On Thu, Jun 10, 2021 at 4:04 PM Helge Deller <deller@xxxxxx> wrote: > > Hi Masahiro, > > On 6/10/21 4:03 AM, Masahiro Yamada wrote: > > On Thu, Jun 10, 2021 at 7:50 AM Helge Deller <deller@xxxxxx> wrote: > >> > >> On 6/1/21 12:21 PM, Meelis Roos wrote: > >>> Upstream Linux git fails to compile on gentoo hppa - .config below. > >>> I have 2 gcc-s as always: > >>> $ gcc-config -l > >>> [1] hppa2.0-unknown-linux-gnu-9.3.0 > >>> [2] hppa2.0-unknown-linux-gnu-10.2.0 * > >>> > >>> [3] hppa64-unknown-linux-gnu-10.2.0 * > >> > >> > >> I see the same issue too, but only when compiling natively on a parisc machine. > >> Cross-compiling on a x86 box works nicely. > >> > >> First I thought it's a problem with setting the "cross_compiling" flag in ./Makefile. > >> But that's not sufficient. > >> > >> On a x86 machine (which builds fine) I get > >> SRCARCH=parisc SUBARCH=x86 UTS_MACHINE=parisc > >> The arch/parisc/kernel/asm-offsets.c file gets preprocessed via: > >> hppa64-linux-gnu-gcc > >> > >> On a native 32bit parisc machine I have: > >> SRCARCH=parisc SUBARCH=parisc UTS_MACHINE=parisc > >> Here the arch/parisc/kernel/asm-offsets.c file gets preprocessed via: > >> gcc > >> Instead here the native hppa64-linux-gnu-gcc (cross compiler) should have been used too, since > >> we build a 64-bit hppa kernel (CONFIG_64BIT is set). > >> Note, on hppa we don't have an "-m64" compiler flag as on x86. > > > > I see. > > hppa is not a bi-arch compiler, in other words, > > http- and hppa64- are separate compilers. > > Yes. > > >> Mashahiro, do you maybe have an idea what gets wrong here, or which > >> patch has changed the behaviour how the asm-offsets.c file gets preprocessed? > > > > Presumably, commit 23243c1ace9fb4eae2f75e0fe0ece8e3219fb4f3 > > > > Prior to that commit, arch/parisc/Makefile was like this: > > > > ifneq ($(SUBARCH),$(UTS_MACHINE)) > > ifeq ($(CROSS_COMPILE),) > > ... > > > > Now I understand why arch/parisc/Makefile was written this way. > > > > Reverting the change in arch/parisc/Makefile will restore the original behavior. > > Sadly, reverting this change (23243c1ace9fb4eae2f75e0fe0ece8e3219fb4f3) does not > restore the original behavior. > > > But, please keep in mind that there is an issue remaining. > > > > Please see this code: > > > > ifdef CONFIG_64BIT > > UTS_MACHINE := parisc64 > > CHECKFLAGS += -D__LP64__=1 > > CC_ARCHES = hppa64 > > LD_BFD := elf64-hppa-linux > > else # 32-bit > > CC_ARCHES = hppa hppa2.0 hppa1.1 > > LD_BFD := elf32-hppa-linux > > endif > > > > > > UTS_MACHINE is determined by CONFIG_64BIT. > > > > CONFIG_64BIT is defined only after Kconfig is finished. > > When you are trying to configure the .config, > > CONFIG_64BIT is not defined yet. > > So UTS_MACHINE is always 'parisc'. > > Yes. > See above, but it worked when I had SUBARCH=x86 (when running my laptop). > > > > As you know, Kconfig files now have a bunch of 'cc-option' syntax > > to check the compiler capability in Kconfig time. > > Hence, you need to provide a proper compiler in Kconfig time too. > > > > When you build a 64-bit parisc kernel on a 32-bit parisc machine, > > Please note, that we don't have a 64-bit parisc userspace yet (just kernel). > This means, that all builds on parisc machines are 32bit and do a > cross-compilation to a parisc64 kernel if requested in the .config. > > > Kconfig is passed with CC=gcc since SUBARCH==UTS_MACHINE==parisc. > > After Kconfig, CROSS_COMPILE=hppa64-* is set, > > and the kernel is built by CC=hppa64-*-gcc. > > Right. That is the old behaviour. Based on the CONFIG_64BIT option > the hppa64 compiler is choosen for CROSS_COMPILE. > > > So, Kconfig evaluated a compiletely different compiler. This is pointless. > > Yes, probably. > > > > There are some options > > > > [option 1] > > revert the parisc bit of 23243c1ace9fb4eae2f75e0fe0ece8e3219fb4f3 > > This will restore the functionality you may want, but > > as I said above, Kconfig is doing pointless things. > > as mentioned above: Doesn't solve the issue. > > > [option 2] > > Stop using cc-cross-prefix, and pass CROSS_COMPILE explicitly. > > This is what many architectures including arm, arm64 do. > > You need to explicitly pass CROSS_COMPILE=aarch64-linux-gnu- etc. > > if you are cross-compiling arm64. > > Might be an option, but it's not as handy as simply choosing CONFIG_64BIT > and then things are done automatically. > > > [option 3] > > Introduce ARCH=parisc64. > > > > When you are building 64-bit kernel, you can pass ARCH=parisc64 > > A patch attached. (but not tested much) > > Tried it, but doesn't work. > asm-offsets.c is still preprocessed with 32bit compiler (gcc, not hppa20-gcc). > > Thanks for your help so far! > If you like I'm happy to give you an account on a hppa64 machine to reproduce yourself. > I'll now try to bisect where it goes wrong. There must be something else before commit 23243c1ace9fb4eae2f75e0fe0ece8e3219fb4f3. > > Helge Sorry for my late reply. Did git-bisect find something? If necessary, I will be happy to try it on the hppa64 machine. -- Best Regards Masahiro Yamada
