diff mbox series

drm/vmwgfx: Use dma-coherent memory for high-bandwidth port messaging

Message ID 20191113095144.2981-1-thomas_os@shipmail.org (mailing list archive)
State New, archived
Headers show
Series drm/vmwgfx: Use dma-coherent memory for high-bandwidth port messaging | expand

Commit Message

Thomas Hellström (Intel) Nov. 13, 2019, 9:51 a.m. UTC
From: Thomas Hellstrom <thellstrom@vmware.com>

With AMD-SEV high-bandwidth port messaging runs into trouble since the
message content is encrypted using the vm-specific key, and the
hypervisor is unable to read it.

So use unencrypted dma-coherent bounce buffers for temporary message
storage space. Allocating that memory is expensive so a future
optimization might include a static unencrypted memory area for messages.

Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Brian Paul <brianp@vmware.com>
---
 drivers/gpu/drm/vmwgfx/vmwgfx_drv.c |  4 +--
 drivers/gpu/drm/vmwgfx/vmwgfx_drv.h |  4 +--
 drivers/gpu/drm/vmwgfx/vmwgfx_msg.c | 45 +++++++++++++++++------------
 3 files changed, 31 insertions(+), 22 deletions(-)

Comments

Nathan Chancellor Nov. 13, 2019, 8:01 p.m. UTC | #1
On Wed, Nov 13, 2019 at 10:51:42AM +0100, Thomas Hellström (VMware) wrote:
> From: Thomas Hellstrom <thellstrom@vmware.com>
> 
> With AMD-SEV high-bandwidth port messaging runs into trouble since the
> message content is encrypted using the vm-specific key, and the
> hypervisor is unable to read it.
> 
> So use unencrypted dma-coherent bounce buffers for temporary message
> storage space. Allocating that memory is expensive so a future
> optimization might include a static unencrypted memory area for messages.
> 
> Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
> Reviewed-by: Brian Paul <brianp@vmware.com>

Hi Thomas,

The 0day team has been doing clang builds for us and sending the results
to our mailing list for triage; this patch causes the following warning.
Seems legitimate, mind taking a look at it and resolving it how you see
fit?

