lwn.git/drivers/misc, branch v4.1.21

cxl: Don't remove AFUs/vPHBs in cxl_reset

2015-09-29T17:26:26+00:00

commit 4e1efb403c1c016ae831bd9988a7d2e5e0af41a0 upstream. If the driver doesn't participate in EEH, the AFUs will be removed by cxl_remove, which will be invoked by EEH. If the driver does particpate in EEH, the vPHB needs to stick around so that the it can particpate. In both cases, we shouldn't remove the AFU/vPHB. Reviewed-by: Cyril Bur Signed-off-by: Daniel Axtens Signed-off-by: Michael Ellerman Reported-by: Guenter Roeck Signed-off-by: Sudip Mukherjee Signed-off-by: Greg Kroah-Hartman

cxl: Fix unbalanced pci_dev_get in cxl_probe

2015-09-29T17:25:58+00:00

commit 2925c2fdf1e0eb642482f5b30577e9435aaa8edb upstream. Currently the first thing we do in cxl_probe is to grab a reference on the pci device. Later on, we call device_register on our adapter. In our remove path, we call device_unregister, but we never call pci_dev_put. We therefore leak the device every time we do a reflash. device_register/unregister is sufficient to hold the reference. Therefore, drop the call to pci_dev_get. Here's why this is safe. The proposed cxl_probe(pdev) calls cxl_adapter_init: a) init calls cxl_adapter_alloc, which creates a struct cxl, conventionally called adapter. This struct contains a device entry, adapter->dev. b) init calls cxl_configure_adapter, where we set adapter->dev.parent = &dev->dev (here dev is the pci dev) So at this point, the cxl adapter's device's parent is the PCI device that I want to be refcounted properly. c) init calls cxl_register_adapter *) cxl_register_adapter calls device_register(&adapter->dev) So now we're in device_register, where dev is the adapter device, and we want to know if the PCI device is safe after we return. device_register(&adapter->dev) calls device_initialize() and then device_add(). device_add() does a get_device(). device_add() also explicitly grabs the device's parent, and calls get_device() on it: parent = get_device(dev->parent); So therefore, device_register() takes a lock on the parent PCI dev, which is what pci_dev_get() was guarding. pci_dev_get() can therefore be safely removed. Fixes: f204e0b8cedd ("cxl: Driver code for powernv PCIe based cards for userspace access") Signed-off-by: Daniel Axtens Acked-by: Ian Munsie Signed-off-by: Michael Ellerman Signed-off-by: Greg Kroah-Hartman

cxl: Remove racy attempt to force EEH invocation in reset

2015-09-29T17:25:57+00:00

commit 9d8e27673c45927fee9e7d8992ffb325a6b0b0e4 upstream. cxl_reset currently PERSTs the slot, and then repeatedly tries to read MMIO space in order to kick off EEH. There are 2 problems with this: it's unnecessary, and it's racy. It's unnecessary because the PERST will bring down the PHB link. That will be picked up by the CAPP, which will send out an HMI. Skiboot, noticing an HMI from the CAPP, will send an OPAL notification to the kernel, which will trigger EEH recovery. It's also racy: the EEH recovery triggered by the CAPP will eventually cause the MMIO space to have its mapping invalidated and the pointer NULLed out. This races with our attempt to read the MMIO space. This is causing OOPSes in testing. Simply drop all the attempts to force EEH detection, and trust that Skiboot will send the notification and that we'll act on it. The Skiboot code to send the EEH notification has been in Skiboot for as long as CAPP recovery has been supported, so we don't need to worry about breaking obscure setups with ancient firmware. Cc: Ryan Grimm Fixes: 62fa19d4b4fd ("cxl: Add ability to reset the card") Signed-off-by: Daniel Axtens Acked-by: Ian Munsie Signed-off-by: Michael Ellerman Signed-off-by: Greg Kroah-Hartman

mei: prevent unloading mei hw modules while the device is opened.

2015-08-10T19:21:57+00:00

commit 154322f47376fed6ab1e4b350aa45fffa15a61aa upstream. chrdev_open() increases reference counter on cdev->owner. Instead of assigning the owner to mei subsystem, the owner has to be set to the underlaying HW module (mei_me or mei_txe), so once the device is opened the HW module cannot be unloaded. Signed-off-by: Tomas Winkler Signed-off-by: Alexander Usyskin Signed-off-by: Greg Kroah-Hartman

cxl: Check if afu is not null in cxl_slbia

2015-08-10T19:21:50+00:00

commit 2c069a118fe1d80c47dca84e1561045fc7f3cc9e upstream. The pointer to an AFU in the adapter's list of AFUs can be null if we're in the process of removing AFUs. The afu_list_lock doesn't guard against this. Say we have 2 slices, and we're in the process of removing cxl. - We remove the AFUs in order (see cxl_remove). In cxl_remove_afu for AFU 0, we take the lock, set adapter->afu[0] = NULL, and release the lock. - Then we get an slbia. In cxl_slbia we take the lock, and set afu = adapter->afu[0], which is NULL. - Therefore our attempt to check afu->enabled will blow up. Therefore, check if afu is a null pointer before dereferencing it. Signed-off-by: Daniel Axtens Acked-by: Michael Neuling Acked-by: Ian Munsie Signed-off-by: Michael Ellerman Signed-off-by: Greg Kroah-Hartman

