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2017-09-29cxl: Fix memory page not handledChristophe Lombard1-2/+11
The in-kernel 'library' API can be called by drivers to help interaction with an IBM XSL on a POWER9 system. The cxllib_handle_fault() API is used to handle memory fault. All memory pages of the specified buffer have to be handled but under certain conditions,the last page may not be touched, and the address the adapter is trying to access is never sent to the kernel for resolution. This patch reworks start address of the loop with an address aligned on the page size. In this context, the last page is not missed. Signed-off-by: Christophe Lombard <clombard@linux.vnet.ibm.com> Acked-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com> Acked-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Fixes: 3ced8d730063 ("cxl: Export library to support IBM XSL"); Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-09-14mm: treewide: remove GFP_TEMPORARY allocation flagMichal Hocko1-1/+1
GFP_TEMPORARY was introduced by commit e12ba74d8ff3 ("Group short-lived and reclaimable kernel allocations") along with __GFP_RECLAIMABLE. It's primary motivation was to allow users to tell that an allocation is short lived and so the allocator can try to place such allocations close together and prevent long term fragmentation. As much as this sounds like a reasonable semantic it becomes much less clear when to use the highlevel GFP_TEMPORARY allocation flag. How long is temporary? Can the context holding that memory sleep? Can it take locks? It seems there is no good answer for those questions. The current implementation of GFP_TEMPORARY is basically GFP_KERNEL | __GFP_RECLAIMABLE which in itself is tricky because basically none of the existing caller provide a way to reclaim the allocated memory. So this is rather misleading and hard to evaluate for any benefits. I have checked some random users and none of them has added the flag with a specific justification. I suspect most of them just copied from other existing users and others just thought it might be a good idea to use without any measuring. This suggests that GFP_TEMPORARY just motivates for cargo cult usage without any reasoning. I believe that our gfp flags are quite complex already and especially those with highlevel semantic should be clearly defined to prevent from confusion and abuse. Therefore I propose dropping GFP_TEMPORARY and replace all existing users to simply use GFP_KERNEL. Please note that SLAB users with shrinkers will still get __GFP_RECLAIMABLE heuristic and so they will be placed properly for memory fragmentation prevention. I can see reasons we might want some gfp flag to reflect shorterm allocations but I propose starting from a clear semantic definition and only then add users with proper justification. This was been brought up before LSF this year by Matthew [1] and it turned out that GFP_TEMPORARY really doesn't have a clear semantic. It seems to be a heuristic without any measured advantage for most (if not all) its current users. The follow up discussion has revealed that opinions on what might be temporary allocation differ a lot between developers. So rather than trying to tweak existing users into a semantic which they haven't expected I propose to simply remove the flag and start from scratch if we really need a semantic for short term allocations. [1] http://lkml.kernel.org/r/20170118054945.GD18349@bombadil.infradead.org [akpm@linux-foundation.org: fix typo] [akpm@linux-foundation.org: coding-style fixes] [sfr@canb.auug.org.au: drm/i915: fix up] Link: http://lkml.kernel.org/r/20170816144703.378d4f4d@canb.auug.org.au Link: http://lkml.kernel.org/r/20170728091904.14627-1-mhocko@kernel.org Signed-off-by: Michal Hocko <mhocko@suse.com> Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Acked-by: Mel Gorman <mgorman@suse.de> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Matthew Wilcox <willy@infradead.org> Cc: Neil Brown <neilb@suse.de> Cc: "Theodore Ts'o" <tytso@mit.edu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-08-31cxl: Fix driver use countFrederic Barrat2-1/+11
cxl keeps a driver use count, which is used with the hash memory model on p8 to know when to upgrade local TLBIs to global and to trigger callbacks to manage the MMU for PSL8. If a process opens a context and closes without attaching or fails the attachment, the driver use count is never decremented. As a consequence, TLB invalidations remain global, even if there are no active cxl contexts. We should increment the driver use count when the process is attaching to the cxl adapter, and not on open. It's not needed before the adapter starts using the context and the use count is decremented on the detach path, so it makes more sense. It affects only the user api. The kernel api is already doing The Right Thing. Signed-off-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com> Cc: stable@vger.kernel.org # v4.2+ Fixes: 7bb5d91a4dda ("cxl: Rework context lifetimes") Acked-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-31powerpc/mm/cxl: Add barrier when setting mm cpumaskAneesh Kumar K.V1-2/+12
We need to add memory barrier so that the page table walk doesn't happen before the cpumask is set and made visible to the other cpus. We need to use a sync here instead of lwsync because lwsync is not sufficient for store/load ordering. We also need to add an if (mm) check so that we do the right thing when called with a kernel context. For kernel context, we have mm = NULL. W.r.t kernel address we can skip setting the mm cpumask. Fixes: 0f4bc0932e ("powerpc/mm/cxl: Add the fault handling cpu to mm cpumask") Cc: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Reported-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Acked-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-17powerpc/mm/cxl: Add the fault handling cpu to mm cpumaskAneesh Kumar K.V1-0/+6
We use mm cpumask for serializing against lockless page table walk. Anybody who is doing a lockless page table walk is expected to disable irq and only cpus in mm cpumask is expected do the lockless walk. This ensure that a THP split can send IPI to only cpus in the mm cpumask, to make sure there are no parallel lockless page table walk. Add the CAPI fault handling cpu to the mm cpumask so that we can do the lockless page table walk while inserting hash page table entries. Reviewed-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-07-03cxl: Export library to support IBM XSLChristophe Lombard7-30/+315
This patch exports a in-kernel 'library' API which can be called by other drivers to help interacting with an IBM XSL on a POWER9 system. The XSL (Translation Service Layer) is a stripped down version of the PSL (Power Service Layer) used in some cards such as the Mellanox CX5. Like the PSL, it implements the CAIA architecture, but has a number of differences, mostly in it's implementation dependent registers. The XSL also uses a special DMA cxl mode, which uses a slightly different init sequence for the CAPP and PHB. Signed-off-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Signed-off-by: Christophe Lombard <clombard@linux.vnet.ibm.com> Acked-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-07-03Merge branch 'fixes' into nextMichael Ellerman7-55/+70
Merge our fixes branch, a few of them are tripping people up while working on top of next, and we also have a dependency between the CXL fixes and new CXL code we want to merge into next.
