On Mon, Aug 03, 2020 at 01:31:27PM -0600, Rob Herring wrote: > @@ -979,6 +980,14 @@ > write_sysreg(__scs_new, sysreg); \ > } while (0) > > +#define read_sysreg_par() ({ \ > + u64 par; \ > + asm(ALTERNATIVE("nop", "dmb sy", ARM64_WORKAROUND_1508412)); \ > + par = read_sysreg(par_el1); \ > + asm(ALTERNATIVE("nop", "dmb sy", ARM64_WORKAROUND_1508412)); \ > + par; \ > +}) I was about to queue this up but one more point to clarify: can we get an interrupt at either side of the PAR_EL1 read and the handler do a device read, triggering the erratum? Do we need a DMB at exception entry/return? -- Catalin _______________________________________________ kvmarm mailing list kvmarm@xxxxxxxxxxxxxxxxxxxxx https://lists.cs.columbia.edu/mailman/listinfo/kvmarm