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Peter Anvin" , Linus Torvalds , Peter Zijlstra , Thomas Gleixner , Borislav Petkov , Luc Van Oostenryck Content-Transfer-Encoding: quoted-printable Message-Id: <2EF46123-30B0-4A7E-9414-EE25CBCF255E@gmail.com> References: <20240812115945.484051-1-ubizjak@gmail.com> <20240812115945.484051-3-ubizjak@gmail.com> To: Uros Bizjak X-Mailer: Apple Mail (2.3776.700.51) > On 12 Aug 2024, at 14:57, Uros Bizjak wrote: > Assorted fixes to prevent defconfig build failures when > strict percpu address space checks will be enabled. >=20 > These show effeciveness of strict percpu address space checks. [snip] > --- a/drivers/base/devres.c > +++ b/drivers/base/devres.c > @@ -1231,6 +1231,6 @@ void devm_free_percpu(struct device *dev, void = __percpu *pdata) > * devm_free_pages() does. > */ > WARN_ON(devres_release(dev, devm_percpu_release, = devm_percpu_match, > - (__force void *)pdata)); > + (__force void *)(uintptr_t)pdata)); >=20 Since this pattern of casting appears multiple times (sometimes slightly different), I think it would be best to give a name for this operation and put it behind a macro. This would allow both to audit the cases developers move data between address-spaces, and also make them think whether what they do makes sense.