2017-06-23cxl: Fixes for Coherent Accelerator Interface Architecture 2.0Christophe Lombard6-47/+57
A previous set of patches "cxl: Add support for Coherent Accelerator Interface Architecture 2.0" has introduced a new support for the CAPI cards. These patches have been tested on Simulation environment and quite a bit of them have been tested on real hardware. This patch brings new fixes after a series of tests carried out on new equipment: - Add POWER9 definition. - Re-enable any masked interrupts when the AFU is not activated after resetting the AFU. - Remove the api cxl_is_psl8/9 which is no longer useful. - Do not dump CAPI1 registers. - Rewrite cxl_is_page_fault() function. - Do not register slb callack on P9. Fixes: f24be42aab37 ("cxl: Add psl9 specific code") Signed-off-by: Christophe Lombard <clombard@linux.vnet.ibm.com> Acked-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-06-08cxl: Fix error path on bad ioctlFrederic Barrat1-5/+2
Fix error path if we can't copy user structure on CXL_IOCTL_START_WORK ioctl. We shouldn't unlock the context status mutex as it was not locked (yet). Fixes: 0712dc7e73e5 ("cxl: Fix issues when unmapping contexts") Cc: stable@vger.kernel.org # v3.19+ Signed-off-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com> Reviewed-by: Vaibhav Jain <vaibhav@linux.vnet.ibm.com> Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-06-06cxl: Unlock on error in probeDan Carpenter1-2/+6
We should unlock if get_cxl_adapter() fails. Fixes: 594ff7d067ca ("cxl: Support to flash a new image on the adapter from a guest") Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Acked-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-06-06cxl: Avoid double free_irq() for psl,slice interruptsVaibhav Jain1-3/+11
During an eeh call to cxl_remove can result in double free_irq of psl,slice interrupts. This can happen if perst_reloads_same_image == 1 and call to cxl_configure_adapter() fails during slot_reset callback. In such a case we see a kernel oops with following back-trace: Oops: Kernel access of bad area, sig: 11 [#1] Call Trace: free_irq+0x88/0xd0 (unreliable) cxl_unmap_irq+0x20/0x40 [cxl] cxl_native_release_psl_irq+0x78/0xd8 [cxl] pci_deconfigure_afu+0xac/0x110 [cxl] cxl_remove+0x104/0x210 [cxl] pci_device_remove+0x6c/0x110 device_release_driver_internal+0x204/0x2e0 pci_stop_bus_device+0xa0/0xd0 pci_stop_and_remove_bus_device+0x28/0x40 pci_hp_remove_devices+0xb0/0x150 pci_hp_remove_devices+0x68/0x150 eeh_handle_normal_event+0x140/0x580 eeh_handle_event+0x174/0x360 eeh_event_handler+0x1e8/0x1f0 This patch fixes the issue of double free_irq by checking that variables that hold the virqs (err_hwirq, serr_hwirq, psl_virq) are not '0' before un-mapping and resetting these variables to '0' when they are un-mapped. Cc: stable@vger.kernel.org Signed-off-by: Vaibhav Jain <vaibhav@linux.vnet.ibm.com> Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Acked-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-05-05Merge tag 'powerpc-4.12-1' of ↵Linus Torvalds13-308/+1104
git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc updates from Michael Ellerman: "Highlights include: - Larger virtual address space on 64-bit server CPUs. By default we use a 128TB virtual address space, but a process can request access to the full 512TB by passing a hint to mmap(). - Support for the new Power9 "XIVE" interrupt controller. - TLB flushing optimisations for the radix MMU on Power9. - Support for CAPI cards on Power9, using the "Coherent Accelerator Interface Architecture 2.0". - The ability to configure the mmap randomisation limits at build and runtime. - Several small fixes and cleanups to the kprobes code, as well as support for KPROBES_ON_FTRACE. - Major improvements to handling of system reset interrupts, correctly treating them as NMIs, giving them a dedicated stack and using a new hypervisor call to trigger them, all of which should aid debugging and robustness. - Many fixes and other minor enhancements. Thanks to: Alastair D'Silva, Alexey Kardashevskiy, Alistair Popple, Andrew Donnellan, Aneesh Kumar K.V, Anshuman Khandual, Anton Blanchard, Balbir Singh, Ben Hutchings, Benjamin Herrenschmidt, Bhupesh Sharma, Chris Packham, Christian Zigotzky, Christophe Leroy, Christophe Lombard, Daniel Axtens, David Gibson, Gautham R. Shenoy, Gavin Shan, Geert Uytterhoeven, Guilherme G. Piccoli, Hamish Martin, Hari Bathini, Kees Cook, Laurent Dufour, Madhavan Srinivasan, Mahesh J Salgaonkar, Mahesh Salgaonkar, Masami Hiramatsu, Matt Brown, Matthew R. Ochs, Michael Neuling, Naveen N. Rao, Nicholas Piggin, Oliver O'Halloran, Pan Xinhui, Paul Mackerras, Rashmica Gupta, Russell Currey, Sukadev Bhattiprolu, Thadeu Lima de Souza Cascardo, Tobin C. Harding, Tyrel Datwyler, Uma Krishnan, Vaibhav Jain, Vipin K Parashar, Yang Shi" * tag 'powerpc-4.12-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (214 commits) powerpc/64s: Power9 has no LPCR[VRMASD] field so don't set it powerpc/powernv: Fix TCE kill on NVLink2 powerpc/mm/radix: Drop support for CPUs without lockless tlbie powerpc/book3s/mce: Move