Cheers,
Nathan

On Thu, Nov 14, 2019 at 03:36:44AM +0800, kbuild test robot wrote:
> CC: kbuild-all@lists.01.org
> In-Reply-To: <20191113095144.2981-1-thomas_os@shipmail.org>
> References: <20191113095144.2981-1-thomas_os@shipmail.org>
> TO: "Thomas Hellström (VMware)" <thomas_os@shipmail.org>
> CC: dri-devel@lists.freedesktop.org, Thomas Hellstrom <thellstrom@vmware.com>, Brian Paul <brianp@vmware.com>, Thomas Hellstrom <thellstrom@vmware.com>, Brian Paul <brianp@vmware.com>
> CC: Thomas Hellstrom <thellstrom@vmware.com>, Brian Paul <brianp@vmware.com>
> 
> Hi "Thomas,
> 
> I love your patch! Perhaps something to improve:
> 
> [auto build test WARNING on linus/master]
> [also build test WARNING on v5.4-rc7 next-20191113]
> [if your patch is applied to the wrong git tree, please drop us a note to help
> improve the system. BTW, we also suggest to use '--base' option to specify the
> base tree in git format-patch, please see https://stackoverflow.com/a/37406982]
> 
> url:    https://github.com/0day-ci/linux/commits/Thomas-Hellstr-m-VMware/drm-vmwgfx-Use-dma-coherent-memory-for-high-bandwidth-port-messaging/20191114-020818
> base:   https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git 0e3f1ad80fc8cb0c517fd9a9afb22752b741fa76
> config: x86_64-rhel-7.6 (attached as .config)
> compiler: clang version 10.0.0 (git://gitmirror/llvm_project 335ac2eb662ce5f1888e2a50310b01fba2d40d68)
> reproduce:
>         # save the attached .config to linux build tree
>         make ARCH=x86_64 
> 
> If you fix the issue, kindly add following tag
> Reported-by: kbuild test robot <lkp@intel.com>
> 
> All warnings (new ones prefixed by >>):
> 
> >> drivers/gpu/drm/vmwgfx/vmwgfx_msg.c:441:6: warning: variable 'reply_handle' is used uninitialized whenever '||' condition is true [-Wsometimes-uninitialized]
>            if (vmw_send_msg(&channel, msg) ||
>                ^~~~~~~~~~~~~~~~~~~~~~~~~~~
>    drivers/gpu/drm/vmwgfx/vmwgfx_msg.c:467:47: note: uninitialized use occurs here
>            dma_free_coherent(dev, reply_len + 1, reply, reply_handle);
>                                                         ^~~~~~~~~~~~
>    drivers/gpu/drm/vmwgfx/vmwgfx_msg.c:441:6: note: remove the '||' if its condition is always false
>            if (vmw_send_msg(&channel, msg) ||
>                ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>    drivers/gpu/drm/vmwgfx/vmwgfx_msg.c:421:37: note: initialize the variable 'reply_handle' to silence this warning
>            dma_addr_t req_handle, reply_handle;
>                                               ^
>                                                = 0
>    1 warning generated.
> 
> vim +441 drivers/gpu/drm/vmwgfx/vmwgfx_msg.c
> 
> 89da76fde68de1 Sinclair Yeh      2016-04-27  400  
> 89da76fde68de1 Sinclair Yeh      2016-04-27  401  
> 89da76fde68de1 Sinclair Yeh      2016-04-27  402  /**
> 89da76fde68de1 Sinclair Yeh      2016-04-27  403   * vmw_host_get_guestinfo: Gets a GuestInfo parameter
> 89da76fde68de1 Sinclair Yeh      2016-04-27  404   *
> 89da76fde68de1 Sinclair Yeh      2016-04-27  405   * Gets the value of a  GuestInfo.* parameter.  The value returned will be in
> 89da76fde68de1 Sinclair Yeh      2016-04-27  406   * a string, and it is up to the caller to post-process.
> 89da76fde68de1 Sinclair Yeh      2016-04-27  407   *
> 6bdb21230a2a01 Thomas Hellstrom  2019-11-13  408   * @dev: Pointer to struct device used for coherent memory allocation
> 89da76fde68de1 Sinclair Yeh      2016-04-27  409   * @guest_info_param:  Parameter to get, e.g. GuestInfo.svga.gl3
> 89da76fde68de1 Sinclair Yeh      2016-04-27  410   * @buffer: if NULL, *reply_len will contain reply size.
> 89da76fde68de1 Sinclair Yeh      2016-04-27  411   * @length: size of the reply_buf.  Set to size of reply upon return
> 89da76fde68de1 Sinclair Yeh      2016-04-27  412   *
> 89da76fde68de1 Sinclair Yeh      2016-04-27  413   * Returns: 0 on success
> 89da76fde68de1 Sinclair Yeh      2016-04-27  414   */
> 6bdb21230a2a01 Thomas Hellstrom  2019-11-13  415  int vmw_host_get_guestinfo(struct device *dev, const char *guest_info_param,
> 89da76fde68de1 Sinclair Yeh      2016-04-27  416  			   char *buffer, size_t *length)
> 89da76fde68de1 Sinclair Yeh      2016-04-27  417  {
> 89da76fde68de1 Sinclair Yeh      2016-04-27  418  	struct rpc_channel channel;
> 89da76fde68de1 Sinclair Yeh      2016-04-27  419  	char *msg, *reply = NULL;
> 6073a09210e06f Himanshu Jha      2018-03-22  420  	size_t reply_len = 0;
> 6bdb21230a2a01 Thomas Hellstrom  2019-11-13  421  	dma_addr_t req_handle, reply_handle;
