summaryrefslogtreecommitdiff
path: root/drivers/misc/cxl
AgeCommit message (Collapse)AuthorFilesLines
2019-07-19Merge branch 'work.mount0' of ↵Linus Torvalds1-9/+4
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull vfs mount updates from Al Viro: "The first part of mount updates. Convert filesystems to use the new mount API" * 'work.mount0' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (63 commits) mnt_init(): call shmem_init() unconditionally constify ksys_mount() string arguments don't bother with registering rootfs init_rootfs(): don't bother with init_ramfs_fs() vfs: Convert smackfs to use the new mount API vfs: Convert selinuxfs to use the new mount API vfs: Convert securityfs to use the new mount API vfs: Convert apparmorfs to use the new mount API vfs: Convert openpromfs to use the new mount API vfs: Convert xenfs to use the new mount API vfs: Convert gadgetfs to use the new mount API vfs: Convert oprofilefs to use the new mount API vfs: Convert ibmasmfs to use the new mount API vfs: Convert qib_fs/ipathfs to use the new mount API vfs: Convert efivarfs to use the new mount API vfs: Convert configfs to use the new mount API vfs: Convert binfmt_misc to use the new mount API convenience helper: get_tree_single() convenience helper get_tree_nodev() vfs: Kill sget_userns() ...
2019-07-12Merge tag 'driver-core-5.3-rc1' of ↵Linus Torvalds2-34/+17
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core Pull driver core and debugfs updates from Greg KH: "Here is the "big" driver core and debugfs changes for 5.3-rc1 It's a lot of different patches, all across the tree due to some api changes and lots of debugfs cleanups. Other than the debugfs cleanups, in this set of changes we have: - bus iteration function cleanups - scripts/get_abi.pl tool to display and parse Documentation/ABI entries in a simple way - cleanups to Documenatation/ABI/ entries to make them parse easier due to typos and other minor things - default_attrs use for some ktype users - driver model documentation file conversions to .rst - compressed firmware file loading - deferred probe fixes All of these have been in linux-next for a while, with a bunch of merge issues that Stephen has been patient with me for" * tag 'driver-core-5.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (102 commits) debugfs: make error message a bit more verbose orangefs: fix build warning from debugfs cleanup patch ubifs: fix build warning after debugfs cleanup patch driver: core: Allow subsystems to continue deferring probe drivers: base: cacheinfo: Ensure cpu hotplug work is done before Intel RDT arch_topology: Remove error messages on out-of-memory conditions lib: notifier-error-inject: no need to check return value of debugfs_create functions swiotlb: no need to check return value of debugfs_create functions ceph: no need to check return value of debugfs_create functions sunrpc: no need to check return value of debugfs_create functions ubifs: no need to check return value of debugfs_create functions orangefs: no need to check return value of debugfs_create functions nfsd: no need to check return value of debugfs_create functions lib: 842: no need to check return value of debugfs_create functions debugfs: provide pr_fmt() macro debugfs: log errors when something goes wrong drivers: s390/cio: Fix compilation warning about const qualifiers drivers: Add generic helper to match by of_node driver_find_device: Unify the match function with class_find_device() bus_find_device: Unify the match callback with class_find_device ...
2019-06-18cxl: no need to check return value of debugfs_create functionsGreg Kroah-Hartman2-34/+17
When calling debugfs functions, there is no need to ever check the return value. The function can work or not, but the code logic should never do something different based on this. Because there's no need to check, also make the return value of the local debugfs_create_io_x64() call void, as no one ever did anything with the return value (as they did not need to.) And make the cxl_debugfs_* calls return void as no one was even checking their return value at all. Cc: linuxppc-dev@lists.ozlabs.org Acked-by: Andrew Donnellan <ajd@linux.ibm.com> Reviewed-by: Frederic Barrat <fbarrat@linux.ibm.com> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-09Merge 5.2-rc4 into char-misc-nextGreg Kroah-Hartman21-100/+21
We want the char/misc driver fixes in here as well. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152Thomas Gleixner20-100/+20
Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation either version 2 of the license or at your option any later version extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 3029 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-25vfs: Convert cxl to use the new mount APIDavid Howells1-4/+4
Convert the cxl filesystem to the new internal mount API as the old one will be obsoleted and removed. This allows greater flexibility in communication of mount parameters between userspace, the VFS and the filesystem. See Documentation/filesystems/mount_api.txt for more information. Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Acked-by: Frederic Barrat <fbarrat@linux.ibm.com> cc: linuxppc-dev@lists.ozlabs.org Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2019-05-25mount_pseudo(): drop 'name' argument, switch to d_make_root()Al Viro1-2/+1
Once upon a time we used to set ->d_name of e.g. pipefs root so that d_path() on pipes would work. These days it's completely pointless - dentries of pipes are not even connected to pipefs root. However, mount_pseudo() had set the root dentry name (passed as the second argument) and callers kept inventing names to pass to it. Including those that didn't *have* any non-root dentries to start with... All of that had been pointless for about 8 years now; it's time to get rid of that cargo-culting... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2019-05-24misc: remove redundant 'default n' from Kconfig-sBartlomiej Zolnierkiewicz1-3/+0