add_taint() later in virtual mode powerpc/sysfs: Move #ifdef CONFIG_HOTPLUG_CPU out of the function body powerpc/smp: Document irq enable/disable after migrating IRQs powerpc/mpc52xx: Don't select user-visible RTAS_PROC powerpc/powernv: Document cxl dependency on special case in pnv_eeh_reset() powerpc/eeh: Clean up and document event handling functions powerpc/eeh: Avoid use after free in eeh_handle_special_event() cxl: Mask slice error interrupts after first occurrence cxl: Route eeh events to all drivers in cxl_pci_error_detected() cxl: Force context lock during EEH flow powerpc/64: Allow CONFIG_RELOCATABLE if COMPILE_TEST powerpc/xmon: Teach xmon oops about radix vectors powerpc/mm/hash: Fix off-by-one in comment about kernel contexts ids powerpc/pseries: Enable VFIO powerpc/powernv: Fix iommu table size calculation hook for small tables powerpc/powernv: Check kzalloc() return value in pnv_pci_table_alloc powerpc: Add arch/powerpc/tools directory ...
2017-05-03Merge branch 'for-linus' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial Pull trivial tree updates from Jiri Kosina. * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: tty: fix comment for __tty_alloc_driver() init/main: properly align the multi-line comment init/main: Fix double "the" in comment Fix dead URLs to ftp.kernel.org drivers: Clean up duplicated email address treewide: Fix typo in xml/driver-api/basics.xml tools/testing/selftests/powerpc: remove redundant CFLAGS in Makefile: "-Wall -O2 -Wall" -> "-O2 -Wall" selftests/timers: Spelling s/privledges/privileges/ HID: picoLCD: Spelling s/REPORT_WRTIE_MEMORY/REPORT_WRITE_MEMORY/ net: phy: dp83848: Fix Typo UBI: Fix typos Documentation: ftrace.txt: Correct nice value of 120 priority net: fec: Fix typo in error msg and comment treewide: Fix typos in printk
2017-05-02cxl: Mask slice error interrupts after first occurrenceAlastair D'Silva2-2/+35
In some situations, a faulty AFU slice may create an interrupt storm of slice errors, rendering the machine unusable. Since these interrupts are informational only, present the interrupt once, then mask it off to prevent it from being retriggered until the AFU is reset. Signed-off-by: Alastair D'Silva <alastair@d-silva.org> Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Reviewed-by: Vaibhav Jain <vaibhav@linux.vnet.ibm.com> Acked-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-05-02cxl: Route eeh events to all drivers in cxl_pci_error_detected()Vaibhav Jain1-6/+9
Fix a boundary condition where in some cases an eeh event that results in card reset isn't passed on to a driver attached to the virtual PCI device associated with a slice. This will happen in case when a slice attached device driver returns a value other than PCI_ERS_RESULT_NEED_RESET from the eeh error_detected() callback. This would result in an early return from cxl_pci_error_detected() and other drivers attached to other AFUs on the card wont be notified. The patch fixes this by making sure that all slice attached device-drivers are notified and the return values from error_detected() callback are aggregated in a scheme where request for 'disconnect' trumps all and 'none' trumps 'need_reset'. Fixes: 9e8df8a21963 ("cxl: EEH support") Cc: stable@vger.kernel.org # v4.3+ Signed-off-by: Vaibhav Jain <vaibhav@linux.vnet.ibm.com> Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Acked-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-05-02cxl: Force context lock during EEH flowVaibhav Jain1-2/+17
During an eeh event when the cxl card is fenced and card sysfs attr perst_reloads_same_image is set following warning message is seen in the kernel logs: Adapter context unlocked with 0 active contexts ------------[ cut here ]------------ WARNING: CPU: 12 PID: 627 at ../drivers/misc/cxl/main.c:325 cxl_adapter_context_unlock+0x60/0x80 [cxl] Even though this warning is harmless, it clutters the kernel log during an eeh event. This warning is triggered as the EEH callback cxl_pci_error_detected doesn't obtain a context-lock before forcibly detaching all active context and when context-lock is released during call to cxl_configure_adapter from cxl_pci_slot_reset, a warning in cxl_adapter_context_unlock is triggered. To fix this warning, we acquire the adapter context-lock via cxl_adapter_context_lock() in the eeh callback cxl_pci_error_detected() once all the virtual AFU PHBs are notified and their contexts detached. The context-lock is released in cxl_pci_slot_reset() after the adapter is successfully reconfigured and before the we call the slot_reset callback on slice attached device-drivers. Fixes: 70b565bbdb91 ("cxl: Prevent adapter reset if an active context exists") Cc: stable@vger.kernel.org # v4.9+ Reported-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Signed-off-by: Vaibhav Jain <vaibhav@linux.vnet.ibm.com> Acked-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com> Reviewed-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Tested-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-04-19cxl: Enable PCI device IDs for future IBM CXL adaptersMatthew R. Ochs1-0/+2
