linux-6.15-rc2/drivers/xen/balloon.c:346: Possible int/long mixup

linux-6.15-rc2/drivers/xen/balloon.c:346: Possible int/long mixup

[David Binderman]

Hello there,

Static analyser cppcheck says:

linux-6.15-rc2/drivers/xen/balloon.c:346:24: style: int result is assigned to long variable. If the variable is long to avoid loss of information, then you have loss of information. [truncLongCastAssignment]

Source code is

    unsigned long i, size = (1 << order);

Maybe better code:

    unsigned long i, size = (1UL << order);

Regards

David Binderman

Re: linux-6.15-rc2/drivers/xen/balloon.c:346: Possible int/long mixup

[Jürgen Groß]

[-- Attachment #1.1.1: Type: text/plain, Size: 684 bytes --]

On 14.04.25 19:57, David Binderman wrote:
> Hello there,
> 
> Static analyser cppcheck says:
> 
> linux-6.15-rc2/drivers/xen/balloon.c:346:24: style: int result is assigned to long variable. If the variable is long to avoid loss of information, then you have loss of information. [truncLongCastAssignment]
> 
> Source code is
> 
>      unsigned long i, size = (1 << order);
> 
> Maybe better code:
> 
>      unsigned long i, size = (1UL << order);
> 

While I agree this would be better, there is no real failure possible
here. For this to cause problems you'd need to hotplug 16TB of memory
in one single block.

Nevertheless thanks for the notice.


Juergen

[-- Attachment #1.1.2: OpenPGP public key --]
[-- Type: application/pgp-keys, Size: 3743 bytes --]

[-- Attachment #2: OpenPGP digital signature --]
[-- Type: application/pgp-signature, Size: 495 bytes --]