'default n' is the default value for any bool or tristate Kconfig setting so there is no need to write it explicitly. Also since commit f467c5640c29 ("kconfig: only write '# CONFIG_FOO is not set' for visible symbols") the Kconfig behavior is the same regardless of 'default n' being present or not: ... One side effect of (and the main motivation for) this change is making the following two definitions behave exactly the same: config FOO bool config FOO bool default n With this change, neither of these will generate a '# CONFIG_FOO is not set' line (assuming FOO isn't selected/implied). That might make it clearer to people that a bare 'default n' is redundant. ... Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> Acked-by: Frederic Barrat <fbarrat@linux.ibm.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-21treewide: Add SPDX license identifier - Makefile/KconfigThomas Gleixner1-0/+1
Add SPDX license identifiers to all Make/Kconfig files which: - Have no license information of any form These files fall under the project license, GPL v2 only. The resulting SPDX license identifier is: GPL-2.0-only Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-20cxl: don't bother with dentry_operationsAl Viro1-5/+1
default will do Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2019-04-21powerpc/mm/hash64: Map all the kernel regions in the same 0xc rangeAneesh Kumar K.V1-1/+1
This patch maps vmalloc, IO and vmemap regions in the 0xc address range instead of the current 0xd and 0xf range. This brings the mapping closer to radix translation mode. With hash 64K page size each of this region is 512TB whereas with 4K config we are limited by the max page table range of 64TB and hence there regions are of 16TB size. The kernel mapping is now: On 4K hash kernel_region_map_size = 16TB kernel vmalloc start = 0xc000100000000000 kernel IO start = 0xc000200000000000 kernel vmemmap start = 0xc000300000000000 64K hash, 64K radix and 4k radix: kernel_region_map_size = 512TB kernel vmalloc start = 0xc008000000000000 kernel IO start = 0xc00a000000000000 kernel vmemmap start = 0xc00c000000000000 Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-21Merge branch 'topic/dma' into nextMichael Ellerman1-2/+1
Merge hch's big DMA rework series. This is in a topic branch in case he wants to merge it to minimise conflicts.
2019-02-18powerpc/dma: remove set_dma_offsetChristoph Hellwig1-1/+1
There is no good reason for this helper, just opencode it. Signed-off-by: Christoph Hellwig <hch@lst.de> Tested-by: Christian Zigotzky <chzigotzky@xenosoft.de> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-18powerpc/dma: use the generic direct mapping bypassChristoph Hellwig1-1/+0
Now that we've switched all the powerpc nommu and swiotlb methods to use the generic dma_direct_* calls we can remove these ops vectors entirely and rely on the common direct mapping bypass that avoids indirect function calls entirely. This also allows to remove a whole lot of boilerplate code related to setting up these operations. Signed-off-by: Christoph Hellwig <hch@lst.de> Tested-by: Christian Zigotzky <chzigotzky@xenosoft.de> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-01-30cxl: Wrap iterations over afu slices inside 'afu_list_lock'Vaibhav Jain2-9/+32
Within cxl module, iteration over array 'adapter->afu' may be racy at few points as it might be simultaneously read during an EEH and its contents being set to NULL while driver is being unloaded or unbound from the adapter. This might result in a NULL pointer to 'struct afu' being de-referenced during an EEH thereby causing a kernel oops. This patch fixes this by making sure that all access to the array 'adapter->afu' is wrapped within the context of spin-lock 'adapter->afu_list_lock'. Fixes: 9e8df8a21963 ("cxl: EEH support") Cc: stable@vger.kernel.org # v4.3+ Acked-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Acked-by: Frederic Barrat <fbarrat@linux.ibm.com> Acked-by: Christophe Lombard <clombard@linux.vnet.ibm.com> Signed-off-by: Vaibhav Jain <vaibhav@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-20cxl: drop the dma_set_mask callback from vphbChristoph Hellwig1-12/+0
The CXL code never even looks at the dma mask, so there is no good reason for this sanity check. Remove it because it gets in the way of the dma ops refactoring. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-11-26cxl: Use device_type helpers to access the node typeRob Herring1-3/+1
Remove directly accessing device_node.type pointer and use the accessors instead. This will eventually allow removing the type pointer. Signed-off-by: Rob Herring <robh@kernel.org> Acked-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-10-11misc: cxl: Fix possible null pointer dereferencezhong jiang1-2/+0
It is not safe to dereference an object before a null test. It is not needed and just remove them. Ftrace can be used instead. Signed-off-by: zhong jiang <zhongjiang@huawei.com> Acked-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Acked-by: Frederic Barrat <fbarrat@linux.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-14misc: Convert to using %pOFn instead of device_node.nameRob Herring1-2/+2
In preparation to remove the node name pointer from struct device_node, convert printf users to use the %pOFn format specifier. Cc: Frederic Barrat <fbarrat@linux.vnet.ibm.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: linuxppc-dev@lists.ozlabs.org Signed-off-by: Rob Herring <robh@kernel.org> Acked-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-08-17Merge branch 'akpm' (patches from Andrew)Linus Torvalds1-1/+1
Merge updates from Andrew Morton: - a few misc things - a few Y2038 fixes - ntfs fixes - arch/sh tweaks - ocfs2 updates - most of MM * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (111 commits) mm/hmm.c: remove unused variables align_start and align_end fs/userfaultfd.c: remove redundant pointer uwq mm, vmacache: hash addresses based on pmd mm/list_lru: introduce list_lru_shrink_walk_irq() mm/list_lru.c: pass struct list_lru_node* as an argument to __list_lru_walk_one() mm/list_lru.c: move locking from __list_lru_walk_one() to its caller mm/list_lru.c: use list_lru_walk_one() in list_lru_walk_node() mm, swap: make CONFIG_THP_SWAP depend on CONFIG_SWAP mm/sparse: delete old sparse_init and enable new one mm/sparse: add new sparse_init_nid() and sparse_init() mm/sparse: move buffer init/fini to the common place mm/sparse: use the new sparse buffer functions in non-vmemmap mm/sparse: abstract sparse buffer allocations mm/hugetlb.c: don't zero 1GiB bootmem pages mm, page_alloc: double zone's batchsize mm/oom_kill.c: document oom_lock mm/hugetlb: remove gigantic page support for HIGHMEM mm, oom: remove sleep from under oom_lock kernel/dma: remove unsupported gfp_mask parameter from dma_alloc_from_contiguous() mm/cma: remove unsupported gfp_mask parameter from cma_alloc() ...
