linux-toradex.git/drivers/misc/cxl, branch v4.4.73

cxl: Fix error path on bad ioctl

2017-06-14T11:16:24+00:00

commit cec422c11caeeccae709e9942058b6b644ce434c upstream.

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")
Signed-off-by: Frederic Barrat 
Reviewed-by: Vaibhav Jain 
Reviewed-by: Andrew Donnellan 
Signed-off-by: Michael Ellerman 
Signed-off-by: Greg Kroah-Hartman

cxl: Enable PCI device ID for future IBM CXL adapter

2016-09-15T06:27:41+00:00

[ Upstream commit 68adb7bfd66504e97364651fb7dac3f9c8aa8561 ]

Add support for future IBM Coherent Accelerator (CXL) device
with ID of 0x0601.

Signed-off-by: Uma Krishnan 
Reviewed-by: Matthew R. Ochs 
Signed-off-by: Michael Ellerman 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

cxl: fix build for GCC 4.6.x

2016-09-15T06:27:41+00:00

[ Upstream commit aa09545589ceeff884421d8eb38d04963190afbe ]

GCC 4.6.3 does not support -Wno-unused-const-variable. Instead, use the
kbuild infrastructure that checks if this options exists.

Fixes: 2cd55c68c0a4 ("cxl: Fix build failure due to -Wunused-variable behaviour change")
Suggested-by: Michal Marek 
Suggested-by: Arnd Bergmann 
Signed-off-by: Brian Norris 
Signed-off-by: Michael Ellerman 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

cxl: Fix DSI misses when the context owning task exits

2016-09-15T06:27:41+00:00

[ Upstream commit 7b8ad495d59280b634a7b546f4cdf58cf4d65f61 ]

Presently when a user-space process issues CXL_IOCTL_START_WORK ioctl we
store the pid of the current task_struct and use it to get pointer to
the mm_struct of the process, while processing page or segment faults
from the capi card. However this causes issues when the thread that had
originally issued the start-work ioctl exits in which case the stored
pid is no more valid and the cxl driver is unable to handle faults as
the mm_struct corresponding to process is no more accessible.

This patch fixes this issue by using the mm_struct of the next alive
task in the thread group. This is done by iterating over all the tasks
in the thread group starting from thread group leader and calling
get_task_mm on each one of them. When a valid mm_struct is obtained the
pid of the associated task is stored in the context replacing the
exiting one for handling future faults.

The patch introduces a new function named get_mem_context that checks if
the current task pointed to by ctx->pid is dead? If yes it performs the
steps described above. Also a new variable cxl_context.glpid is
introduced which stores the pid of the thread group leader associated
with the context owning task.

Reported-by: Matthew R. Ochs 
Reported-by: Frank Haverkamp 
Suggested-by: Ian Munsie 
Signed-off-by: Vaibhav Jain 
Acked-by: Ian Munsie 
Reviewed-by: Frederic Barrat 
Reviewed-by: Matthew R. Ochs 
Signed-off-by: Michael Ellerman 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

cxl: Fix possible idr warning when contexts are released

2016-09-15T06:27:41+00:00

[ Upstream commit 1b5df59e50874b9034c0fa389cd52b65f1f93292 ]

An idr warning is reported when a context is release after the capi card
is unbound from the cxl driver via sysfs. Below are the steps to
reproduce:

1. Create multiple afu contexts in an user-space application using libcxl.
2. Unbind capi card from cxl using command of form
   echo  > /sys/bus/pci/drivers/cxl-pci/unbind
3. Exit/kill the application owning afu contexts.

After above steps a warning message is usually seen in the kernel logs
of the form "idr_remove called for id= which is not
allocated."

This is caused by the function cxl_release_afu which destroys the
contexts_idr table. So when a context is release no entry for context pe
is found in the contexts_idr table and idr code prints this warning.

This patch fixes this issue by increasing & decreasing the ref-count on
the afu device when a context is initialized or when its freed
respectively. This prevents the afu from being released until all the
afu contexts have been released. The patch introduces two new functions
namely cxl_afu_get/put that manage the ref-count on the afu device.

Also the patch removes code inside cxl_dev_context_init that increases ref
on the afu device as its guaranteed to be alive during this function.

Reported-by: Ian Munsie 
Signed-off-by: Vaibhav Jain 
Acked-by: Ian Munsie 
Signed-off-by: Michael Ellerman 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

cxl: Keep IRQ mappings on context teardown

2016-05-04T21:48:48+00:00

commit d6776bba44d9752f6cdf640046070e71ee4bba7b upstream.