Add support for future IBM Coherent Accelerator (CXL) devices with an IDs of 0x0623 and 0x0628. Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com> Acked-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-04-13cxl: Add psl9 specific codeChristophe Lombard9-74/+751
The new Coherent Accelerator Interface Architecture, level 2, for the IBM POWER9 brings new content and features: - POWER9 Service Layer - Registers - Radix mode - Process element entry - Dedicated-Shared Process Programming Model - Translation Fault Handling - CAPP - Memory Context ID If a valid mm_struct is found the memory context id is used for each transaction associated with the process handle. The PSL uses the context ID to find the corresponding process element. Signed-off-by: Christophe Lombard <clombard@linux.vnet.ibm.com> Acked-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com> [mpe: Fixup comment formatting, unsplit long strings] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-04-13cxl: Isolate few psl8 specific callsChristophe Lombard5-56/+116
Point out the specific Coherent Accelerator Interface Architecture, level 1, registers. Code and functions specific to PSL8 (CAIA1) must be framed. Signed-off-by: Christophe Lombard <clombard@linux.vnet.ibm.com> Acked-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com> [mpe: Don't split long strings, it makes them hard to grep for] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-04-13cxl: Rename some psl8 specific functionsChristophe Lombard6-54/+54
Rename a few functions, changing the '_psl' suffix to '_psl8', to make clear that the implementation is psl8 specific. Those functions will have an equivalent implementation for the psl9 in a later patch. Signed-off-by: Christophe Lombard <clombard@linux.vnet.ibm.com> Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Acked-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-04-13cxl: Update implementation service layerChristophe Lombard6-59/+110
The service layer API (in cxl.h) lists some low-level functions whose implementation is different on PSL8, PSL9 and XSL: - Init implementation for the adapter and the afu. - Invalidate TLB/SLB. - Attach process for dedicated/directed models. - Handle psl interrupts. - Debug registers for the adapter and the afu. - Traces. Each environment implements its own functions, and the common code uses them through function pointers, defined in cxl_service_layer_ops. Signed-off-by: Christophe Lombard <clombard@linux.vnet.ibm.com> Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Acked-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-04-13cxl: Keep track of mm struct associated with a contextChristophe Lombard6-90/+61
The mm_struct corresponding to the current task is acquired each time an interrupt is raised. So to simplify the code, we only get the mm_struct when attaching an AFU context to the process. The mm_count reference is increased to ensure that the mm_struct can't be freed. The mm_struct will be released when the context is detached. A reference on mm_users is not kept to avoid a circular dependency if the process mmaps its cxl mmio and forget to unmap before exiting. The field glpid (pid of the group leader associated with the pid), of the structure cxl_context, is removed because it's no longer useful. Signed-off-by: Christophe Lombard <clombard@linux.vnet.ibm.com> Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Acked-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-04-13cxl: Remove unused values in bare-metal environment.Christophe Lombard3-24/+7
The two previously fields pid and tid, located in the structure cxl_irq_info, are only used in the guest environment. To avoid confusion, it's not necessary to fill the fields in the bare-metal environment. Pid_tid is now renamed to 'reserved' to avoid undefined behavior on bare-metal. The PSL Process and Thread Identification Register (CXL_PSL_PID_TID_An) is only used when attaching a dedicated process for PSL8 only. This register goes away in CAIA2. Signed-off-by: Christophe Lombard <clombard@linux.vnet.ibm.com> Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Acked-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-04-13cxl: Read vsec perst load imageChristophe Lombard1-0/+1
This bit is used to cause a flash image load for programmable CAIA-compliant implementation. If this bit is set to ‘0’, a power cycle of the adapter is required to load a programmable CAIA-com- pliant implementation from flash. This field will be used by the following patches. Signed-off-by: Christophe Lombard <clombard@linux.vnet.ibm.com> Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Acked-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-03-24treewide: Fix typos in printkMasanari Iida1-1/+1
This patch fix some spelling typos found in printk. [jkosina@suse.cz: drop arch/arm64/kernel/hibernate.c that was already in place] Signed-off-by: Masanari Iida <standby24x7@gmail.com> Acked-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2017-03-20cxl: Route eeh events to all slices for pci_channel_io_perm_failure stateVaibhav Jain1-7/+6
