAND controller. Signed-off-by: Saeed Bishara <saeed@marvell.com> Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
2008-06-22[ARM] Feroceon: 88fr131 supportLennert Buytenhek
Add support for the Shiva 88fr131 CPU core as found in e.g. the Marvell Kirkwood family of ARM SoCs. Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
2008-06-22[ARM] Feroceon: L2 cache supportLennert Buytenhek
This patch adds support for the unified Feroceon L2 cache controller as found in e.g. the Marvell Kirkwood and Marvell Discovery Duo families of ARM SoCs. Note that: - Page table walks are outer uncacheable on Kirkwood and Discovery Duo, since the ARMv5 spec provides no way to indicate outer cacheability of page table walks (specifying it in TTBR[4:3] is an ARMv6+ feature). This requires adding L2 cache clean instructions to proc-feroceon.S (dcache_clean_area(), set_pte()) as well as to tlbflush.h ({flush,clean}_pmd_entry()). The latter case is handled by defining a new TLB type (TLB_FEROCEON) which is almost identical to the v4wbi one but provides a TLB_L2CLEAN_FR flag. - The Feroceon L2 cache controller supports L2 range (i.e. 'clean L2 range by MVA' and 'invalidate L2 range by MVA') operations, and this patch uses those range operations for all Linux outer cache operations, as they are faster than the regular per-line operations. L2 range operations are not interruptible on this hardware, which avoids potential livelock issues, but can be bad for interrupt latency, so there is a compile-time tunable (MAX_RANGE_SIZE) which allows you to select the maximum range size to operate on at once. (Valid range is between one cache line and one 4KiB page, and must be a multiple of the line size.) Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
2008-06-22[ARM] Feroceon: L1 cache range operation supportStanislav Samsonov
This patch adds support for the L1 D cache range operations that are supported by the Marvell Discovery Duo and Marvell Kirkwood ARM SoCs. Signed-off-by: Stanislav Samsonov <samsonov@marvell.com> Acked-by: Saeed Bishara <saeed@marvell.com> Reviewed-by: Nicolas Pitre <nico@marvell.com> Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
2008-06-22[ARM] Loki: add defconfigLennert Buytenhek
Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
2008-06-22[ARM] add Marvell Loki (88RC8480) SoC supportLennert Buytenhek
The Marvell Loki (88RC8480) is an ARM SoC based on a Feroceon CPU core running at between 400 MHz and 1.0 GHz, and features a 64 bit DDR controller, 512K of internal SRAM, two x4 PCI-Express ports, two Gigabit Ethernet ports, two 4x SAS/SATA controllers, two UARTs, two TWSI controllers, and IDMA/XOR engines. This patch adds support for the Marvell LB88RC8480 Development Board, enabling the use of the PCIe interfaces, the ethernet interfaces, the TWSI interfaces and the UARTs. Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
2008-06-22[ARM] Orion: add a separate BRIDGE_INT_TIMER1_CLR defineKe Wei
Some Feroceon-based SoCs have an MBUS bridge interrupt controller that requires writing a one instead of a zero to clear edge interrupt sources such as timer expiry. This patch adds a new BRIDGE_INT_TIMER1_CLR define, which platform code can set to either ~BRIDGE_INT_TIMER1 (write-zero-to-clear) or BRIDGE_INT_TIMER1 (write-one-to-clear) depending on the platform. Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
2008-06-22[ARM] Feroceon: allow more old Feroceon IDsKe Wei
There are a couple more Feroceon-based SoCs out in the field that use different Variant and Architecture fields in their Main ID registers -- this patch tweaks the processor match/mask in proc-feroceon.S to catch those SoCs as well. Signed-off-by: Ke Wei <kewei@marvell.com> Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
2008-06-22[ARM] Feroceon: catch other Feroceon CPU IDs in head.SNicolas Pitre
Tweak the Feroceon match/mask in arch/arm/boot/compressed/head.S to match a couple of newer Feroceon cores (such as the 88fr571vd with CPU ID 0x56155710, and the 88fr131 with CPU ID 0x56251310) as well. Signed-off-by: Nicolas Pitre <nico@marvell.com> Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
2008-06-22[ARM] Feroceon: speed up flushing of the entire cacheNicolas Pitre
Flushing the L1 D cache with a test/clean/invalidate loop is very easy in software, but it is not the quickest way of doing it, as there is a lot of overhead involved in re-scanning the cache from the beginning every time we hit a dirty line. This patch makes proc-feroceon.S use "clean+invalidate by set/way" loops according to possible cache configuration of Feroceon CPUs (either direct-mapped or 4-way set associative). Signed-off-by: Nicolas Pitre <nico@marvell.com> Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