cxl: Fix off by one error allowing subsequent mmap page to be accessed

2015-08-10T19:21:50+00:00

commit 10a5894f2dedd8a26b3132497445b314c0d952c4 upstream. It was discovered that if a process mmaped their problem state area they were able to access one page more than expected, potentially allowing them to access the problem state area of an unrelated process. This was due to a simple off by one error in the mmap fault handler introduced in 0712dc7e73e59d79bcead5d5520acf4e9e917e87 ("cxl: Fix issues when unmapping contexts"), which is fixed in this patch. Fixes: 0712dc7e73e5 ("cxl: Fix issues when unmapping contexts") Signed-off-by: Ian Munsie Signed-off-by: Michael Ellerman Signed-off-by: Greg Kroah-Hartman

mei: txe: reduce suspend/resume time

2015-07-21T17:10:03+00:00

commit fe292283c23329218e384bffc6cb4bfa3fd92277 upstream. HW has to be in known state before the initialisation sequence is started. The polling step for settling aliveness was set to 200ms while in practise this can be done in up to 30msecs. Signed-off-by: Tomas Winkler Signed-off-by: Barak Yoresh Signed-off-by: Greg Kroah-Hartman

mei: me: wait for power gating exit confirmation

2015-07-21T17:10:03+00:00

commit 3dc196eae1db548f05e53e5875ff87b8ff79f249 upstream. Fix the hbm power gating state machine so it will wait till it receives confirmation interrupt for the PG_ISOLATION_EXIT message. In process of the suspend flow the devices first have to exit from the power gating state (runtime pm resume). If we do not handle the confirmation interrupt after sending PG_ISOLATION_EXIT message, we may receive it already after the suspend flow has changed the device state and interrupt will be interpreted as a spurious event, consequently link reset will be invoked which will prevent the device from completing the suspend flow kernel: [6603] mei_reset:136: mei_me 0000:00:16.0: powering down: end of reset kernel: [476] mei_me_irq_thread_handler:643: mei_me 0000:00:16.0: function called after ISR to handle the interrupt processing. kernel: mei_me 0000:00:16.0: FW not ready: resetting Cc: Gabriele Mazzotta Link: https://bugzilla.kernel.org/show_bug.cgi?id=86241 Link: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=770397 Tested-by: Gabriele Mazzotta Signed-off-by: Alexander Usyskin Signed-off-by: Tomas Winkler Signed-off-by: Greg Kroah-Hartman

Merge tag 'char-misc-4.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc

2015-04-21T16:42:58+00:00

Pull char/misc driver updates from Greg KH: "Here's the big char/misc driver patchset for 4.1-rc1. Lots of different driver subsystem updates here, nothing major, full details are in the shortlog. All of this has been in linux-next for a while" * tag 'char-misc-4.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (133 commits) mei: trace: remove unused TRACE_SYSTEM_STRING DTS: ARM: OMAP3-N900: Add lis3lv02d support Documentation: DT: lis302: update wakeup binding lis3lv02d: DT: add wakeup unit 2 and wakeup threshold lis3lv02d: DT: use s32 to support negative values Drivers: hv: hv_balloon: correctly handle num_pages>INT_MAX case Drivers: hv: hv_balloon: correctly handle val.freeram

Merge branch 'for-linus-1' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

2015-04-14T22:31:03+00:00

Pull vfs update from Al Viro: "Part one: - struct filename-related cleanups - saner iov_iter_init() replacements (and switching the syscalls to use of those) - ntfs switch to ->write_iter() (Anton) - aio cleanups and splitting iocb into common and async parts (Christoph) - assorted fixes (me, bfields, Andrew Elble) There's a lot more, including the completion of switchover to ->{read,write}_iter(), d_inode/d_backing_inode annotations, f_flags race fixes, etc, but that goes after #for-davem merge. David has pulled it, and once it's in I'll send the next vfs pull request" * 'for-linus-1' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (35 commits) sg_start_req(): use import_iovec() sg_start_req(): make sure that there's not too many elements in iovec blk_rq_map_user(): use import_single_range() sg_io(): use import_iovec() process_vm_access: switch to {compat_,}import_iovec() switch keyctl_instantiate_key_common() to iov_iter switch {compat_,}do_readv_writev() to {compat_,}import_iovec() aio_setup_vectored_rw(): switch to {compat_,}import_iovec() vmsplice_to_user(): switch to import_iovec() kill aio_setup_single_vector() aio: simplify arguments of aio_setup_..._rw() aio: lift iov_iter_init() into aio_setup_..._rw() lift iov_iter into {compat_,}do_readv_writev() NFS: fix BUG() crash in notify_change() with patch to chown_common() dcache: return -ESTALE not -EBUSY on distributed fs race NTFS: Version 2.1.32 - Update file write from aio_write to write_iter. VFS: Add iov_iter_fault_in_multipages_readable() drop bogus check in file_open_root() switch security_inode_getattr() to struct path * constify tomoyo_realpath_from_path() ...