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charset=us-ascii Content-Disposition: inline In-Reply-To: <2025101610-detention-dangle-cef6@gregkh> On Thu, Oct 16, 2025 at 01:24:12PM +0200, Greg KH wrote: > On Thu, Oct 16, 2025 at 07:19:51PM +0900, Ryosuke Yasuoka wrote: > > On Wed, Oct 15, 2025 at 07:40:12AM +0200, Greg KH wrote: > > > On Wed, Oct 15, 2025 at 01:02:40PM +0900, Ryosuke Yasuoka wrote: > > > > Hi all, > > > > > > > > This patch series add support for the llseek file operation to misc > > > > devices written in Rust. > > > > > > Cool, but what miscdevice driver needs llseek support? Do you have a > > > real user for this that we can see as well? > > > > Currently no. Because lseek is one of fundamental functions for device > > driver, I think it's valuable to add support. I believe we'll have real > > users based on read, write, and this lseek support. > > Char devices that use lseek are "odd", don't you agree? There are no > such current users under drivers/misc/ and only a rare few under > drivers/char/ (the huge user of that is mem.c but we aren't going to be > reimplementing that in rust any time soon...) > > So without a real user of this api, I suggest we hold-off on adding it. > Let's not add it until someone comes up with a very valid reason for it. Thank you for your review and clear explanation. I understand your point. It makes sense not to add this without real user. I'll hold off on this and will revisit it if a concrete use case emerges. Best regards, Ryosuke > thanks, > > greg k-h >