Fix a boundary condition where in some cases an eeh event with state == pci_channel_io_perm_failure wont be passed on to a driver attached to the virtual PCI device associated with a slice. This will happen in case the slice just before (n-1) doesn't have any vPHB bus associated with it, that results in an early return from cxl_pci_error_detected() callback. With state == pci_channel_io_perm_failure, the adapter will be removed irrespective of the return value of cxl_vphb_error_detected(). So we now always return PCI_ERS_RESULT_DISCONNECTED for this case i.e even if the AFU isn't using a vPHB (currently returns PCI_ERS_RESULT_NONE). Fixes: e4f5fc001a6("cxl: Do not create vPHB if there are no AFU configuration records") Signed-off-by: Vaibhav Jain <vaibhav@linux.vnet.ibm.com> Reviewed-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Acked-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-03-02sched/headers: Prepare to move the get_task_struct()/put_task_struct() and ↵Ingo Molnar1-0/+2
related APIs from <linux/sched.h> to <linux/sched/task.h> But first update usage sites with the new header dependency. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-02sched/headers: Prepare to move signal wakeup & sigpending methods from ↵Ingo Molnar2-2/+2
<linux/sched.h> into <linux/sched/signal.h> Fix up affected files that include this signal functionality via sched.h. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-02sched/headers: Prepare for new header dependencies before moving code to ↵Ingo Molnar1-0/+1
<linux/sched/mm.h> We are going to split <linux/sched/mm.h> out of <linux/sched.h>, which will have to be picked up from other headers and a couple of .c files. Create a trivial placeholder <linux/sched/mm.h> file that just maps to <linux/sched.h> to make this patch obviously correct and bisectable. The APIs that are going to be moved first are: mm_alloc() __mmdrop() mmdrop() mmdrop_async_fn() mmdrop_async() mmget_not_zero() mmput() mmput_async() get_task_mm() mm_access() mm_release() Include the new header in the files that are going to need it. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-02sched/headers: Prepare for new header dependencies before moving code to ↵Ingo Molnar1-0/+1
<linux/sched/clock.h> We are going to split <linux/sched/clock.h> out of <linux/sched.h>, which will have to be picked up from other headers and .c files. Create a trivial placeholder <linux/sched/clock.h> file that just maps to <linux/sched.h> to make this patch obviously correct and bisectable. Include the new header in the files that are going to need it. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-01Merge tag 'powerpc-4.11-2' of ↵Linus Torvalds4-10/+27
git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull more powerpc updates from Michael Ellerman: "Highlights include: - an update of the disassembly code used by xmon to the latest versions in binutils. We've received permission from all the authors of the relevant binutils changes to relicense their changes to the relevant files from GPLv3 to GPLv2, for inclusion in Linux. Thanks to Peter Bergner for doing the leg work to get permission from everyone. - addition of the "architected" Power9 CPU table entry, allowing us to boot in Power9 architected mode under a hypervisor. - updates to the Power9 PMU code. - implementation of clear_bit_unlock_is_negative_byte() to optimise unlock_page(). - Freescale updates from Scott: "Highlights include 8xx breakpoints and perf, t1042rdb display support, and board updates." Thanks to: Al Viro, Andrew Donnellan, Aneesh Kumar K.V, Balbir Singh, Douglas Miller, Frédéric Weisbecker, Gavin Shan, Madhavan Srinivasan, Michael Roth, Nathan Fontenot, Naveen N. Rao, Nicholas Piggin, Peter Bergner, Paul E. McKenney, Rashmica Gupta, Russell Currey, Sahil Mehta, Stewart Smith" * tag 'powerpc-4.11-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (48 commits) powerpc: Remove leftover cputime_to_nsecs call causing build error powerpc/mm/hash: Always clear UPRT and Host Radix bits when setting up CPU powerpc/optprobes: Fix TOC handling in optprobes trampoline powerpc/pseries: Advertise Hot Plug Event support to firmware cxl: fix nested locking hang during EEH hotplug powerpc/xmon: Dump memory in CPU endian format powerpc/pseries: Revert 'Auto-online hotplugged memory' powerpc/powernv: Make PCI non-optional powerpc/64: Implement clear_bit_unlock_is_negative_byte() powerpc/powernv: Remove unused variable in pnv_pci_sriov_disable() powerpc/kernel: Remove error message in pcibios_setup_phb_resources() powerpc/mm: Fix typo in set_pte_at() pci/hotplug/pnv-php: Disable MSI and PCI device properly pci/hotplug/pnv-php: Disable surprise hotplug capability on conflicts pci/hotplug/pnv-php: Remove WARN_ON() in pnv_php_put_slot() powerpc: Add POWER9 architected mode to cputable powerpc/perf: use is_kernel_addr macro in perf_get_misc_flags() powerpc/perf: Avoid FAB_*_MATCH checks for power9 powerpc/perf: Add restrictions to PMC5 in power9 DD1 powerpc/perf: Use Instruction Counter value ...