2018-08-17mm: convert return type of handle_mm_fault() caller to vm_fault_tSouptick Joarder1-1/+1
Use new return type vm_fault_t for fault handler. For now, this is just documenting that the function returns a VM_FAULT value rather than an errno. Once all instances are converted, vm_fault_t will become a distinct type. Ref-> commit 1c8f422059ae ("mm: change return type to vm_fault_t") In this patch all the caller of handle_mm_fault() are changed to return vm_fault_t type. Link: http://lkml.kernel.org/r/20180617084810.GA6730@jordon-HP-15-Notebook-PC Signed-off-by: Souptick Joarder <jrdr.linux@gmail.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Richard Henderson <rth@twiddle.net> Cc: Tony Luck <tony.luck@intel.com> Cc: Matt Turner <mattst88@gmail.com> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: Russell King <linux@armlinux.org.uk> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Richard Kuo <rkuo@codeaurora.org> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Michal Simek <monstr@monstr.eu> Cc: James Hogan <jhogan@kernel.org> Cc: Ley Foon Tan <lftan@altera.com> Cc: Jonas Bonn <jonas@southpole.se> Cc: James E.J. Bottomley <jejb@parisc-linux.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Palmer Dabbelt <palmer@sifive.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Cc: David S. Miller <davem@davemloft.net> Cc: Richard Weinberger <richard@nod.at> Cc: Guan Xuetao <gxt@pku.edu.cn> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: "Levin, Alexander (Sasha Levin)" <alexander.levin@verizon.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-08-17Merge tag 'powerpc-4.19-1' of ↵Linus Torvalds15-705/+75
git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc updates from Michael Ellerman: "Notable changes: - A fix for a bug in our page table fragment allocator, where a page table page could be freed and reallocated for something else while still in use, leading to memory corruption etc. The fix reuses pt_mm in struct page (x86 only) for a powerpc only refcount. - Fixes to our pkey support. Several are user-visible changes, but bring us in to line with x86 behaviour and/or fix outright bugs. Thanks to Florian Weimer for reporting many of these. - A series to improve the hvc driver & related OPAL console code, which have been seen to cause hardlockups at times. The hvc driver changes in particular have been in linux-next for ~month. - Increase our MAX_PHYSMEM_BITS to 128TB when SPARSEMEM_VMEMMAP=y. - Remove Power8 DD1 and Power9 DD1 support, neither chip should be in use anywhere other than as a paper weight. - An optimised memcmp implementation using Power7-or-later VMX instructions - Support for barrier_nospec on some NXP CPUs. - Support for flushing the count cache on context switch on some IBM CPUs (controlled by firmware), as a Spectre v2 mitigation. - A series to enhance the information we print on unhandled signals to bring it into line with other arches, including showing the offending VMA and dumping the instructions around the fault. Thanks to: Aaro Koskinen, Akshay Adiga, Alastair D'Silva, Alexey Kardashevskiy, Alexey Spirkov, Alistair Popple, Andrew Donnellan, Aneesh Kumar K.V, Anju T Sudhakar, Arnd Bergmann, Bartosz Golaszewski, Benjamin Herrenschmidt, Bharat Bhushan, Bjoern Noetel, Boqun Feng, Breno Leitao, Bryant G. Ly, Camelia Groza, Christophe Leroy, Christoph Hellwig, Cyril Bur, Dan Carpenter, Daniel Klamt, Darren Stevens, Dave Young, David Gibson, Diana Craciun, Finn Thain, Florian Weimer, Frederic Barrat, Gautham R. Shenoy, Geert Uytterhoeven, Geoff Levand, Guenter Roeck, Gustavo Romero, Haren Myneni, Hari Bathini, Joel Stanley, Jonathan Neuschäfer, Kees Cook, Madhavan Srinivasan, Mahesh Salgaonkar, Markus Elfring, Mathieu Malaterre, Mauro S. M. Rodrigues, Michael Hanselmann, Michael Neuling, Michael Schmitz, Mukesh Ojha, Murilo Opsfelder Araujo, Nicholas Piggin, Parth Y Shah, Paul Mackerras, Paul Menzel, Ram Pai, Randy Dunlap, Rashmica Gupta, Reza Arbab, Rodrigo R. Galvao, Russell Currey, Sam Bobroff, Scott Wood, Shilpasri G Bhat, Simon Guo, Souptick Joarder, Stan Johnson, Thiago Jung Bauermann, Tyrel Datwyler, Vaibhav Jain, Vasant Hegde, Venkat Rao, zhong jiang" * tag 'powerpc-4.19-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (234 commits) powerpc/mm/book3s/radix: Add mapping statistics powerpc/uaccess: Enable get_user(u64, *p) on 32-bit powerpc/mm/hash: Remove unnecessary do { } while(0) loop powerpc/64s: move machine check SLB flushing to mm/slb.c powerpc/powernv/idle: Fix build error powerpc/mm/tlbflush: update the mmu_gather page size while iterating address range powerpc/mm: remove warning about ‘type’ being set powerpc/32: Include setup.h header file to fix warnings powerpc: Move `path` variable inside DEBUG_PROM powerpc/powermac: Make some functions static powerpc/powermac: Remove variable x that's never read cxl: remove a dead branch powerpc/powermac: Add missing include of header pmac.h powerpc/kexec: Use common error handling code in setup_new_fdt() powerpc/xmon: Add address lookup for percpu symbols powerpc/mm: remove huge_pte_offset_and_shift() prototype powerpc/lib: Use patch_site to patch copy_32 functions once cache is enabled powerpc/pseries: Fix endianness while restoring of r3 in MCE handler. powerpc/fadump: merge adjacent memory ranges to reduce PT_LOAD segements powerpc/fadump: handle crash memory ranges array index overflow ...
