linux-toradex.git/drivers/hv, branch v4.19 Linux kernel for Apalis and Colibri modules Drivers: hv: vmbus: Use get/put_cpu() in vmbus_connect() 2018-09-30T15:49:55+00:00 Dexuan Cui decui@microsoft.com 2018-09-17T04:14:54+00:00 41e270f6898e7502be9fd6920ee0a108ca259d36 With CONFIG_DEBUG_PREEMPT=y, I always see this warning: BUG: using smp_processor_id() in preemptible [00000000] Fix the false warning by using get/put_cpu(). Here vmbus_connect() sends a message to the host and waits for the host's response. The host will deliver the response message and an interrupt on CPU msg->target_vcpu, and later the interrupt handler will wake up vmbus_connect(). vmbus_connect() doesn't really have to run on the same cpu as CPU msg->target_vcpu, so it's safe to call put_cpu() just here. Signed-off-by: Dexuan Cui <decui@microsoft.com> Cc: stable@vger.kernel.org Cc: K. Y. Srinivasan <kys@microsoft.com> Cc: Haiyang Zhang <haiyangz@microsoft.com> Cc: Stephen Hemminger <sthemmin@microsoft.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
With CONFIG_DEBUG_PREEMPT=y, I always see this warning:
BUG: using smp_processor_id() in preemptible [00000000]

Fix the false warning by using get/put_cpu().

Here vmbus_connect() sends a message to the host and waits for the
host's response. The host will deliver the response message and an
interrupt on CPU msg->target_vcpu, and later the interrupt handler
will wake up vmbus_connect(). vmbus_connect() doesn't really have
to run on the same cpu as CPU msg->target_vcpu, so it's safe to
call put_cpu() just here.

Signed-off-by: Dexuan Cui <decui@microsoft.com>
Cc: stable@vger.kernel.org
Cc: K. Y. Srinivasan <kys@microsoft.com>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
vmbus: don't return values for uninitalized channels 2018-09-12T07:31:00+00:00 Stephen Hemminger stephen@networkplumber.org 2018-08-20T21:16:40+00:00 6712cc9c22117a8af9f3df272b4a44fd2e4201cd For unsupported device types, the vmbus channel ringbuffer is never initialized, and therefore reading the sysfs files will return garbage or cause a kernel OOPS. Fixes: c2e5df616e1a ("vmbus: add per-channel sysfs info") Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Cc: <stable@vger.kernel.org> # 4.15 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
For unsupported device types, the vmbus channel ringbuffer is never
initialized, and therefore reading the sysfs files will return garbage
or cause a kernel OOPS.

Fixes: c2e5df616e1a ("vmbus: add per-channel sysfs info")

Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Cc: <stable@vger.kernel.org> # 4.15
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Drivers: hv: vmbus: Cleanup synic memory free path 2018-08-02T08:20:59+00:00 Michael Kelley mikelley@microsoft.com 2018-08-02T03:08:25+00:00 572086325ce9a9e348b8748e830653f3959e88b6 clk_evt memory is not being freed when the synic is shutdown or when there is an allocation error. Add the appropriate kfree() call, along with a comment to clarify how the memory gets freed after an allocation error. Make the free path consistent by removing checks for NULL since kfree() and free_page() already do the check. Signed-off-by: Michael Kelley <mikelley@microsoft.com> Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
clk_evt memory is not being freed when the synic is shutdown
or when there is an allocation error.  Add the appropriate
kfree() call, along with a comment to clarify how the memory
gets freed after an allocation error.  Make the free path
consistent by removing checks for NULL since kfree() and
free_page() already do the check.

