Hi! On Mon, 12 Mar 2007, Franck Bui-Huu wrote: > Date: Mon, 12 Mar 2007 18:05:10 +0100 > From: Franck Bui-Huu <vagabon.xyz@xxxxxxxxx> > To: post@xxxxxxxx > Cc: linux-mips@xxxxxxxxxxxxxx > Subject: Re: [PATCH 0/2] FLATMEM: allow memory to start at pfn != 0 [take > #2] > > On 3/12/07, peter fuerst <post@xxxxxxxx> wrote: > > > > You see the problem. Any occurrence of PAGE_OFFSET must be checked. > > > > yes and whatever the scheme you propose... > > > the kernel-addresses. Moreover it would be desirable, if this macro > > really could be used throughout the kernel, e.g. by drivers, handling > > any reasonable kernel-address, which isn't possible in the page_offset > > scheme anyway. > > > > Can you explain why the current use of pa() failed to handle all > kernel address with a real example ? Simply, when you convert between cached (kseg0, ckseg0, several xkphys- regions) and uncached (kseg1, ckseg1, several xkphys-regions) addresses and the other way round, you need the physical address as an intermediate value and __pa() or virt_to_phys() can support only one direction. Of course a scheme, that supports all unmapped spaces (kseg0/1, ckseg0/1, xkphys) simultaneously, or even xkphys alone, can't support TLB-mapped spaces (kseg3, ckseg3, ..., xkseg) - at which your patch seems to aim - and vice versa. > > A few people reported that they had problem with KPHYS/CKSEG0 address > mix for 64 bit kernels but as far I can see it was due to a miss > configuration of their kernels. Of course I canbe wrong but these Hmm, i don't remember actually mis-configured kernels, but allright, have to skim the eMail-archive again. > people haven't given any feedbacks so far... > > Thanks > -- > Franck kind regards peter