2017-02-25mm, fs: reduce fault, page_mkwrite, and pfn_mkwrite to take only vmfDave Jiang1-1/+2
->fault(), ->page_mkwrite(), and ->pfn_mkwrite() calls do not need to take a vma and vmf parameter when the vma already resides in vmf. Remove the vma parameter to simplify things. [arnd@arndb.de: fix ARM build] Link: http://lkml.kernel.org/r/20170125223558.1451224-1-arnd@arndb.de Link: http://lkml.kernel.org/r/148521301778.19116.10840599906674778980.stgit@djiang5-desk3.ch.intel.com Signed-off-by: Dave Jiang <dave.jiang@intel.com> Signed-off-by: Arnd Bergmann <arnd@arndb.de> Reviewed-by: Ross Zwisler <ross.zwisler@linux.intel.com> Cc: Theodore Ts'o <tytso@mit.edu> Cc: Darrick J. Wong <darrick.wong@oracle.com> Cc: Matthew Wilcox <mawilcox@microsoft.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Jan Kara <jack@suse.com> Cc: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-21cxl: fix nested locking hang during EEH hotplugAndrew Donnellan4-10/+27
Commit 14a3ae34bfd0 ("cxl: Prevent read/write to AFU config space while AFU not configured") introduced a rwsem to fix an invalid memory access that occurred when someone attempts to access the config space of an AFU on a vPHB whilst the AFU is deconfigured, such as during EEH recovery. It turns out that it's possible to run into a nested locking issue when EEH recovery fails and a full device hotplug is required. cxl_pci_error_detected() deconfigures the AFU, taking a writer lock on configured_rwsem. When EEH recovery fails, the EEH code calls pci_hp_remove_devices() to remove the device, which in turn calls cxl_remove() -> cxl_pci_remove_afu() -> pci_deconfigure_afu(), which tries to grab the writer lock that's already held. Standard rwsem semantics don't express what we really want to do here and don't allow for nested locking. Fix this by replacing the rwsem with an atomic_t which we can control more finely. Allow the AFU to be locked multiple times so long as there are no readers. Fixes: 14a3ae34bfd0 ("cxl: Prevent read/write to AFU config space while AFU not configured") Cc: stable@vger.kernel.org # v4.9+ Signed-off-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Acked-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-02-03cxl: Fix build when CONFIG_DEBUG_FS=nAndrew Donnellan2-5/+57
Stub out the debugfs functions so that the build doesn't break when CONFIG_DEBUG_FS=n. Reported-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Acked-by: Ian Munsie <imunsie@au1.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-01-25cxl: Prevent read/write to AFU config space while AFU not configuredAndrew Donnellan4-23/+35
During EEH recovery, we deconfigure all AFUs whilst leaving the corresponding vPHB and virtual PCI device in place. If something attempts to interact with the AFU's PCI config space (e.g. running lspci) after the AFU has been deconfigured and before it's reconfigured, cxl_pcie_{read,write}_config() will read invalid values from the deconfigured struct cxl_afu and proceed to Oops when they try to dereference pointers that have been set to NULL during deconfiguration. Add a rwsem to struct cxl_afu so we can prevent interaction with config space while the AFU is deconfigured. Reported-by: Pradipta Ghosh <pradghos@in.ibm.com> Suggested-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com> Cc: stable@vger.kernel.org # v4.9+ Signed-off-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Signed-off-by: Vaibhav Jain <vaibhav@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-01-25cxl: Force psl data-cache flush during device shutdownVaibhav Jain1-0/+3
This change adds a force psl data cache flush during device shutdown callback. This should reduce a possibility of psl holding a dirty cache line while the CAPP is being reinitialized, which may result in a UE [load/store] machine check error. Signed-off-by: Vaibhav Jain <vaibhav@linux.vnet.ibm.com> Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Acked-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-01-25cxl: Drop unused header asm/pnv-pci.hGreg Kurz1-1/+0
The kernel API does not use anything from this header file. Signed-off-by: Greg Kurz <groug@kaod.org> Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Acked-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-12-16Merge tag 'powerpc-4.10-1' of ↵Linus Torvalds10-49/+160
git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc updates from Michael Ellerman: "Highlights include: - Support for the kexec_file_load() syscall, which is a prereq for secure and trusted boot. - Prevent kernel execution of userspace on P9 Radix (similar to SMEP/PXN). - Sort the exception tables at build time, to save time at boot, and store them as relative offsets to save space in the kernel image & memory. - Allow building the kernel with thin archives, which should allow us to build an allyesconfig once some other fixes land. - Build fixes to allow us to correctly rebuild when changing the kernel endian from big to little or vice versa. - Plumbing so that we can avoid doing a full mm TLB flush on P9 Radix. - Initial stack protector support (-fstack-protector). - Support for dumping the radix (aka. Linux) and hash page tables via debugfs. - Fix an oops in cxl coredump generation when cxl_get_fd() is used. - Freescale updates from Scott: "Highlights include 8xx hugepage support, qbman fixes/cleanup, device tree updates, and some misc cleanup." - Many and varied fixes and minor enhancements as always. Thanks to: Alexey Kardashevskiy, Andrew Donnellan, Aneesh Kumar K.V, Anshuman Khandual, Anton Blanchard, Balbir Singh, Bartlomiej Zolnierkiewicz, Christophe Jaillet, Christophe Leroy, Denis