Commit 6bf625a4 authored by Michael Kelley's avatar Michael Kelley Committed by Wei Liu
Browse files

Drivers: hv: vmbus: Rework use of DMA_BIT_MASK(64) 



Using DMA_BIT_MASK(64) as an initializer for a global variable
causes problems with Clang 12.0.1. The compiler doesn't understand
that value 64 is excluded from the shift at compile time, resulting
in a build error.

While this is a compiler problem, avoid the issue by setting up
the dma_mask memory as part of struct hv_device, and initialize
it using dma_set_mask().

Reported-by: default avatarNathan Chancellor <nathan@kernel.org>
Reported-by: default avatarVitaly Chikunov <vt@altlinux.org>
Reported-by: default avatarJakub Kicinski <kuba@kernel.org>
Fixes: 743b237c ("scsi: storvsc: Add Isolation VM support for storvsc driver")
Signed-off-by: default avatarMichael Kelley <mikelley@microsoft.com>
Reviewed-by: default avatarNathan Chancellor <nathan@kernel.org>
Tested-by: default avatarNathan Chancellor <nathan@kernel.org>
Link: https://lore.kernel.org/r/1644176216-12531-1-git-send-email-mikelley@microsoft.com


Signed-off-by: default avatarWei Liu <wei.liu@kernel.org>
parent 8bc69f86

drivers/hv/vmbus_drv.c

+2 −2
Original line number Diff line number Diff line
@@ -2082,7 +2082,6 @@ struct hv_device *vmbus_device_create(const guid_t *type, 
	return child_device_obj;

}



static u64 vmbus_dma_mask = DMA_BIT_MASK(64);

/*

 * vmbus_device_register - Register the child device

 */
@@ -2123,8 +2122,9 @@ int vmbus_device_register(struct hv_device *child_device_obj) 
	}

	hv_debug_add_dev_dir(child_device_obj);



	child_device_obj->device.dma_mask = &vmbus_dma_mask;

	child_device_obj->device.dma_parms = &child_device_obj->dma_parms;

	child_device_obj->device.dma_mask = &child_device_obj->dma_mask;

	dma_set_mask(&child_device_obj->device, DMA_BIT_MASK(64));

	return 0;



err_kset_unregister:

include/linux/hyperv.h

+1 −0
Original line number Diff line number Diff line
@@ -1262,6 +1262,7 @@ struct hv_device { 
	struct vmbus_channel *channel;

	struct kset	     *channels_kset;

	struct device_dma_parameters dma_parms;

	u64 dma_mask;



	/* place holder to keep track of the dir for hv device in debugfs */

	struct dentry *debug_dir;