2018-08-10cxl: remove a dead branchMathieu Malaterre1-5/+0
In commit 14baf4d9c739 ("cxl: Add guest-specific code") the following code was added: if (afu->crs_len < 0) { dev_err(&afu->dev, "Unexpected configuration record size value\n"); return -EINVAL; } However the variable `crs_len` is of type u64 and cannot be compared < 0. Remove the dead code section. Fix the following warning treated as error with W=1: ../drivers/misc/cxl/guest.c:919:19: error: comparison of unsigned expression < 0 is always false [-Werror=type-limits] Signed-off-by: Mathieu Malaterre <malat@debian.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-08-08misc: cxl: changed asterisk positionParth Y Shah1-1/+1
Resolved <"foo* bar" should be "foo *bar"> error Signed-off-by: Parth Y Shah <sparth1292@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-07-19cxl: Fix wrong comparison in cxl_adapter_context_get()Vaibhav Jain1-1/+1
Function atomic_inc_unless_negative() returns a bool to indicate success/failure. However cxl_adapter_context_get() wrongly compares the return value against '>=0' which will always be true. The patch fixes this comparison to '==0' there by also fixing this compile time warning: drivers/misc/cxl/main.c:290 cxl_adapter_context_get() warn: 'atomic_inc_unless_negative(&adapter->contexts_num)' is unsigned Fixes: 70b565bbdb91 ("cxl: Prevent adapter reset if an active context exists") Cc: stable@vger.kernel.org # v4.9+ Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Vaibhav Jain <vaibhav@linux.ibm.com> Acked-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>
2018-07-19Merge branch 'topic/ppc-kvm' into nextMichael Ellerman3-37/+16
Merge in some commits we're sharing with the KVM tree. I manually propagated the change from commit d3d4ffaae439 ("powerpc/powernv/ioda2: Reduce upper limit for DMA window size") into pci-ioda-tce.c. Conflicts: arch/powerpc/include/asm/cputable.h arch/powerpc/platforms/powernv/pci-ioda.c arch/powerpc/platforms/powernv/pci.h
2018-07-16powerpc/64s: Remove POWER9 DD1 supportNicholas Piggin3-37/+16
POWER9 DD1 was never a product. It is no longer supported by upstream firmware, and it is not effectively supported in Linux due to lack of testing. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Reviewed-by: Michael Ellerman <mpe@ellerman.id.au> [mpe: Remove arch_make_huge_pte() entirely] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-07-12cxl_getfile(): switch to alloc_file_pseudo()Al Viro1-17/+4
Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2018-07-12alloc_file(): switch to passing O_... flags instead of FMODE_... modeAl Viro1-2/+1
... so that it could set both ->f_flags and ->f_mode, without callers having to set ->f_flags manually. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2018-07-10cxl_getfile(): fix double-iput() on alloc_file() failuresAl Viro1-4/+4
Doing iput() after path_put() is wrong. Cc: stable@vger.kernel.org Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2018-07-02cxl: Remove abandonned capi support for the Mellanox CX4, final cleanupFrederic Barrat4-87/+7
Remove a few XSL/CX4 oddities which are no longer needed. A simple revert of the initial commits was not possible (or not worth it) due to the history of the code. Signed-off-by: Frederic Barrat <fbarrat@linux.ibm.com> Acked-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-07-02Revert "cxl: Allow a default context to be associated with an external pci_dev"Frederic Barrat6-91/+28
Remove abandonned capi support for the Mellanox CX4. This reverts commit a19bd79e31769626d288cc016e21a31b6f47bf6f. Signed-off-by: Frederic Barrat <fbarrat@linux.ibm.com> Acked-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-07-02Revert "cxl: Add cxl_slot_is_supported API"Frederic Barrat1-37/+0
Remove abandonned capi support for the Mellanox CX4. This reverts commit 4e56f858bdde5cbfb70f61baddfaa56a8ed851bf. Signed-off-by: Frederic Barrat <fbarrat@linux.ibm.com> Acked-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-07-02Revert "cxl: Add support for using the kernel API with a real PHB"Alastair D'Silva2-17/+2
Remove abandonned capi support for the Mellanox CX4. This reverts commit 317f5ef1b363417b6f1e93b90dfd2ffd6be6e867. Signed-off-by: Alastair D'Silva <alastair@d-silva.org> Acked-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-07-02Revert "cxl: Add cxl_check_and_switch_mode() API to switch bi-modal cards"Alastair D'Silva2-226/+18