> 6bdb21230a2a01 Thomas Hellstrom  2019-11-13  422  	int req_len = strlen("info-get ") + strlen(guest_info_param) + 1;
> 89da76fde68de1 Sinclair Yeh      2016-04-27  423  
> 89da76fde68de1 Sinclair Yeh      2016-04-27  424  	if (!vmw_msg_enabled)
> 89da76fde68de1 Sinclair Yeh      2016-04-27  425  		return -ENODEV;
> 89da76fde68de1 Sinclair Yeh      2016-04-27  426  
> 89da76fde68de1 Sinclair Yeh      2016-04-27  427  	if (!guest_info_param || !length)
> 89da76fde68de1 Sinclair Yeh      2016-04-27  428  		return -EINVAL;
> 89da76fde68de1 Sinclair Yeh      2016-04-27  429  
> 6bdb21230a2a01 Thomas Hellstrom  2019-11-13  430  	msg = dma_alloc_coherent(dev, req_len, &req_handle, GFP_KERNEL);
> 1a4adb05632e90 Ravikant B Sharma 2016-11-08  431  	if (!msg) {
> 3fbeccf8ceb165 Thomas Hellstrom  2018-06-20  432  		DRM_ERROR("Cannot allocate memory to get guest info \"%s\".",
> 3fbeccf8ceb165 Thomas Hellstrom  2018-06-20  433  			  guest_info_param);
> 89da76fde68de1 Sinclair Yeh      2016-04-27  434  		return -ENOMEM;
> 89da76fde68de1 Sinclair Yeh      2016-04-27  435  	}
> 6bdb21230a2a01 Thomas Hellstrom  2019-11-13  436  	snprintf(msg, req_len, "info-get %s", guest_info_param);
> 89da76fde68de1 Sinclair Yeh      2016-04-27  437  
> f37230c0ad4810 Thomas Hellstrom  2018-05-23  438  	if (vmw_open_channel(&channel, RPCI_PROTOCOL_NUM))
> f37230c0ad4810 Thomas Hellstrom  2018-05-23  439  		goto out_open;
> 89da76fde68de1 Sinclair Yeh      2016-04-27  440  
> f37230c0ad4810 Thomas Hellstrom  2018-05-23 @441  	if (vmw_send_msg(&channel, msg) ||
> 6bdb21230a2a01 Thomas Hellstrom  2019-11-13  442  	    vmw_recv_msg(dev, &channel, (void *) &reply, &reply_len,
> 6bdb21230a2a01 Thomas Hellstrom  2019-11-13  443  			 &reply_handle))
> f37230c0ad4810 Thomas Hellstrom  2018-05-23  444  		goto out_msg;
> 89da76fde68de1 Sinclair Yeh      2016-04-27  445  
> f37230c0ad4810 Thomas Hellstrom  2018-05-23  446  	vmw_close_channel(&channel);
> 89da76fde68de1 Sinclair Yeh      2016-04-27  447  	if (buffer && reply && reply_len > 0) {
> 89da76fde68de1 Sinclair Yeh      2016-04-27  448  		/* Remove reply code, which are the first 2 characters of
> 89da76fde68de1 Sinclair Yeh      2016-04-27  449  		 * the reply
> 89da76fde68de1 Sinclair Yeh      2016-04-27  450  		 */
> 89da76fde68de1 Sinclair Yeh      2016-04-27  451  		reply_len = max(reply_len - 2, (size_t) 0);
> 89da76fde68de1 Sinclair Yeh      2016-04-27  452  		reply_len = min(reply_len, *length);
> 89da76fde68de1 Sinclair Yeh      2016-04-27  453  
> 89da76fde68de1 Sinclair Yeh      2016-04-27  454  		if (reply_len > 0)
> 89da76fde68de1 Sinclair Yeh      2016-04-27  455  			memcpy(buffer, reply + 2, reply_len);
> 89da76fde68de1 Sinclair Yeh      2016-04-27  456  	}
> 89da76fde68de1 Sinclair Yeh      2016-04-27  457  
> 89da76fde68de1 Sinclair Yeh      2016-04-27  458  	*length = reply_len;
> 89da76fde68de1 Sinclair Yeh      2016-04-27  459  
> 6bdb21230a2a01 Thomas Hellstrom  2019-11-13  460  	dma_free_coherent(dev, reply_len + 1, reply, reply_handle);
> 6bdb21230a2a01 Thomas Hellstrom  2019-11-13  461  	dma_free_coherent(dev, req_len, msg, req_handle);
> 89da76fde68de1 Sinclair Yeh      2016-04-27  462  
> f37230c0ad4810 Thomas Hellstrom  2018-05-23  463  	return 0;
> f37230c0ad4810 Thomas Hellstrom  2018-05-23  464  
> f37230c0ad4810 Thomas Hellstrom  2018-05-23  465  out_msg:
> f37230c0ad4810 Thomas Hellstrom  2018-05-23  466  	vmw_close_channel(&channel);
> 6bdb21230a2a01 Thomas Hellstrom  2019-11-13  467  	dma_free_coherent(dev, reply_len + 1, reply, reply_handle);
> f37230c0ad4810 Thomas Hellstrom  2018-05-23  468  out_open:
> f37230c0ad4810 Thomas Hellstrom  2018-05-23  469  	*length = 0;
> f37230c0ad4810 Thomas Hellstrom  2018-05-23  470  
> 6bdb21230a2a01 Thomas Hellstrom  2019-11-13  471  	DRM_ERROR("Failed to get guest info \"%s\".", guest_info_param);
> 6bdb21230a2a01 Thomas Hellstrom  2019-11-13  472  	dma_free_coherent(dev, req_len, msg, req_handle);
> f37230c0ad4810 Thomas Hellstrom  2018-05-23  473  	return -EINVAL;
> 89da76fde68de1 Sinclair Yeh      2016-04-27  474  }
> 89da76fde68de1 Sinclair Yeh      2016-04-27  475  
> 
> :::::: The code at line 441 was first introduced by commit
> :::::: f37230c0ad481091bc136788ff8b37dc86300c6d drm/vmwgfx: Fix host logging / guestinfo reading error paths
> 
> :::::: TO: Thomas Hellstrom <thellstrom@vmware.com>
> :::::: CC: Thomas Hellstrom <thellstrom@vmware.com>
> 
> ---
> 0-DAY kernel test infrastructure                 Open Source Technology Center
> https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org Intel Corporation
Thomas Hellström (Intel) Nov. 13, 2019, 8:11 p.m. UTC | #2
Hi, Nathan,