2008-06-22[ARM] Orion: nuke orion5x_{read,write}Lennert Buytenhek
Nuke the Orion-specific orion5x_{read,write} wrappers. Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
2008-06-22[ARM] Orion: use linux/serial_reg.h for Orion uncompress.hLennert Buytenhek
Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
2008-06-22[ARM] Orion: add Maxtor Shared Storage II supportSylver Bruneau
This patch adds support for the Maxtor Shared Storage II hardware. Signed-off-by: Sylver Bruneau <sylver.bruneau@googlemail.com> Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
2008-06-22[ARM] Orion: add Technologic Systems TS-78xx supportAlexander Clouter
Signed-off-by: Alexander Clouter <alex@digriz.org.uk> Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
2008-06-22[ARM] Orion: remove code duplication in TS209 and TS409 setup filesSylver Bruneau
Signed-off-by: Sylver Bruneau <sylver.bruneau@googlemail.com> Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
2008-06-22[ARM] Orion: add HP Media Vault mv2120 supportMartin Michlmayr
Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
2008-06-22[ARM] Orion: add Linksys WRT350N v2 supportLennert Buytenhek
Signed-off-by: Lennert Buytenhek <buytenh@marvell.com> Tested-by: Dirk Teurlings <dirk@upexia.nl> Tested-by: Peter van Valderen <p.v.valderen@gmail.com>
2008-06-22[ARM] Orion: add 88F5181L (Orion-VoIP) supportLennert Buytenhek
Signed-off-by: Lennert Buytenhek <buytenh@marvell.com> Acked-by: Russell King <linux@arm.linux.org.uk>
2008-06-22[ARM] Orion: add QNAP TS-409 supportSylver Bruneau
Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
2008-06-22[ARM] Orion: implement power-off method for Kurobox ProSylver Bruneau
This patch implements the communication with the microcontroller on the Kurobox Pro and Linkstation Pro/Live boards. This is allowing to send the commands needed to power-off the board correctly. Signed-off-by: Sylver Bruneau <sylver.bruneau@googlemail.com> Acked-by: Russell King <linux@arm.linux.org.uk> Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
2008-06-22[ARM] Orion: avoid setting ->force_phy_addrLennert Buytenhek
The mv643xx_eth platform data field ->force_phy_addr only needs to be set if the passed-in ->phy_addr field is zero (to distinguish the case of not having specified a phy address (force_phy_addr = 0) from the case where a phy address of zero needs to be used (force_phy_addr = 1.)) Also, the ->force_phy_addr field will hopefully disappear in a future mv643xx_eth reorganisation. Therefore, this patch deletes the ->force_phy_addr field initialiser from all Orion board code. Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
2008-06-22[ARM] Orion: remove error printks in ->map_irq() implementationsLennert Buytenhek
If all PCI devices are working as expected, the error printks in the various implementations of ->map_irq() doesn't really provide any useful info. And if something is not working as expected, turning on pci=debug gives you more useful information than the printk calls in ->map_irq(), since the former also tells you which devices _did_ get IRQs successfully assigned. Therefore, delete these printks entirely. Spotted by Russell King. Signed-off-by: Lennert Buytenhek <buytenh@marvell.com> Acked-by: Russell King <linux@arm.linux.org.uk>
2008-06-22[ARM] Orion: rework MPP handlingLennert Buytenhek
Instead of having board code poke directly into the MPP configuration registers, and separately calling orion5x_gpio_set_valid_pins() to indicate which MPP pins can be used as GPIO pins, introduce a helper function for configuring the roles of each of the MPP pins, and have that helper function handle gpio validity internally. Signed-off-by: Lennert Buytenhek <buytenh@marvell.com> Acked-by: Sylver Bruneau <sylver.bruneau@googlemail.com> Acked-by: Russell King <linux@arm.linux.org.uk>
2008-06-22[ARM] Orion: move setting up PCIe WA window into PCIe setup pathLennert Buytenhek
It makes no sense to do PCIe WA window setup in the individual board support files while the decision whether or not to use the PCIe WA access method is made in a different place, in the PCIe support code. This patch moves the configuration of a PCIe WA window from the individual Orion board support files to the central Orion PCIe support code. Signed-off-by: Lennert Buytenhek <buytenh@marvell.com> Acked-by: Russell King <linux@arm.linux.org.uk>
2008-06-22[ARM] Orion: move EHCI/I2C/UART peripheral init into board codeLennert Buytenhek