Keep IRQ mappings on context teardown.  This won't leak IRQs as if we
allocate the mapping again, the generic code will give the same
mapping used last time.

Doing this works around a race in the generic code. Masking the
interrupt introduces a race which can crash the kernel or result in
IRQ that is never EOIed. The lost of EOI results in all subsequent
mappings to the same HW IRQ never receiving an interrupt.

We've seen this race with cxl test cases which are doing heavy context
startup and teardown at the same time as heavy interrupt load.

A fix to the generic code is being investigated also.

Signed-off-by: Michael Neuling 
Tested-by: Andrew Donnellan 
Acked-by: Ian Munsie 
Tested-by: Vaibhav Jain 
Signed-off-by: Michael Ellerman 
Signed-off-by: Greg Kroah-Hartman

cxl: Fix PSL timebase synchronization detection

2016-03-09T23:34:55+00:00

commit 923adb1646d5ba739d2a1e63ee20d60574d9da8e upstream.

The PSL timebase synchronization is seemingly failing for
configuration not including VIRT_CPU_ACCOUNTING_NATIVE. The driver
shows the following trace in dmesg:
PSL: Timebase sync: giving up!

The PSL timebase register is actually syncing correctly, but the cxl
driver is not detecting it. Fix is to use the proper timebase-to-time
conversion.

Signed-off-by: Frederic Barrat 
Acked-by: Michael Neuling 
Reviewed-by: Matthew R. Ochs 
Acked-by: Ian Munsie 
Reviewed-by: Andrew Donnellan 
Reviewed-by: Vaibhav Jain 
Signed-off-by: Michael Ellerman 
Signed-off-by: Greg Kroah-Hartman

cxl: use correct operator when writing pcie config space values

2016-03-03T23:07:17+00:00

commit 48f0f6b717e314a30be121b67e1d044f6d311d66 upstream.

When writing a value to config space, cxl_pcie_write_config() calls
cxl_pcie_config_info() to obtain a mask and shift value, shifts the new
value accordingly, then uses the mask to combine the shifted value with the
existing value at the address as part of a read-modify-write pattern.

Currently, we use a logical OR operator rather than a bitwise OR operator,
which means any use of this function results in an incorrect value being
written. Replace the logical OR operator with a bitwise OR operator so the
value is written correctly.

Reported-by: Michael Ellerman 
Fixes: 6f7f0b3df6d4 ("cxl: Add AFU virtual PHB and kernel API")
Signed-off-by: Andrew Donnellan 
Acked-by: Ian Munsie 
Signed-off-by: Michael Ellerman 
Signed-off-by: Greg Kroah-Hartman

cxl: Set endianess of kernel contexts

2015-12-08T05:57:01+00:00

A process element (defined in CAIA) keeps track of the endianess of
contexts through the Little Endian (LE) bit of the State Register. It
is currently set for user contexts, but was somehow forgotten for
kernel contexts, so this patch fixes it.
It could lead to erratic behavior from an AFU when the context is
attached through the kernel API.

Fixes: 2f663527bd6a ("cxl: Configure PSL for kernel contexts and merge code")
Cc: stable@vger.kernel.org # 4.2+
Signed-off-by: Frederic Barrat 
Suggested-by: Michael Neuling 
Signed-off-by: Michael Ellerman

Merge tag 'powerpc-4.4-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

2015-11-06T07:38:43+00:00

Pull powerpc updates from Michael Ellerman:

 - Kconfig: remove BE-only platforms from LE kernel build from Boqun
   Feng
 - Refresh ps3_defconfig from Geoff Levand
 - Emit GNU & SysV hashes for the vdso from Michael Ellerman
 - Define an enum for the bolted SLB indexes from Anshuman Khandual
 - Use a local to avoid multiple calls to get_slb_shadow() from Michael
   Ellerman
 - Add gettimeofday() benchmark from Michael Neuling
 - Avoid link stack corruption in __get_datapage() from Michael Neuling
 - Add virt_to_pfn and use this instead of opencoding from Aneesh Kumar
   K.V
 - Add ppc64le_defconfig from Michael Ellerman
 - pseries: extract of_helpers module from Andy Shevchenko
 - Correct string length in pseries_of_derive_parent() from Nathan
   Fontenot
 - Free the MSI bitmap if it was slab allocated from Denis Kirjanov
 - Shorten irq_chip name for the SIU from Christophe Leroy
 - Wait 1s for secondaries to enter OPAL during kexec from Samuel
   Mendoza-Jonas
 - Fix _ALIGN_* errors due to type difference, from Aneesh Kumar K.V
 - powerpc/pseries/hvcserver: don't memset pi_buff if it is null from
   Colin Ian King
 - Disable hugepd for 64K page size, from Aneesh Kumar K.V
 - Differentiate between hugetlb and THP during page walk from Aneesh
   Kumar K.V
 - Make PCI non-optional for pseries from Michael Ellerman
 - Individual System V IPC system calls from Sam bobroff
 - Add selftest of unmuxed IPC calls from Michael Ellerman
 - discard .exit.data at runtime from Stephen Rothwell
 - Delete old orphaned PrPMC 280/2800 DTS and boot file, from Paul
   Gortmaker
 - Use of_get_next_parent to simplify code from Christophe Jaillet
 - Paginate some xmon output from Sam bobroff
 - Add some more elements to the xmon PACA dump from Michael Ellerman
 - Allow the tm-syscall selftest to build with old headers from Michael
   Ellerman
 - Run EBB selftests only on POWER8 from Denis Kirjanov
 - Drop CONFIG_TUNE_CELL in favour of CONFIG_CELL_CPU from Michael
   Ellerman
 - Avoid reference to potentially freed memory in prom.c from Christophe
   Jaillet
 - Quieten boot wrapper output with run_cmd from Geoff Levand
 - EEH fixes and cleanups from Gavin Shan
 - Fix recursive fenced PHB on Broadcom shiner adapter from Gavin Shan
 - Use of_get_next_parent() in of_get_ibm_chip_id() from Michael
   Ellerman
 - Fix section mismatch warning in msi_bitmap_alloc() from Denis
   Kirjanov
 - Fix ps3-lpm white space from Rudhresh Kumar J
 - Fix ps3-vuart null dereference from Colin King
 - nvram: Add missing kfree in error path from Christophe Jaillet
 - nvram: Fix function name in some errors messages, from Christophe
   Jaillet
 - drivers/macintosh: adb: fix misleading Kconfig help text from Aaro
   Koskinen
 - agp/uninorth: fix a memleak in create_gatt_table from Denis Kirjanov
 - cxl: Free virtual PHB when removing from Andrew Donnellan
 - scripts/kconfig/Makefile: Allow KBUILD_DEFCONFIG to be a target from
   Michael Ellerman
 - scripts/kconfig/Makefile: Fix KBUILD_DEFCONFIG check when building
   with O= from Michael Ellerman
 - Freescale updates from Scott: Highlights include 64-bit book3e
   kexec/kdump support, a rework of the qoriq clock driver, device tree
   changes including qoriq fman nodes, support for a new 85xx board, and
   some fixes.
 - MPC5xxx updates from Anatolij: Highlights include a driver for
   MPC512x LocalPlus Bus FIFO with its device tree binding
   documentation, mpc512x device tree updates and some minor fixes.

* tag 'powerpc-4.4-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (106 commits)
  powerpc/msi: Fix section mismatch warning in msi_bitmap_alloc()
  powerpc/prom: Use of_get_next_parent() in of_get_ibm_chip_id()
  powerpc/pseries: Correct string length in pseries_of_derive_parent()
  powerpc/e6500: hw tablewalk: make sure we invalidate and write to the same tlb entry
  powerpc/mpc85xx: Add FSL QorIQ DPAA FMan support to the SoC device tree(s)
  powerpc/mpc85xx: Create dts components for the FSL QorIQ DPAA FMan
  powerpc/fsl: Add #clock-cells and clockgen label to clockgen nodes
  powerpc: handle error case in cpm_muram_alloc()
  powerpc: mpic: use IRQCHIP_SKIP_SET_WAKE instead of redundant mpic_irq_set_wake
  powerpc/book3e-64: Enable kexec
  powerpc/book3e-64/kexec: Set "r4 = 0" when entering spinloop
  powerpc/booke: Only use VIRT_PHYS_OFFSET on booke32
  powerpc/book3e-64/kexec: Enable SMP release
  powerpc/book3e-64/kexec: create an identity TLB mapping
  powerpc/book3e-64: Don't limit paca to 256 MiB
  powerpc/book3e/kdump: Enable crash_kexec_wait_realmode
  powerpc/book3e: support CONFIG_RELOCATABLE
  powerpc/booke64: Fix args to copy_and_flush
  powerpc/book3e-64: rename interrupt_end_book3e with __end_interrupts
  powerpc/e6500: kexec: Handle hardware threads
  ...