On 11/13/19 9:01 PM, Nathan Chancellor wrote:
> On Wed, Nov 13, 2019 at 10:51:42AM +0100, Thomas Hellström (VMware) wrote:
>> From: Thomas Hellstrom <thellstrom@vmware.com>
>>
>> With AMD-SEV high-bandwidth port messaging runs into trouble since the
>> message content is encrypted using the vm-specific key, and the
>> hypervisor is unable to read it.
>>
>> So use unencrypted dma-coherent bounce buffers for temporary message
>> storage space. Allocating that memory is expensive so a future
>> optimization might include a static unencrypted memory area for messages.
>>
>> Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
>> Reviewed-by: Brian Paul <brianp@vmware.com>
> Hi Thomas,
>
> The 0day team has been doing clang builds for us and sending the results
> to our mailing list for triage; this patch causes the following warning.
> Seems legitimate, mind taking a look at it and resolving it how you see
> fit?
>
> Cheers,
> Nathan

This should be harmless as dma_free_coherent() with reply == NULL is a 
nop, but anyway I'll respin to silence the warning.

Thanks,

Thomas


> On Thu, Nov 14, 2019 at 03:36:44AM +0800, kbuild test robot wrote:
>> CC: kbuild-all@lists.01.org
>> In-Reply-To: <20191113095144.2981-1-thomas_os@shipmail.org>
>> References: <20191113095144.2981-1-thomas_os@shipmail.org>
>> TO: "Thomas Hellström (VMware)" <thomas_os@shipmail.org>
>> CC: dri-devel@lists.freedesktop.org, Thomas Hellstrom <thellstrom@vmware.com>, Brian Paul <brianp@vmware.com>, Thomas Hellstrom <thellstrom@vmware.com>, Brian Paul <brianp@vmware.com>
>> CC: Thomas Hellstrom <thellstrom@vmware.com>, Brian Paul <brianp@vmware.com>
>>
>> Hi "Thomas,
>>
>> I love your patch! Perhaps something to improve:
>>
>> [auto build test WARNING on linus/master]
>> [also build test WARNING on v5.4-rc7 next-20191113]
>> [if your patch is applied to the wrong git tree, please drop us a note to help
>> improve the system. BTW, we also suggest to use '--base' option to specify the
>> base tree in git format-patch, please see https://stackoverflow.com/a/37406982]
>>
>> url:    https://github.com/0day-ci/linux/commits/Thomas-Hellstr-m-VMware/drm-vmwgfx-Use-dma-coherent-memory-for-high-bandwidth-port-messaging/20191114-020818
>> base:   https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git 0e3f1ad80fc8cb0c517fd9a9afb22752b741fa76
>> config: x86_64-rhel-7.6 (attached as .config)
>> compiler: clang version 10.0.0 (git://gitmirror/llvm_project 335ac2eb662ce5f1888e2a50310b01fba2d40d68)
>> reproduce:
>>          # save the attached .config to linux build tree
>>          make ARCH=x86_64
>>
>> If you fix the issue, kindly add following tag
>> Reported-by: kbuild test robot <lkp@intel.com>
>>
>> All warnings (new ones prefixed by >>):
>>
>>>> drivers/gpu/drm/vmwgfx/vmwgfx_msg.c:441:6: warning: variable 'reply_handle' is used uninitialized whenever '||' condition is true [-Wsometimes-uninitialized]
>>             if (vmw_send_msg(&channel, msg) ||
>>                 ^~~~~~~~~~~~~~~~~~~~~~~~~~~
>>     drivers/gpu/drm/vmwgfx/vmwgfx_msg.c:467:47: note: uninitialized use occurs here
>>             dma_free_coherent(dev, reply_len + 1, reply, reply_handle);
>>                                                          ^~~~~~~~~~~~
>>     drivers/gpu/drm/vmwgfx/vmwgfx_msg.c:441:6: note: remove the '||' if its condition is always false
>>             if (vmw_send_msg(&channel, msg) ||