Remove abandonned capi support for the Mellanox CX4. This reverts commit b0b5e5918ad1babfd1d43d98c7281926a7b57b9f. Signed-off-by: Alastair D'Silva <alastair@d-silva.org> Acked-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-07-02Revert "cxl: Add kernel APIs to get & set the max irqs per context"Alastair D'Silva1-27/+0
Remove abandonned capi support for the Mellanox CX4. This reverts commit 79384e4b71240abf50c375eea56060b0d79c242a. Signed-off-by: Alastair D'Silva <alastair@d-silva.org> Acked-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-07-02Revert "cxl: Add preliminary workaround for CX4 interrupt limitation"Alastair D'Silva5-44/+0
Remove abandonned capi support for the Mellanox CX4. This reverts commit cbce0917e2e47d4bf5aa3b5fd6b1247f33e1a126. Signed-off-by: Alastair D'Silva <alastair@d-silva.org> Acked-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-07-02Revert "cxl: Add support for interrupts on the Mellanox CX4"Alastair D'Silva4-108/+0
Remove abandonned capi support for the Mellanox CX4. This reverts commit a2f67d5ee8d950caaa7a6144cf0bfb256500b73e. Signed-off-by: Alastair D'Silva <alastair@d-silva.org> Acked-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-07-02Revert "cxl: Add kernel API to allow a context to operate with relocate ↵Alastair D'Silva4-24/+2
disabled" Remove abandonned capi support for the Mellanox CX4. The symbol 'cxl_set_translation_mode' is never called, so ctx->real_mode is always false. This reverts commit 7a0d85d313c2066712e530e668bc02bb741a685c. Signed-off-by: Alastair D'Silva <alastair@d-silva.org> Acked-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-06-12treewide: kzalloc() -> kcalloc()Kees Cook2-2/+2
The kzalloc() function has a 2-factor argument form, kcalloc(). This patch replaces cases of: kzalloc(a * b, gfp) with: kcalloc(a * b, gfp) as well as handling cases of: kzalloc(a * b * c, gfp) with: kzalloc(array3_size(a, b, c), gfp) as it's slightly less ugly than: kzalloc_array(array_size(a, b), c, gfp) This does, however, attempt to ignore constant size factors like: kzalloc(4 * 1024, gfp) though any constants defined via macros get caught up in the conversion. Any factors with a sizeof() of "unsigned char", "char", and "u8" were dropped, since they're redundant. The Coccinelle script used for this was: // Fix redundant parens around sizeof(). @@ type TYPE; expression THING, E; @@ ( kzalloc( - (sizeof(TYPE)) * E + sizeof(TYPE) * E , ...) | kzalloc( - (sizeof(THING)) * E + sizeof(THING) * E , ...) ) // Drop single-byte sizes and redundant parens. @@ expression COUNT; typedef u8; typedef __u8; @@ ( kzalloc( - sizeof(u8) * (COUNT) + COUNT , ...) | kzalloc( - sizeof(__u8) * (COUNT) + COUNT , ...) | kzalloc( - sizeof(char) * (COUNT) + COUNT , ...) | kzalloc( - sizeof(unsigned char) * (COUNT) + COUNT , ...) | kzalloc( - sizeof(u8) * COUNT + COUNT , ...) | kzalloc( - sizeof(__u8) * COUNT + COUNT , ...) | kzalloc( - sizeof(char) * COUNT + COUNT , ...) | kzalloc( - sizeof(unsigned char) * COUNT + COUNT , ...) ) // 2-factor product with sizeof(type/expression) and identifier or constant. @@ type TYPE; expression THING; identifier COUNT_ID; constant COUNT_CONST; @@ ( - kzalloc + kcalloc ( - sizeof(TYPE) * (COUNT_ID) + COUNT_ID, sizeof(TYPE) , ...) | - kzalloc + kcalloc ( - sizeof(TYPE) * COUNT_ID + COUNT_ID, sizeof(TYPE) , ...) | - kzalloc + kcalloc ( - sizeof(TYPE) * (COUNT_CONST) + COUNT_CONST, sizeof(TYPE) , ...) | - kzalloc + kcalloc ( - sizeof(TYPE) * COUNT_CONST + COUNT_CONST, sizeof(TYPE) , ...) | - kzalloc + kcalloc ( - sizeof(THING) * (COUNT_ID) + COUNT_ID, sizeof(THING) , ...) | - kzalloc + kcalloc ( - sizeof(THING) * COUNT_ID + COUNT_ID, sizeof(THING) , ...) | - kzalloc + kcalloc ( - sizeof(THING) * (COUNT_CONST) + COUNT_CONST, sizeof(THING) , ...) | - kzalloc + kcalloc ( - sizeof(THING) * COUNT_CONST + COUNT_CONST, sizeof(THING) , ...) ) // 2-factor product, only identifiers. @@ identifier SIZE, COUNT; @@ - kzalloc + kcalloc ( - SIZE * COUNT + COUNT, SIZE , ...) // 3-factor product with 1 sizeof(type) or sizeof(expression), with // redundant parens removed. @@ expression THING; identifier STRIDE, COUNT; type TYPE; @@ ( kzalloc( - sizeof(TYPE) * (COUNT) * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kzalloc( - sizeof(TYPE) * (COUNT) * STRIDE + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kzalloc( - sizeof(TYPE) * COUNT * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kzalloc( - sizeof(TYPE) * COUNT * STRIDE + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kzalloc( - sizeof(THING) * (COUNT) * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kzalloc( - sizeof(THING) * (COUNT) * STRIDE + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kzalloc( - sizeof(THING) * COUNT * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kzalloc( - sizeof(THING) * COUNT * STRIDE + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) ) // 3-factor product with 2 sizeof(variable), with redundant parens removed. @@ expression THING1, THING2; identifier COUNT; type TYPE1, TYPE2; @@ ( kzalloc( - sizeof(TYPE1) * sizeof(TYPE2) * COUNT + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2)) , ...) | kzalloc( - sizeof(TYPE1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2)) , ...) | kzalloc( - sizeof(THING1) * sizeof(THING2) * COUNT + array3_size(COUNT, sizeof(THING1), sizeof(THING2)) , ...) | kzalloc( - sizeof(THING1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(THING1), sizeof(THING2)) , ...) | kzalloc( - sizeof(TYPE1) * sizeof(THING2) * COUNT + array3_size(COUNT, sizeof(TYPE1), sizeof(THING2)) , ...) | kzalloc( - sizeof(TYPE1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(TYPE1), sizeof(THING2)) , ...) ) // 3-factor product, only identifiers, with redundant parens removed. @@ identifier STRIDE, SIZE, COUNT; @@ ( kzalloc( - (COUNT) * STRIDE * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - COUNT * (STRIDE) * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - COUNT * STRIDE * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - (COUNT) * (STRIDE) * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - COUNT * (STRIDE) * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - (COUNT) * STRIDE * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - (COUNT) * (STRIDE) * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - COUNT * STRIDE * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) ) // Any remaining multi-factor products, first at least 3-factor products, // when they're not all constants... @@ expression E1, E2, E3; constant C1, C2, C3; @@ ( kzalloc(C1 * C2 * C3, ...) | kzalloc( - (E1) * E2 * E3 + array3_size(E1, E2, E3) , ...) | kzalloc( - (E1) * (E2) * E3 + array3_size(E1, E2, E3) , ...) | kzalloc( - (E1) * (E2) * (E3) + array3_size(E1, E2, E3) , ...) | kzalloc( - E1 * E2 * E3 + array3_size(E1, E2, E3) , ...) ) // And then all remaining 2 factors products when they're not all constants, // keeping sizeof() as the second factor argument. @@ expression THING, E1, E2; type TYPE; constant C1, C2, C3; @@ ( kzalloc(sizeof(THING) * C2, ...) | kzalloc(sizeof(TYPE) * C2, ...) | kzalloc(C1 * C2 * C3, ...) | kzalloc(C1 * C2, ...) | - kzalloc + kcalloc ( - sizeof(TYPE) * (E2) + E2, sizeof(TYPE) , ...) | - kzalloc + kcalloc ( - sizeof(TYPE) * E2 + E2, sizeof(TYPE) , ...) | - kzalloc + kcalloc ( - sizeof(THING) * (E2) + E2, sizeof(THING) , ...) | - kzalloc + kcalloc ( - sizeof(THING) * E2 + E2, sizeof(THING) , ...) | - kzalloc + kcalloc ( - (E1) * E2 + E1, E2 , ...) | - kzalloc + kcalloc ( - (E1) * (E2) + E1, E2 , ...) | - kzalloc + kcalloc ( - E1 * E2 + E1, E2 , ...) ) Signed-off-by: Kees Cook <keescook@chromium.org>
2018-06-07Merge tag 'powerpc-4.18-1' of ↵Linus Torvalds2-6/+14
git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc updates from Michael Ellerman: "Notable changes: - Support for split PMD page table lock on 64-bit Book3S (Power8/9). - Add support for HAVE_RELIABLE_STACKTRACE, so we properly support live patching again. - Add support for patching barrier_nospec in copy_from_user() and syscall entry. - A couple of fixes for our data breakpoints on Book3S. - A series from Nick optimising TLB/mm handling with the Radix MMU. - Numerous small cleanups to squash sparse/gcc warnings from Mathieu Malaterre. - Several series optimising various parts of the 32-bit code from Christophe Leroy. - Removal of support for two old machines, "SBC834xE" and "C2K" ("GEFanuc,C2K"), which is why the diffstat has so many deletions. And many