Signed-off-by: Michael Kelley <mikelley@microsoft.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Drivers: hv: vmbus: Remove use of slow_virt_to_phys() 2018-08-02T08:20:59+00:00 Michael Kelley mikelley@microsoft.com 2018-08-02T03:08:24+00:00 6ba34171bcbd10321c6cf554e0c1144d170f9d1a slow_virt_to_phys() is only implemented for arch/x86. Remove its use in arch independent Hyper-V drivers, and replace with test for vmalloc() address followed by appropriate v-to-p function. This follows the typical pattern of other drivers and avoids the need to implement slow_virt_to_phys() for Hyper-V on ARM64. Signed-off-by: Michael Kelley <mikelley@microsoft.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
slow_virt_to_phys() is only implemented for arch/x86.
Remove its use in arch independent Hyper-V drivers, and
replace with test for vmalloc() address followed by
appropriate v-to-p function. This follows the typical
pattern of other drivers and avoids the need to implement
slow_virt_to_phys() for Hyper-V on ARM64.

Signed-off-by: Michael Kelley <mikelley@microsoft.com>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Drivers: hv: vmbus: Reset the channel callback in vmbus_onoffer_rescind() 2018-08-02T08:20:59+00:00 Dexuan Cui decui@microsoft.com 2018-08-02T03:08:23+00:00 d3b26dd7cb0e3433bfd3c1d4dcf74c6039bb49fb Before setting channel->rescind in vmbus_rescind_cleanup(), we should make sure the channel callback won't run any more, otherwise a high-level driver like pci_hyperv, which may be infinitely waiting for the host VSP's response and notices the channel has been rescinded, can't safely give up: e.g., in hv_pci_protocol_negotiation() -> wait_for_response(), it's unsafe to exit from wait_for_response() and proceed with the on-stack variable "comp_pkt" popped. The issue was originally spotted by Michael Kelley <mikelley@microsoft.com>. In vmbus_close_internal(), the patch also minimizes the range protected by disabling/enabling channel->callback_event: we don't really need that for the whole function. Signed-off-by: Dexuan Cui <decui@microsoft.com> Reviewed-by: Michael Kelley <mikelley@microsoft.com> Cc: stable@vger.kernel.org Cc: K. Y. Srinivasan <kys@microsoft.com> Cc: Stephen Hemminger <sthemmin@microsoft.com> Cc: Michael Kelley <mikelley@microsoft.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
Before setting channel->rescind in vmbus_rescind_cleanup(), we should make
sure the channel callback won't run any more, otherwise a high-level
driver like pci_hyperv, which may be infinitely waiting for the host VSP's
response and notices the channel has been rescinded, can't safely give
up: e.g., in hv_pci_protocol_negotiation() -> wait_for_response(), it's
unsafe to exit from wait_for_response() and proceed with the on-stack
variable "comp_pkt" popped. The issue was originally spotted by
Michael Kelley <mikelley@microsoft.com>.

In vmbus_close_internal(), the patch also minimizes the range protected by
disabling/enabling channel->callback_event: we don't really need that for
the whole function.

Signed-off-by: Dexuan Cui <decui@microsoft.com>
Reviewed-by: Michael Kelley <mikelley@microsoft.com>
Cc: stable@vger.kernel.org
Cc: K. Y. Srinivasan <kys@microsoft.com>
Cc: Stephen Hemminger <sthemmin@microsoft.com>
Cc: Michael Kelley <mikelley@microsoft.com>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Drivers: hv: vmbus: add numa_node to sysfs 2018-07-29T06:09:56+00:00 Stephen Hemminger stephen@networkplumber.org 2018-07-28T21:58:48+00:00 7ceb1c37533e2298797188087796dd44931d86af Being able to find the numa_node for a device is useful for userspace drivers (DPDK) and also for diagnosing performance issues. This makes vmbus similar to pci. Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
Being able to find the numa_node for a device is useful for userspace
drivers (DPDK) and also for diagnosing performance issues.  This makes
vmbus similar to pci.

Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Drivers: hv: vmbus: Get rid of MSR access from vmbus_drv.c 2018-07-29T06:09:56+00:00 Sunil Muthuswamy sunilmut@microsoft.com 2018-07-28T21:58:47+00:00 9d9c9656871cd9fc1d03a2b4f47a278d54c6d03d Get rid of ISA specific code from vmus_drv.c which is common code. Fixes: 81b18bce48af ("Drivers: HV: Send one page worth of kmsg dump over Hyper-V during panic") Signed-off-by: Sunil Muthuswamy <sunilmut@microsoft.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
Get rid of ISA specific code from vmus_drv.c which is common code.

Fixes: 81b18bce48af ("Drivers: HV: Send one page worth of kmsg dump over Hyper-V during panic")

Signed-off-by: Sunil Muthuswamy <sunilmut@microsoft.com>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Drivers: hv: vmbus: Fix the issue with freeing up hv_ctl_table_hdr 2018-07-29T06:09:56+00:00 Sunil Muthuswamy sunilmut@microsoft.com 2018-07-28T21:58:46+00:00 8afc06dd75c06b9d6e70e4a72fdafbd4cab8d1df The check to free the Hyper-V control table header was reversed. This fixes it. Fixes: 81b18bce48af ("Drivers: HV: Send one page worth of kmsg dump over Hyper-V during panic") Signed-off-by: Sunil Muthuswamy <sunilmut@microsoft.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
The check to free the Hyper-V control table header was reversed. This
fixes it.

Fixes: 81b18bce48af ("Drivers: HV: Send one page worth of kmsg dump over Hyper-V during panic")

Signed-off-by: Sunil Muthuswamy <sunilmut@microsoft.com>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Drivers: hv: vmus: Fix the check for return value from kmsg get dump buffer 2018-07-29T06:09:56+00:00 Sunil Muthuswamy sunilmut@microsoft.com 2018-07-28T21:58:45+00:00 ddcaf3ca4c3c87b955ad6f57952250030be77791 The code to support panic control message was checking the return was checking the return value from kmsg_dump_get_buffer as error value, which is not what the routine returns. This fixes it. Fixes: 81b18bce48af ("Drivers: HV: Send one page worth of kmsg dump over Hyper-V during panic") Signed-off-by: Sunil Muthuswamy <sunilmut@microsoft.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
The code to support panic control message was checking the return was
checking the return value from kmsg_dump_get_buffer as error value, which
is not what the routine returns. This fixes it.

Fixes: 81b18bce48af ("Drivers: HV: Send one page worth of kmsg dump over Hyper-V during panic")

Signed-off-by: Sunil Muthuswamy <sunilmut@microsoft.com>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Drivers: HV: Send one page worth of kmsg dump over Hyper-V during panic 2018-07-08T13:54:31+00:00 Sunil Muthuswamy sunilmut@microsoft.com 2018-07-08T02:56:51+00:00 81b18bce48af3e222ca9eebb3b931f59141b7b49 In the VM mode on Hyper-V, currently, when the kernel panics, an error code and few register values are populated in an MSR and the Hypervisor notified. This information is collected on the host. The amount of information currently collected is found to be limited and not very actionable. To gather more actionable data, such as stack trace, the proposal is to write one page worth of kmsg data on an allocated page and the Hypervisor notified of the page address through the MSR. - Sysctl option to control the behavior, with ON by default. Cc: K. Y. Srinivasan <kys@microsoft.com> Cc: Stephen Hemminger <sthemmin@microsoft.com> Signed-off-by: Sunil Muthuswamy <sunilmut@microsoft.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
In the VM mode on Hyper-V, currently, when the kernel panics, an error
code and few register values are populated in an MSR and the Hypervisor
notified. This information is collected on the host. The amount of
information currently collected is found to be limited and not very
actionable. To gather more actionable data, such as stack trace, the
proposal is to write one page worth of kmsg data on an allocated page
and the Hypervisor notified of the page address through the MSR.

- Sysctl option to control the behavior, with ON by default.

Cc: K. Y. Srinivasan <kys@microsoft.com>
Cc: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: Sunil Muthuswamy <sunilmut@microsoft.com>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>