>>                 ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>>     drivers/gpu/drm/vmwgfx/vmwgfx_msg.c:421:37: note: initialize the variable 'reply_handle' to silence this warning
>>             dma_addr_t req_handle, reply_handle;
>>                                                ^
>>                                                 = 0
>>     1 warning generated.
>>
>> vim +441 drivers/gpu/drm/vmwgfx/vmwgfx_msg.c
>>
>> 89da76fde68de1 Sinclair Yeh      2016-04-27  400
>> 89da76fde68de1 Sinclair Yeh      2016-04-27  401
>> 89da76fde68de1 Sinclair Yeh      2016-04-27  402  /**
>> 89da76fde68de1 Sinclair Yeh      2016-04-27  403   * vmw_host_get_guestinfo: Gets a GuestInfo parameter
>> 89da76fde68de1 Sinclair Yeh      2016-04-27  404   *
>> 89da76fde68de1 Sinclair Yeh      2016-04-27  405   * Gets the value of a  GuestInfo.* parameter.  The value returned will be in
>> 89da76fde68de1 Sinclair Yeh      2016-04-27  406   * a string, and it is up to the caller to post-process.
>> 89da76fde68de1 Sinclair Yeh      2016-04-27  407   *
>> 6bdb21230a2a01 Thomas Hellstrom  2019-11-13  408   * @dev: Pointer to struct device used for coherent memory allocation
>> 89da76fde68de1 Sinclair Yeh      2016-04-27  409   * @guest_info_param:  Parameter to get, e.g. GuestInfo.svga.gl3
>> 89da76fde68de1 Sinclair Yeh      2016-04-27  410   * @buffer: if NULL, *reply_len will contain reply size.
>> 89da76fde68de1 Sinclair Yeh      2016-04-27  411   * @length: size of the reply_buf.  Set to size of reply upon return
>> 89da76fde68de1 Sinclair Yeh      2016-04-27  412   *
>> 89da76fde68de1 Sinclair Yeh      2016-04-27  413   * Returns: 0 on success
>> 89da76fde68de1 Sinclair Yeh      2016-04-27  414   */
>> 6bdb21230a2a01 Thomas Hellstrom  2019-11-13  415  int vmw_host_get_guestinfo(struct device *dev, const char *guest_info_param,
>> 89da76fde68de1 Sinclair Yeh      2016-04-27  416  			   char *buffer, size_t *length)
>> 89da76fde68de1 Sinclair Yeh      2016-04-27  417  {
>> 89da76fde68de1 Sinclair Yeh      2016-04-27  418  	struct rpc_channel channel;
>> 89da76fde68de1 Sinclair Yeh      2016-04-27  419  	char *msg, *reply = NULL;
>> 6073a09210e06f Himanshu Jha      2018-03-22  420  	size_t reply_len = 0;
>> 6bdb21230a2a01 Thomas Hellstrom  2019-11-13  421  	dma_addr_t req_handle, reply_handle;
>> 6bdb21230a2a01 Thomas Hellstrom  2019-11-13  422  	int req_len = strlen("info-get ") + strlen(guest_info_param) + 1;
>> 89da76fde68de1 Sinclair Yeh      2016-04-27  423
>> 89da76fde68de1 Sinclair Yeh      2016-04-27  424  	if (!vmw_msg_enabled)
>> 89da76fde68de1 Sinclair Yeh      2016-04-27  425  		return -ENODEV;
>> 89da76fde68de1 Sinclair Yeh      2016-04-27  426
>> 89da76fde68de1 Sinclair Yeh      2016-04-27  427  	if (!guest_info_param || !length)
>> 89da76fde68de1 Sinclair Yeh      2016-04-27  428  		return -EINVAL;
>> 89da76fde68de1 Sinclair Yeh      2016-04-27  429
>> 6bdb21230a2a01 Thomas Hellstrom  2019-11-13  430  	msg = dma_alloc_coherent(dev, req_len, &req_handle, GFP_KERNEL);
>> 1a4adb05632e90 Ravikant B Sharma 2016-11-08  431  	if (!msg) {
>> 3fbeccf8ceb165 Thomas Hellstrom  2018-06-20  432  		DRM_ERROR("Cannot allocate memory to get guest info \"%s\".",
>> 3fbeccf8ceb165 Thomas Hellstrom  2018-06-20  433  			  guest_info_param);
>> 89da76fde68de1 Sinclair Yeh      2016-04-27  434  		return -ENOMEM;
>> 89da76fde68de1 Sinclair Yeh      2016-04-27  435  	}
>> 6bdb21230a2a01 Thomas Hellstrom  2019-11-13  436  	snprintf(msg, req_len, "info-get %s", guest_info_param);