Kirjanov, Elimar Riesebieter, Frederic Barrat, Gautham R. Shenoy, Geliang Tang, Geoff Levand, Jack Miller, Johan Hovold, Lars-Peter Clausen, Libin, Madhavan Srinivasan, Michael Neuling, Nathan Fontenot, Naveen N. Rao, Nicholas Piggin, Pan Xinhui, Peter Senna Tschudin, Rashmica Gupta, Rui Teng, Russell Currey, Scott Wood, Simon Guo, Suraj Jitindar Singh, Thiago Jung Bauermann, Tobias Klauser, Vaibhav Jain" [ And thanks to Michael, who took time off from a new baby to get this pull request done. - Linus ] * tag 'powerpc-4.10-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (174 commits) powerpc/fsl/dts: add FMan node for t1042d4rdb powerpc/fsl/dts: add sg_2500_aqr105_phy4 alias on t1024rdb powerpc/fsl/dts: add QMan and BMan nodes on t1024 powerpc/fsl/dts: add QMan and BMan nodes on t1023 soc/fsl/qman: test: use DEFINE_SPINLOCK() powerpc/fsl-lbc: use DEFINE_SPINLOCK() powerpc/8xx: Implement support of hugepages powerpc: get hugetlbpage handling more generic powerpc: port 64 bits pgtable_cache to 32 bits powerpc/boot: Request no dynamic linker for boot wrapper soc/fsl/bman: Use resource_size instead of computation soc/fsl/qe: use builtin_platform_driver powerpc/fsl_pmc: use builtin_platform_driver powerpc/83xx/suspend: use builtin_platform_driver powerpc/ftrace: Fix the comments for ftrace_modify_code powerpc/perf: macros for power9 format encoding powerpc/perf: power9 raw event format encoding powerpc/perf: update attribute_group data structure powerpc/perf: factor out the event format field powerpc/mm/iommu, vfio/spapr: Put pages on VFIO container shutdown ...
2016-12-15mm: use vmf->address instead of of vmf->virtual_addressJan Kara1-3/+2
Every single user of vmf->virtual_address typed that entry to unsigned long before doing anything with it so the type of virtual_address does not really provide us any additional safety. Just use masked vmf->address which already has the appropriate type. Link: http://lkml.kernel.org/r/1479460644-25076-3-git-send-email-jack@suse.cz Signed-off-by: Jan Kara <jack@suse.cz> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Ross Zwisler <ross.zwisler@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-11-25cxl: drop duplicate header sched.hGeliang Tang1-1/+0
Drop duplicate header sched.h from native.c. Signed-off-by: Geliang Tang <geliangtang@gmail.com> Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-11-23cxl: Fix coccinelle warningsAndrew Donnellan4-6/+8
Fix the following coccinelle warnings: drivers/misc/cxl/debugfs.c:46:0-23: WARNING: fops_io_x64 should be defined with DEFINE_DEBUGFS_ATTRIBUTE drivers/misc/cxl/guest.c:890:5-26: WARNING: Comparison to bool drivers/misc/cxl/irq.c:107:3-23: WARNING: Assignment of bool to 0/1 drivers/misc/cxl/native.c:57:2-3: Unneeded semicolon drivers/misc/cxl/native.c:170:2-3: Unneeded semicolon Signed-off-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Acked-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com> Reviewed-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Acked-by: Ian Munsie <imunsie@au1.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-11-18cxl: Fix coredump generation when cxl_get_fd() is usedFrederic Barrat4-31/+135
If a process dumps core while owning a cxl file descriptor obtained from an AFU driver (e.g. cxlflash) through the cxl_get_fd() API, the following error occurs: [ 868.027591] Unable to handle kernel paging request for data at address ... [ 868.027778] Faulting instruction address: 0xc00000000035edb0 cpu 0x8c: Vector: 300 (Data Access) at [c000003c688275e0] pc: c00000000035edb0: elf_core_dump+0xd60/0x1300 lr: c00000000035ed80: elf_core_dump+0xd30/0x1300 sp: c000003c68827860 msr: 9000000100009033 dar: c dsisr: 40000000 current = 0xc000003c68780000 paca = 0xc000000001b73200 softe: 0 irq_happened: 0x01 pid = 46725, comm = hxesurelock enter ? for help [c000003c68827a60] c00000000036948c do_coredump+0xcec/0x11e0 [c000003c68827c20] c0000000000ce9e0 get_signal+0x540/0x7b0 [c000003c68827d10] c000000000017354 do_signal+0x54/0x2b0 [c000003c68827e00] c00000000001777c do_notify_resume+0xbc/0xd0 [c000003c68827e30] c000000000009838 ret_from_except_lite+0x64/0x68 --- Exception: 300 (Data Access) at 00003fff98ad2918 The root cause is that the address_space structure for the file doesn't define a 'host' member. When cxl allocates a file descriptor, it's using the anonymous inode to back the file, but allocates a private address_space for each context. The private address_space allows to track memory allocation for each context. cxl doesn't define the 'host' member of the address space, i.e. the inode. We don't want to define it as the anonymous inode, since there's no longer a 1-to-1 relation between address_space and inode. To fix it, instead of using the anonymous inode, we introduce a simple pseudo filesystem so that cxl can allocate its own inodes. So we now have one inode for each file and address_space. The pseudo filesystem is only mounted on the first allocation of a file descriptor by cxl_get_fd(). Tested with cxlflash. Signed-off-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com> Reviewed-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-11-18cxl: Do adapter fence check before handling afu interruptVaibhav Jain1-3/+12
