Messages in this thread | | | From | Robert Jarzmik <> | Subject | Re: [PATCH] ARM: fix alignement of __bug_table section entries | Date | Sun, 06 Sep 2015 00:12:59 +0200 |
| |
Russell King - ARM Linux <linux@arm.linux.org.uk> writes:
>> Moreover, this is consistent with the fact that this commit is in linux-next but >> not in v4.1 : >> a5e090acbf54 ("ARM: software-based priviledged-no-access support") >> >> So the issue is around this SW_DOMAIN_PAN, at least on PXA. > > Is it only PXA which seems to be affected? Sorry I don't know, I only own pxa platforms.
> If so, you may need to add: > > mrc p15, 0, \rd, c2, c0, 0 > mov \rd, \rd > sub pc, pc, #4 > > to the places we update the domain access register to ensure that the > Xscale pipeline stalls to allow the CP15 DACR update to hit. Okay, I'll try that.
By the way, the ARMv5 manual states in chapter "B4.5.1 MMU Fault" that for a DACR update, a "PrefetchFlush" operation has to be done (chapter B2.6.3 PrefetchFlush CP15 register 7), quoting : Changes to the Domain Access Control register are synchronized by performing a PrefetchFlush operation (or as result of an exception or exception return). See Changes to CP15 registers and the memory order model on page B2-24 for details.
Cheers.
-- Robert
| |