other small improvements & fixes. There's a few out-of-area changes. Some minor ftrace changes OK'ed by Steve, and a fix to our powernv cpuidle driver. Then there's a series touching mm, x86 and fs/proc/task_mmu.c, which cleans up some details around pkey support. It was ack'ed/reviewed by Ingo & Dave and has been in next for several weeks. Thanks to: Akshay Adiga, Alastair D'Silva, Alexey Kardashevskiy, Al Viro, Andrew Donnellan, Aneesh Kumar K.V, Anju T Sudhakar, Arnd Bergmann, Balbir Singh, Cédric Le Goater, Christophe Leroy, Christophe Lombard, Colin Ian King, Dave Hansen, Fabio Estevam, Finn Thain, Frederic Barrat, Gautham R. Shenoy, Haren Myneni, Hari Bathini, Ingo Molnar, Jonathan Neuschäfer, Josh Poimboeuf, Kamalesh Babulal, Madhavan Srinivasan, Mahesh Salgaonkar, Mark Greer, Mathieu Malaterre, Matthew Wilcox, Michael Neuling, Michal Suchanek, Naveen N. Rao, Nicholas Piggin, Nicolai Stange, Olof Johansson, Paul Gortmaker, Paul Mackerras, Peter Rosin, Pridhiviraj Paidipeddi, Ram Pai, Rashmica Gupta, Ravi Bangoria, Russell Currey, Sam Bobroff, Samuel Mendoza-Jonas, Segher Boessenkool, Shilpasri G Bhat, Simon Guo, Souptick Joarder, Stewart Smith, Thiago Jung Bauermann, Torsten Duwe, Vaibhav Jain, Wei Yongjun, Wolfram Sang, Yisheng Xie, YueHaibing" * tag 'powerpc-4.18-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (251 commits) powerpc/64s/radix: Fix missing ptesync in flush_cache_vmap cpuidle: powernv: Fix promotion from snooze if next state disabled powerpc: fix build failure by disabling attribute-alias warning in pci_32 ocxl: Fix missing unlock on error in afu_ioctl_enable_p9_wait() powerpc-opal: fix spelling mistake "Uniterrupted" -> "Uninterrupted" powerpc: fix spelling mistake: "Usupported" -> "Unsupported" powerpc/pkeys: Detach execute_only key on !PROT_EXEC powerpc/powernv: copy/paste - Mask SO bit in CR powerpc: Remove core support for Marvell mv64x60 hostbridges powerpc/boot: Remove core support for Marvell mv64x60 hostbridges powerpc/boot: Remove support for Marvell mv64x60 i2c controller powerpc/boot: Remove support for Marvell MPSC serial controller powerpc/embedded6xx: Remove C2K board support powerpc/lib: optimise PPC32 memcmp powerpc/lib: optimise 32 bits __clear_user() powerpc/time: inline arch_vtime_task_switch() powerpc/Makefile: set -mcpu=860 flag for the 8xx powerpc: Implement csum_ipv6_magic in assembly powerpc/32: Optimise __csum_partial() powerpc/lib: Adjust .balign inside string functions for PPC32 ...
2018-06-05Merge tag 'char-misc-4.18-rc1' of ↵Linus Torvalds1-3/+4
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc Pull char/misc driver updates from Greg KH: "Here is the "big" char and misc driver patches for 4.18-rc1. It's not a lot of stuff here, but there are some highlights: - coreboot driver updates - soundwire driver updates - android binder updates - fpga big sync, mostly documentation - lots of minor driver updates All of these have been in linux-next for a while with no reported issues" * tag 'char-misc-4.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (81 commits) vmw_balloon: fixing double free when batching mode is off MAINTAINERS: Add driver-api/fpga path fpga: clarify that unregister functions also free documentation: fpga: move fpga-region.txt to driver-api documentation: fpga: add bridge document to driver-api documentation: fpga: move fpga-mgr.txt to driver-api Documentation: fpga: move fpga overview to driver-api fpga: region: kernel-doc fixes fpga: bridge: kernel-doc fixes fpga: mgr: kernel-doc fixes fpga: use SPDX fpga: region: change api, add fpga_region_create/free fpga: bridge: change api, don't use drvdata fpga: manager: change api, don't use drvdata fpga: region: don't use drvdata in common fpga code Drivers: hv: vmbus: Removed an unnecessary cast from void * ver_linux: Drop redundant calls to system() to test if file is readable ver_linux: Move stderr redirection from function parameter to function body misc: IBM Virtual Management Channel Driver (VMC) rpmsg: Correct support for MODULE_DEVICE_TABLE() ...
2018-06-03Merge branch 'fixes' into nextMichael Ellerman3-0/+23
We ended up with an ugly conflict between fixes and next in ftrace.h involving multiple nested ifdefs, and the automatic resolution is wrong. So merge fixes into next so we can fix it up.