>> 89da76fde68de1 Sinclair Yeh      2016-04-27  437
>> f37230c0ad4810 Thomas Hellstrom  2018-05-23  438  	if (vmw_open_channel(&channel, RPCI_PROTOCOL_NUM))
>> f37230c0ad4810 Thomas Hellstrom  2018-05-23  439  		goto out_open;
>> 89da76fde68de1 Sinclair Yeh      2016-04-27  440
>> f37230c0ad4810 Thomas Hellstrom  2018-05-23 @441  	if (vmw_send_msg(&channel, msg) ||
>> 6bdb21230a2a01 Thomas Hellstrom  2019-11-13  442  	    vmw_recv_msg(dev, &channel, (void *) &reply, &reply_len,
>> 6bdb21230a2a01 Thomas Hellstrom  2019-11-13  443  			 &reply_handle))
>> f37230c0ad4810 Thomas Hellstrom  2018-05-23  444  		goto out_msg;
>> 89da76fde68de1 Sinclair Yeh      2016-04-27  445
>> f37230c0ad4810 Thomas Hellstrom  2018-05-23  446  	vmw_close_channel(&channel);
>> 89da76fde68de1 Sinclair Yeh      2016-04-27  447  	if (buffer && reply && reply_len > 0) {
>> 89da76fde68de1 Sinclair Yeh      2016-04-27  448  		/* Remove reply code, which are the first 2 characters of
>> 89da76fde68de1 Sinclair Yeh      2016-04-27  449  		 * the reply
>> 89da76fde68de1 Sinclair Yeh      2016-04-27  450  		 */
>> 89da76fde68de1 Sinclair Yeh      2016-04-27  451  		reply_len = max(reply_len - 2, (size_t) 0);
>> 89da76fde68de1 Sinclair Yeh      2016-04-27  452  		reply_len = min(reply_len, *length);
>> 89da76fde68de1 Sinclair Yeh      2016-04-27  453
>> 89da76fde68de1 Sinclair Yeh      2016-04-27  454  		if (reply_len > 0)
>> 89da76fde68de1 Sinclair Yeh      2016-04-27  455  			memcpy(buffer, reply + 2, reply_len);
>> 89da76fde68de1 Sinclair Yeh      2016-04-27  456  	}
>> 89da76fde68de1 Sinclair Yeh      2016-04-27  457
>> 89da76fde68de1 Sinclair Yeh      2016-04-27  458  	*length = reply_len;
>> 89da76fde68de1 Sinclair Yeh      2016-04-27  459
>> 6bdb21230a2a01 Thomas Hellstrom  2019-11-13  460  	dma_free_coherent(dev, reply_len + 1, reply, reply_handle);
>> 6bdb21230a2a01 Thomas Hellstrom  2019-11-13  461  	dma_free_coherent(dev, req_len, msg, req_handle);
>> 89da76fde68de1 Sinclair Yeh      2016-04-27  462
>> f37230c0ad4810 Thomas Hellstrom  2018-05-23  463  	return 0;
>> f37230c0ad4810 Thomas Hellstrom  2018-05-23  464
>> f37230c0ad4810 Thomas Hellstrom  2018-05-23  465  out_msg:
>> f37230c0ad4810 Thomas Hellstrom  2018-05-23  466  	vmw_close_channel(&channel);
>> 6bdb21230a2a01 Thomas Hellstrom  2019-11-13  467  	dma_free_coherent(dev, reply_len + 1, reply, reply_handle);
>> f37230c0ad4810 Thomas Hellstrom  2018-05-23  468  out_open:
>> f37230c0ad4810 Thomas Hellstrom  2018-05-23  469  	*length = 0;
>> f37230c0ad4810 Thomas Hellstrom  2018-05-23  470
>> 6bdb21230a2a01 Thomas Hellstrom  2019-11-13  471  	DRM_ERROR("Failed to get guest info \"%s\".", guest_info_param);
>> 6bdb21230a2a01 Thomas Hellstrom  2019-11-13  472  	dma_free_coherent(dev, req_len, msg, req_handle);
>> f37230c0ad4810 Thomas Hellstrom  2018-05-23  473  	return -EINVAL;
>> 89da76fde68de1 Sinclair Yeh      2016-04-27  474  }
>> 89da76fde68de1 Sinclair Yeh      2016-04-27  475
>>
>> :::::: The code at line 441 was first introduced by commit
>> :::::: f37230c0ad481091bc136788ff8b37dc86300c6d drm/vmwgfx: Fix host logging / guestinfo reading error paths
>>
>> :::::: TO: Thomas Hellstrom <thellstrom@vmware.com>
>> :::::: CC: Thomas Hellstrom <thellstrom@vmware.com>
>>
>> ---
>> 0-DAY kernel test infrastructure                 Open Source Technology Center
>> https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org Intel Corporation
diff mbox series

