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charset=UTF-8 Content-Transfer-Encoding: 7bit X-Rspam-User: X-Rspamd-Server: rspam03 X-Rspamd-Queue-Id: 60A9F120011 X-Stat-Signature: 3suwukjou69j33k71366zzukmetqtygn X-HE-Tag: 1741107436-62170 X-HE-Meta: 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 lIaNZEn6 EV0fchKIvDVYCxLw+Z99DcNRlL+mfcxvk/ywmCJcC9KzysOlzcZ3LGFtJOVMJHR33kux49HNSDRQfO4oMhjQaT5VQmzD+UT2crNCh22RgDLsQGqw4QghQGWZrIBhFQRlIQOGVcT/vH3BK4U1eRBUf2Vh+AXoczpBvOzv8jgYhgbGLJzU9fYq9eHOJQfkHPJPClLmZ/y8TZE9Cr8cbz+JjTyeqo2XximtBkcoj3evddxrcfBmObD9amM3dajji9F+7JjE1wQInWZiLVoHKr2VyEM3laQ== X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 3/4/25 08:19, Borislav Petkov wrote: > +static inline void __invlpgb_all(unsigned long asid, unsigned long pcid, > + unsigned long addr, u16 nr_pages, u8 flags) > +{ > + __invlpgb(asid, pcid, addr, nr_pages, 0, flags); > +} Why would __invlpg_all() need an 'addr' or 'nr_pages'? Shouldn't those be 0? It's _better_ of course when it happens at a single site and it's close to a prototype for __invlpgb(). But it's still a magic '0' that it's impossible to make sense of without looking at the prototype. Looking at the APM again... there really are three possible values for ECX[31]: 0: increment by 4k 1: increment by 2M X: Don't care, no increment is going to happen What you wrote above could actually be written: __invlpgb(asid, pcid, addr, nr_pages, 1, flags); so the 0/1 is _actually_ completely random and arbitrary as far as the spec goes. Why does it matter? It enables you to do sanity checking. For example, we could actually enforce a rule that "no stride" can't be paired with any of the per-address invalidation characteristics: if (stride == NO_STRIDE) { WARN_ON(flags & INVLPGB_FLAG_VA); WARN_ON(addr); WARN_ON(nr_pages); } That's impossible if you pass a 'bool' in. But, honestly, I'm deep into nitpick mode here. I think differentiating the three cases is worth it, but it's also not the hill I'm going to die on. ;)