If an afu interrupt is in flight when an eeh error is triggered the control still reaches the function native_irq_multiplexed and the PE-Handle read from the CXL_PSL_PEHandle_An register is 0xffff. The function then erroneously assumes that the interrupt belonged to a detached context and generates a warning with full stack dump in the kernel log complaining: "Unable to demultiplex CXL PSL IRQ for PE 65535 DSISR ffffffff DAR ffffffff. (Possible AFU HW issue - was a term/remove acked with outstanding transactions" To fix this the patch adds new code to the function native_irq_multiplexed function to compares the read value of register CXL_PSL_PEHandle_An to ~0ULL. If true then logs a warning message saying that the interrupt is being ignored and returns IRQ_HANDLED from the irq handler. Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Acked-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com> Acked-by: Ian Munsie <imunsie@au1.ibm.com> Signed-off-by: Vaibhav Jain <vaibhav@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-11-18cxl: Fix error handling in _cxl_pci_associate_default_context()Christophe Jaillet2-2/+2
'cxl_dev_context_init()' returns an error pointer in case of error, not NULL. So test it with IS_ERR. Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr> Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Acked-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com> Acked-by: Ian Munsie <imunsie@au1.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-11-18cxl: Fix error handling in _cxl_cx4_setup_msi_irqs()Christophe Jaillet1-1/+1
'cxl_dev_context_init()' returns an error pointer in case of error, not NULL. So test it with IS_ERR. Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr> Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Acked-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com> Acked-by: Ian Munsie <imunsie@au1.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-11-18cxl: Fix memory allocation failure testChristophe Jaillet1-5/+2
'cxl_context_alloc()' does not return an error pointer. It is just a shortcut for a call to 'kzalloc' with 'sizeof(struct cxl_context)' as the size parameter. So its return value should be compared with NULL. While fixing it, simplify a bit the code. Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr> Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Acked-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com> Acked-by: Ian Munsie <imunsie@au1.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-10-24cxl: Fix leaking pid refs in some error pathsVaibhav Jain2-9/+15
In some error paths in functions cxl_start_context and afu_ioctl_start_work pid references to the current & group-leader tasks can leak after they are taken. This patch fixes these error paths to release these pid references before exiting the error path. Fixes: 7b8ad495d592 ("cxl: Fix DSI misses when the context owning task exits") Cc: stable@vger.kernel.org # v4.5+ Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Reported-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com> Signed-off-by: Vaibhav Jain <vaibhav@linux.vnet.ibm.com> Acked-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-10-19cxl: Prevent adapter reset if an active context existsVaibhav Jain8-5/+116
This patch prevents resetting the cxl adapter via sysfs in presence of one or more active cxl_context on it. This protects against an unrecoverable error caused by PSL owning a dirty cache line even after reset and host tries to touch the same cache line. In case a force reset of the card is required irrespective of any active contexts, the int value -1 can be stored in the 'reset' sysfs attribute of the card. The patch introduces a new atomic_t member named contexts_num inside struct cxl that holds the number of active context attached to the card , which is checked against '0' before proceeding with the reset. To prevent against a race condition where a context is activated just after reset check is performed, the contexts_num is atomically set to '-1' after reset-check to indicate that no more contexts can be activated on the card anymore. Before activating a context we atomically test if contexts_num is non-negative and if so, increment its value by one. In case the value of contexts_num is negative then it indicates that the card is about to be reset and context activation is error-ed out at that point. Fixes: 62fa19d4b4fd ("cxl: Add ability to reset the card") Cc: stable@vger.kernel.org # v4.0+ Acked-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com> Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Signed-off-by: Vaibhav Jain <vaibhav@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-10-04cxl: replace loop with for_each_child_of_node(), remove unneeded of_node_put()Andrew Donnellan1-5/+3
Rewrite the cxl_guest_init_afu() loop in cxl_of_probe() to use for_each_child_of_node() rather than a hand-coded for loop. Remove the useless of_node_put(afu_np) call after the loop, where it's guaranteed that afu_np == NULL. Reported-by: SF Markus Elfring <elfring@users.sourceforge.net> Reported-by: Julia Lawall <julia.lawall@lip6.fr> Signed-off-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Reviewed-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-10-04cxl: Flush PSL cache before resetting the adapterFrederic Barrat3-1/+39
If the capi link is going down while the PSL owns a dirty cache line, any access from the host for that data could lead to an Uncorrectable Error. So when resetting the capi adapter through sysfs, make sure the PSL cache is flushed. It won't help if there are any active Process Elements on the card, as the cache would likely get new dirty cache lines immediately, but if resetting an idle adapter, it should avoid any bad surprises from data left over from terminated Process Elements. Signed-off-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com> Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Acked-by: Ian Munsie <imunsie@au1.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>