Patch

diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_drv.c b/drivers/gpu/drm/vmwgfx/vmwgfx_drv.c
index 81a95651643f..fc0283659c41 100644
--- a/drivers/gpu/drm/vmwgfx/vmwgfx_drv.c
+++ b/drivers/gpu/drm/vmwgfx/vmwgfx_drv.c
@@ -908,13 +908,13 @@  static int vmw_driver_load(struct drm_device *dev, unsigned long chipset)
 
 	snprintf(host_log, sizeof(host_log), "vmwgfx: %s-%s",
 		VMWGFX_REPO, VMWGFX_GIT_VERSION);
-	vmw_host_log(host_log);
+	vmw_host_log(dev->dev, host_log);
 
 	memset(host_log, 0, sizeof(host_log));
 	snprintf(host_log, sizeof(host_log), "vmwgfx: Module Version: %d.%d.%d",
 		VMWGFX_DRIVER_MAJOR, VMWGFX_DRIVER_MINOR,
 		VMWGFX_DRIVER_PATCHLEVEL);
-	vmw_host_log(host_log);
+	vmw_host_log(dev->dev, host_log);
 
 	if (dev_priv->enable_fb) {
 		vmw_fifo_resource_inc(dev_priv);
diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_drv.h b/drivers/gpu/drm/vmwgfx/vmwgfx_drv.h
index b18842f73081..a77bf72cb9ac 100644
--- a/drivers/gpu/drm/vmwgfx/vmwgfx_drv.h
+++ b/drivers/gpu/drm/vmwgfx/vmwgfx_drv.h
@@ -1389,9 +1389,9 @@  int vmw_bo_cpu_blit(struct ttm_buffer_object *dst,
 		    struct vmw_diff_cpy *diff);
 
 /* Host messaging -vmwgfx_msg.c: */
-int vmw_host_get_guestinfo(const char *guest_info_param,
+int vmw_host_get_guestinfo(struct device *dev, const char *guest_info_param,
 			   char *buffer, size_t *length);
-int vmw_host_log(const char *log);
+int vmw_host_log(struct device *dev, const char *log);
 
 /* VMW logging */
 
diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_msg.c b/drivers/gpu/drm/vmwgfx/vmwgfx_msg.c
index b6c5e4c2ac3c..f439b7afa3a5 100644
--- a/drivers/gpu/drm/vmwgfx/vmwgfx_msg.c
+++ b/drivers/gpu/drm/vmwgfx/vmwgfx_msg.c
@@ -304,8 +304,8 @@  STACK_FRAME_NON_STANDARD(vmw_send_msg);
  * @msg:  [OUT] message received from the host
  * @msg_len: message length
  */
-static int vmw_recv_msg(struct rpc_channel *channel, void **msg,
-			size_t *msg_len)
+static int vmw_recv_msg(struct device *dev, struct rpc_channel *channel,
+			void **msg, size_t *msg_len, dma_addr_t *dma_handle)
 {
 	unsigned long eax, ebx, ecx, edx, si, di;
 	char *reply;
@@ -339,7 +339,8 @@  static int vmw_recv_msg(struct rpc_channel *channel, void **msg,
 			return 0;
 
 		reply_len = ebx;
-		reply     = kzalloc(reply_len + 1, GFP_KERNEL);
+		reply = dma_alloc_coherent(dev, reply_len + 1, dma_handle,
+					   GFP_KERNEL);
 		if (!reply) {
 			DRM_ERROR("Cannot allocate memory for host message reply.\n");
 			return -ENOMEM;
@@ -350,7 +351,7 @@  static int vmw_recv_msg(struct rpc_channel *channel, void **msg,
 		ebx = vmw_port_hb_in(channel, reply, reply_len,
 				     !!(HIGH_WORD(ecx) & MESSAGE_STATUS_HB));
 		if ((HIGH_WORD(ebx) & MESSAGE_STATUS_SUCCESS) == 0) {
-			kfree(reply);
+			dma_free_coherent(dev, reply_len + 1, reply, *dma_handle);
 			reply = NULL;
 			if ((HIGH_WORD(ebx) & MESSAGE_STATUS_CPT) != 0) {
 				/* A checkpoint occurred. Retry. */
@@ -374,7 +375,7 @@  static int vmw_recv_msg(struct rpc_channel *channel, void **msg,
 			eax, ebx, ecx, edx, si, di);
 