2018-06-02cxl: Configure PSL to not use APC virtual machinesVaibhav Jain1-2/+2
APC virtual machines arent used on POWER-9 chips and are already disabled in on-chip CAPP. They also need to be disabled on the PSL via 'PSL Data Send Control Register' by setting bit(47). This forces the PSL to send commands to CAPP with queue.id == 0. Fixes: 5632874311db ("cxl: Add support for POWER9 DD2") Cc: stable@vger.kernel.org # v4.15+ Signed-off-by: Vaibhav Jain <vaibhav@linux.vnet.ibm.com> Acked-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Reviewed-by: Alastair D'Silva <alastair@d-silva.org> Reviewed-by: Christophe Lombard <clombard@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-06-02cxl: Disable prefault_mode in Radix modeVaibhav Jain1-4/+12
Currently we see a kernel-oops reported on Power-9 while attaching a context to an AFU, with radix-mode and sysfs attr 'prefault_mode' set to anything other than 'none'. The backtrace of the oops is of this form: Unable to handle kernel paging request for data at address 0x00000080 Faulting instruction address: 0xc00800000bcf3b20 cpu 0x1: Vector: 300 (Data Access) at [c00000037f003800] pc: c00800000bcf3b20: cxl_load_segment+0x178/0x290 [cxl] lr: c00800000bcf39f0: cxl_load_segment+0x48/0x290 [cxl] sp: c00000037f003a80 msr: 9000000000009033 dar: 80 dsisr: 40000000 current = 0xc00000037f280000 paca = 0xc0000003ffffe600 softe: 3 irq_happened: 0x01 pid = 3529, comm = afp_no_int <snip> cxl_prefault+0xfc/0x248 [cxl] process_element_entry_psl9+0xd8/0x1a0 [cxl] cxl_attach_dedicated_process_psl9+0x44/0x130 [cxl] native_attach_process+0xc0/0x130 [cxl] afu_ioctl+0x3f4/0x5e0 [cxl] do_vfs_ioctl+0xdc/0x890 ksys_ioctl+0x68/0xf0 sys_ioctl+0x40/0xa0 system_call+0x58/0x6c The issue is caused as on Power-8 the AFU attr 'prefault_mode' was used to improve initial storage fault performance by prefaulting process segments. However on Power-9 with radix mode we don't have Storage-Segments that we can prefault. Also prefaulting process Pages will be too costly and fine-grained. Hence, since the prefaulting mechanism doesn't makes sense of radix-mode, this patch updates prefault_mode_store() to not allow any other value apart from CXL_PREFAULT_NONE when radix mode is enabled. Fixes: f24be42aab37 ("cxl: Add psl9 specific code") Cc: stable@vger.kernel.org # v4.12+ Signed-off-by: Vaibhav Jain <vaibhav@linux.ibm.com> Acked-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com> Acked-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-05-15cxl: Report the tunneled operations statusPhilippe Bergheaud3-1/+17
Failure to synchronize the tunneled operations does not prevent the initialization of the cxl card. This patch reports the tunneled operations status via /sys. Signed-off-by: Philippe Bergheaud <felix@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-05-15cxl: Set the PBCQ Tunnel BAR register when enabling capi modePhilippe Bergheaud1-0/+7
Skiboot used to set the default Tunnel BAR register value when capi mode was enabled. This approach was ok for the cxl driver, but prevented other drivers from choosing different values. Skiboot versions > 5.11 will not set the default value any longer. This patch modifies the cxl driver to set/reset the Tunnel BAR register when entering/exiting the cxl mode, with pnv_pci_set_tunnel_bar(). That should work with old skiboot (since we are re-writing the value already set) and new skiboot. mpe: The tunnel support was only merged into Linux recently, in commit d6a90bb83b50 ("powerpc/powernv: Enable tunneled operations") (v4.17-rc1), so with new skiboot kernels between that commit and this will not work correctly. Fixes: d6a90bb83b50 ("powerpc/powernv: Enable tunneled operations") Signed-off-by: Philippe Bergheaud <felix@linux.ibm.com> Reviewed-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>
2018-04-23misc: cxl: Change return type to vm_fault_tSouptick Joarder1-3/+4
Use new return type vm_fault_t for fault handler. For now, this is just documenting that the function returns a VM_FAULT value rather than an errno. Once all instances are converted, vm_fault_t will become a distinct type. Reference id -> 1c8f422059ae ("mm: change return type to vm_fault_t") previously cxl_mmap_fault returns VM_FAULT_NOPAGE as default value irrespective of vm_insert_pfn() return value. This bug is fixed with new vmf_insert_pfn() which will return VM_FAULT_ type based on err. Signed-off-by: Souptick Joarder <jrdr.linux@gmail.com> Acked-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-04-04cxl: Fix possible deadlock when processing page faults from cxllibFrederic Barrat1-30/+55
cxllib_handle_fault() is called by an external driver when it needs to have the host resolve page faults for a buffer. The buffer can cover several pages and VMAs. The function iterates over all the pages used by the buffer, based on the page size of the VMA. To ensure some stability while processing the faults, the thread T1 grabs the mm->mmap_sem semaphore with read access (R1). However, when processing a page fault for a single page, one of the underlying functions, copro_handle_mm_fault(), also grabs the same semaphore with read access (R2). So the thread T1 takes the semaphore twice. If another thread T2 tries to access the semaphore in write mode W1 (say, because it wants to allocate memory and calls 'brk'), then that thread T2 will have to wait because there's a reader (R1). If the thread T1 is processing a new page at that time, it won't get an automatic grant at R2, because there's now a writer thread waiting (T2). And we have a deadlock. The timeline is: 1. thread T1 owns the semaphore with read access R1 2. thread T2 requests write access W1 and waits 3. thread T1 requests read access R2 and waits The fix is for the thread T1 to release the semaphore R1 once it got the information it needs from the current VMA. The address space/VMAs could evolve while T1 iterates over the full buffer, but in the unlikely case where T1 misses a page, the external driver will raise a new page fault when retrying the memory access. Fixes: 3ced8d730063 ("cxl: Export library to support IBM XSL") Cc: stable@vger.kernel.org # 4.13+ Signed-off-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-14cxl: Fix timebase synchronization status on P9Christophe Lombard2-17/+12
The PSL Timebase register is updated by the PSL to maintain the timebase. On P9, the Timebase value is only provided by the CAPP as received the last time a timebase request was performed. The timebase requests are initiated through the adapter configuration or application registers. The specific sysfs entry "/sys/class/cxl/cardxx/psl_timebase_synced" is now dynamically updated according the content of the PSL Timebase register. Fixes: f24be42aab37 ("cxl: Add psl9 specific code") Signed-off-by: Christophe Lombard <clombard@linux.vnet.ibm.com> Reviewed-by: Vaibhav Jain <vaibhav@linux.vnet.ibm.com> Acked-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>