This patch moves initialisation of EHCI/I2C/UART platform devices from the common orion5x_init() into the board support code. The rationale behind this is that only the board support code knows whether certain peripherals have been brought out on the board, and not initialising peripherals that haven't been brought out is desirable for example: - to reduce user confusion (e.g. seeing both 'eth0' and 'eth1' appear while there is only one ethernet port on the board); and - to allow for future power savings (peripherals that have not been brought out can be clock gated off entirely). Signed-off-by: Lennert Buytenhek <buytenh@marvell.com> Acked-by: Russell King <linux@arm.linux.org.uk>
2008-06-22[ARM] Orion: delete unused IO_SPACE_REMAP defineLennert Buytenhek
This define isn't used anywhere in the kernel tree -- nuke it. Signed-off-by: Lennert Buytenhek <buytenh@marvell.com> Acked-by: Russell King <linux@arm.linux.org.uk>
2008-06-22[ARM] Orion: top-level IRQs are level-triggeredLennert Buytenhek
Make it clear that Orion top-level IRQs are level-triggered. This means that we don't need an ->ack() handler, or at least, we don't need the ->ack() handler (or the acking part of the ->mask_ack() handler) to actually do anything. Given that, we might as well point our ->mask_ack() handler at the ->mask() handler instead of providing a dummy ->ack() handler, since providing a ->mask_ack() handler on level IRQ sources will prevent ->ack() from ever being called. Signed-off-by: Lennert Buytenhek <buytenh@marvell.com> Acked-by: Russell King <linux@arm.linux.org.uk>
2008-06-22[ARM] Feroceon: annotate 88fr531-vd CPU entriesLennert Buytenhek
Annotate the entries for the 88fr531-vd CPU core in arch/arm/boot/compressed/head.S and arch/arm/mm/proc-feroceon.S with the full name of the core. Signed-off-by: Lennert Buytenhek <buytenh@marvell.com> Acked-by: Russell King <linux@arm.linux.org.uk>
2008-06-22[ARM] Orion: DRAM mapping granularity is 64KiB, not 16MiBLennert Buytenhek
The DRAM base address and size fields in the CPU's MBUS bridge have 64KiB granularity, instead of the currently used 16MiB. Since all of the currently supported MBUS peripherals support 64KiB granularity as well, this patch changes the Orion address map code to stop rounding base addresses down and sizes up to multiples of 16MiB. Found by Ke Wei <kewei@marvell.com>. Signed-off-by: Lennert Buytenhek <buytenh@marvell.com> Acked-by: Russell King <linux@arm.linux.org.uk>
2008-06-22[ARM] Orion: make window setup a little more safeLennert Buytenhek
Currently, Orion window setup uses hardcoded window indexes for each of the boot/cs0/cs1/cs2/PCIe WA windows. The static window allocation used can clash if board support code will ever attempt to configure both a dev2 and a PCIe WA window, as both of those use CPU mbus window #7 at present. This patch keeps track of the last used window, and opens subsequently requested windows sequentially, starting from 4. (Windows 0-3 are used as MEM/IO windows for the PCI/PCIe buses.) Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
2008-06-22[ARM] Orion: fix various whitespace and coding style issuesLennert Buytenhek
More cosmetic cleanup: - Replace 8-space indents by proper tab indents. - In structure initialisers, use a trailing comma for every member. - Collapse "},\n{" in structure initialiers to "}, {". Signed-off-by: Lennert Buytenhek <buytenh@marvell.com> Acked-by: Russell King <linux@arm.linux.org.uk>
2008-06-22[ARM] cache align memset and memzeroNicolas Pitre
This is a natural extension following the previous patch. Non Feroceon based targets are unchanged. Signed-off-by: Nicolas Pitre <nico@marvell.com> Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
2008-06-22[ARM] cache align destination pointer when copying memory for some processorsNicolas Pitre
The implementation for memory copy functions on ARM had a (disabled) provision for aligning the source pointer before loading registers with data. Turns out that aligning the _destination_ pointer is much more useful, as the read side is already sufficiently helped with the use of preload. So this changes the definition of the CALGN() macro to target the destination pointer instead, and turns it on for Feroceon processors where the gain is very noticeable. Signed-off-by: Nicolas Pitre <nico@marvell.com> Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
2008-06-22[ARM] fix cache alignment code in memset.SNicolas Pitre
This code is currently disabled, which explains why no one was affected. Signed-off-by: Nicolas Pitre <nico@marvell.com> Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
2008-06-22[ARM] latencytop supportNicolas Pitre
Available for !SMP only at the moment. From Russell: |Basically, if a thread is running on a CPU, thread_saved_fp() is invalid. |So, the question is: what guarantees do we have here that 'tsk' is not |running on another CPU? Signed-off-by: Nicolas Pitre <nico@marvell.com> Tested-by: Lennert Buytenhek <buytenh@marvell.com> Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>