 		if ((HIGH_WORD(ecx) & MESSAGE_STATUS_SUCCESS) == 0) {
-			kfree(reply);
+			dma_free_coherent(dev, reply_len + 1, reply, *dma_handle);
 			reply = NULL;
 			if ((HIGH_WORD(ecx) & MESSAGE_STATUS_CPT) != 0) {
 				/* A checkpoint occurred. Retry. */
@@ -404,18 +405,21 @@  STACK_FRAME_NON_STANDARD(vmw_recv_msg);
  * Gets the value of a  GuestInfo.* parameter.  The value returned will be in
  * a string, and it is up to the caller to post-process.
  *
+ * @dev: Pointer to struct device used for coherent memory allocation
  * @guest_info_param:  Parameter to get, e.g. GuestInfo.svga.gl3
  * @buffer: if NULL, *reply_len will contain reply size.
  * @length: size of the reply_buf.  Set to size of reply upon return
  *
  * Returns: 0 on success
  */
-int vmw_host_get_guestinfo(const char *guest_info_param,
+int vmw_host_get_guestinfo(struct device *dev, const char *guest_info_param,
 			   char *buffer, size_t *length)
 {
 	struct rpc_channel channel;
 	char *msg, *reply = NULL;
 	size_t reply_len = 0;
+	dma_addr_t req_handle, reply_handle;
+	int req_len = strlen("info-get ") + strlen(guest_info_param) + 1;
 
 	if (!vmw_msg_enabled)
 		return -ENODEV;
@@ -423,18 +427,20 @@  int vmw_host_get_guestinfo(const char *guest_info_param,
 	if (!guest_info_param || !length)
 		return -EINVAL;
 
-	msg = kasprintf(GFP_KERNEL, "info-get %s", guest_info_param);
+	msg = dma_alloc_coherent(dev, req_len, &req_handle, GFP_KERNEL);
 	if (!msg) {
 		DRM_ERROR("Cannot allocate memory to get guest info \"%s\".",
 			  guest_info_param);
 		return -ENOMEM;
 	}
+	snprintf(msg, req_len, "info-get %s", guest_info_param);
 
 	if (vmw_open_channel(&channel, RPCI_PROTOCOL_NUM))
 		goto out_open;
 
 	if (vmw_send_msg(&channel, msg) ||
-	    vmw_recv_msg(&channel, (void *) &reply, &reply_len))
+	    vmw_recv_msg(dev, &channel, (void *) &reply, &reply_len,
+			 &reply_handle))
 		goto out_msg;
 
 	vmw_close_channel(&channel);
@@ -451,19 +457,19 @@  int vmw_host_get_guestinfo(const char *guest_info_param,
 
 	*length = reply_len;
 
-	kfree(reply);
-	kfree(msg);
+	dma_free_coherent(dev, reply_len + 1, reply, reply_handle);
+	dma_free_coherent(dev, req_len, msg, req_handle);
 
 	return 0;
 
 out_msg:
 	vmw_close_channel(&channel);
-	kfree(reply);
+	dma_free_coherent(dev, reply_len + 1, reply, reply_handle);
 out_open:
 	*length = 0;
-	kfree(msg);
-	DRM_ERROR("Failed to get guest info \"%s\".", guest_info_param);
 
+	DRM_ERROR("Failed to get guest info \"%s\".", guest_info_param);
+	dma_free_coherent(dev, req_len, msg, req_handle);
 	return -EINVAL;
 }
 
@@ -472,16 +478,18 @@  int vmw_host_get_guestinfo(const char *guest_info_param,
 /**
  * vmw_host_log: Sends a log message to the host
  *
+ * @dev: Pointer to struct device used for coherent memory allocation
  * @log: NULL terminated string
  *
  * Returns: 0 on success
  */
-int vmw_host_log(const char *log)
+int vmw_host_log(struct device *dev, const char *log)
 {
 	struct rpc_channel channel;
 	char *msg;
 	int ret = 0;
-
+	dma_addr_t log_handle;
+	int log_len = strlen("log ") + strlen(log) + 1;
 
 	if (!vmw_msg_enabled)
 		return -ENODEV;
@@ -489,11 +497,12 @@  int vmw_host_log(const char *log)
 	if (!log)
 		return ret;
 
-	msg = kasprintf(GFP_KERNEL, "log %s", log);
+	msg = dma_alloc_coherent(dev, log_len, &log_handle, GFP_KERNEL);
 	if (!msg) {
 		DRM_ERROR("Cannot allocate memory for host log message.\n");
 		return -ENOMEM;
 	}
+	snprintf(msg, log_len, "log %s", log);
 
 	if (vmw_open_channel(&channel, RPCI_PROTOCOL_NUM))
 		goto out_open;
@@ -502,14 +511,14 @@  int vmw_host_log(const char *log)
 		goto out_msg;
 
 	vmw_close_channel(&channel);
-	kfree(msg);
+	dma_free_coherent(dev, log_len, msg, log_handle);
 
 	return 0;
 
 out_msg:
 	vmw_close_channel(&channel);
 out_open:
-	kfree(msg);
+	dma_free_coherent(dev, log_len, msg, log_handle);
 	DRM_ERROR("Failed to send host log message.\n");
 
 	return -EINVAL;