On Tue, Aug 06, 2024 at 05:46:53PM +0200, Peter Zijlstra wrote: > On Tue, Aug 06, 2024 at 05:05:15PM +0200, Peter Zijlstra wrote: > > On Tue, Aug 06, 2024 at 04:56:32PM +0200, Peter Zijlstra wrote: > > > On Tue, Aug 06, 2024 at 07:25:42AM -0700, Guenter Roeck wrote: > > > > > > > I created http://server.roeck-us.net/qemu/x86-v6.11-rc2/ with all > > > > the relevant information. Please let me know if you need anything else. > > > > > > So I grabbed that config, stuck it in the build dir I used last time and > > > upgraded gcc-13 from 13.2 ro 13.3. But alas, my build runs successfully > > > :/ > > > > > > Is there anything else special I missed? > > > > run.sh is not exacrlty the same this time, different CPU model, that > > made it go. > > > > OK, lemme poke at this. > > Urgh, so crypto's late_initcall() does user-mode-helper based modprobe > looking for algorithms before we kick off /bin/init :/ > > This makes things difficult. > > Urgh. So the problem is that mark_readonly() splits a code PMD due to NX. Then the second pti_clone_entry_text() finds a kernel PTE but a user PMD mapping for the same address (from the early clone) and gets upset. And we can't run mark_readonly() sooner, because initcall expect stuff to be RW. But initcalls do modprobe, which runs user crap before we're done initializing everything. This is a right mess, and I really don't know what to do.
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