Re: drivers/misc/vmw_balloon.c:200: warning: Function parameter or member '5' not described in 'vmballoon_batch_entry'

From: Nadav Amit
Date: Mon Nov 06 2023 - 06:10:11 EST


[ -Xavier ]

> On Nov 6, 2023, at 8:18 AM, kernel test robot <yujie.liu@xxxxxxxxx> wrote:
>
> !! External Email
>
> tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
> head: 77fa2fbe87fc605c4bfa87dff87be9bfded0e9a3
> commit: 6c94875799eaf99bfdbb0efce21d75e1c56e96d5 vmw_balloon: simplifying batch access
> date: 5 years ago

Isn’t is slightly strange for the bot to check 5 year old patches?

> All warnings (new ones prefixed by >>):
>
> In file included from drivers/misc/vmw_balloon.c:28:
> include/linux/vmw_vmci_defs.h:159:33: warning: 'VMCI_ANON_SRC_HANDLE' defined but not used [-Wunused-const-variable=]
> 159 | static const struct vmci_handle VMCI_ANON_SRC_HANDLE = {
> | ^~~~~~~~~~~~~~~~~~~~
>>> drivers/misc/vmw_balloon.c:200: warning: Function parameter or member '5' not described in 'vmballoon_batch_entry'
> drivers/misc/vmw_balloon.o: warning: objtool: vmballoon_deflate()+0x1ca: sibling call from callable instruction with modified stack frame
> drivers/misc/vmw_balloon.o: warning: objtool: vmballoon_debug_show()+0x73: sibling call from callable instruction with modified stack frame
> drivers/misc/vmw_balloon.o: warning: objtool: vmballoon_inflate()+0xa1: sibling call from callable instruction with modified stack frame
> drivers/misc/vmw_balloon.o: warning: objtool: vmballoon_work()+0x84: sibling call from callable instruction with modified stack frame
>
>
> vim +200 drivers/misc/vmw_balloon.c
>
> 365bd7ef7ec8eb Philip P. Moltmann 2015-08-06 188
> 6c94875799eaf9 Nadav Amit 2018-09-20 189 /**
> 6c94875799eaf9 Nadav Amit 2018-09-20 190 * struct vmballoon_batch_entry - a batch entry for lock or unlock.
> 6c94875799eaf9 Nadav Amit 2018-09-20 191 *
> 6c94875799eaf9 Nadav Amit 2018-09-20 192 * @status: the status of the operation, which is written by the hypervisor.
> 6c94875799eaf9 Nadav Amit 2018-09-20 193 * @reserved: reserved for future use. Must be set to zero.
> 6c94875799eaf9 Nadav Amit 2018-09-20 194 * @pfn: the physical frame number of the page to be locked or unlocked.
> 6c94875799eaf9 Nadav Amit 2018-09-20 195 */
> 6c94875799eaf9 Nadav Amit 2018-09-20 196 struct vmballoon_batch_entry {
> 6c94875799eaf9 Nadav Amit 2018-09-20 197 u64 status : 5;
> 6c94875799eaf9 Nadav Amit 2018-09-20 198 u64 reserved : PAGE_SHIFT - 5;
> 6c94875799eaf9 Nadav Amit 2018-09-20 199 u64 pfn : 52;
> 6c94875799eaf9 Nadav Amit 2018-09-20 @200 } __packed;

And the error seems non-sensical to me: it appears the number of bits was mistakenly
considered as the name of the field by the test.