Re: [PATCH v3] ARM: imx: Fix suspend/resume crash with Clang CFI

Yo'av Moshe <[email protected]> Sun, 26 Jul 2026 17:36:37 +0200
Newsgroups dev.linux.lists.llvm,dev.linux.lists.imx,org.infradead.lists.linux-arm-kernel,org.kernel.vger.linux-kernel,org.kernel.vger.stable
Message-ID <[email protected]>
On 2026-07-24 10:49 PM, Nick Desaulniers wrote:
> Yeah, Yo'av did you test further modifications that explicitly copy
> the hash prefix? I assumed Nathan's change _plus some additional tweak
> to copy not just imx6_suspend to OCRAM which I assume the code already
> does, but I would imagine you need another change to copy
> __kcfi_typeid_imx6_suspend into OCRAM just before the function.  Was
> that tested?
Yes, I tried that as well and it unfortunately didn't work.

I tested Nathan's change along with explicitly copying the 4-byte
prefix from before imx6_suspend into OCRAM right before calling fncpy().
However, when checking the compiled binary, "&imx6_suspend - 4" just
contained padding rather than the hash, so the copied 4-byte value
didn't match what the call site expected.

Yo'av