Re: [PATCH v5 2/5] misc: fastrpc: Remove buffer from list prior to unmap operation

[Greg KH]

On Fri, May 22, 2026 at 02:55:29PM +0800, Jianping Li wrote:
> 
> On 5/15/2026 9:36 PM, Dmitry Baryshkov wrote:
> > On Fri, May 15, 2026 at 08:42:14PM +0800, Jianping Li wrote:
> > > From: Ekansh Gupta<ekansh.gupta@xxxxxxxxxxxxxxxx>
> > > 
> > > fastrpc_req_munmap_impl() is called to unmap any buffer. The buffer is
> > > getting removed from the list after it is unmapped from DSP. This can
> > > create potential race conditions if any other thread removes the entry
> > > from list while unmap operation is ongoing. Remove the entry before
> > How can it remove the entry from the list?
> 
> Multiple threads sharing the same file descriptor may invoke unmap concurrently.

multiple threads sharing the same file descriptor is a horrible
userspace bug.  If you do that, you get what you deserve :)

thanks,

greg k-h