----- On Apr 24, 2019, at 1:00 PM, Mathieu Desnoyers mathieu.desnoyers@xxxxxxxxxxxx wrote: > ----- On Apr 24, 2019, at 12:51 PM, Mark Rutland mark.rutland@xxxxxxx wrote: > >> On Wed, Apr 24, 2019 at 05:45:38PM +0100, Will Deacon wrote: >>> On Wed, Apr 24, 2019 at 11:25:00AM -0400, Mathieu Desnoyers wrote: >>> > +/* >>> > + * aarch64 -mbig-endian generates mixed endianness code vs data: >>> > + * little-endian code and big-endian data. Ensure the RSEQ_SIG signature >>> > + * matches code endianness. >>> > + */ >>> > +#define RSEQ_SIG_CODE 0xd428bc00 /* BRK #0x45E0. */ >>> > + >>> > +#ifdef __AARCH64EB__ >>> > +#define RSEQ_SIG_DATA 0x00bc28d4 /* BRK #0x45E0. */ >>> >>> It would be neater to implement swab32 and use that with RSEQ_SIG_CODE, >> >> If possible, marginally neater than that would be using >> le32_to_cpu(RSEQ_SIG_CODE), without any ifdeffery necessary. >> >> It looks like that's defined in tools/include/linux/kernel.h, but I'm >> not sure if that gets pulled into your include path. > > Considering that those RSEQ_SIG* define will end up in public bits/rseq.h > headers within glibc, I'm tempted to keep the amount of dependencies on > external headers to a minimum, if it's OK with you. Also, I'm not sure the le32_to_cpu() approach would work in __ASSEMBLER__ builds. Thanks, Mathieu > > Thanks, > > Mathieu > > -- > Mathieu Desnoyers > EfficiOS Inc. > http://www.efficios.com -- Mathieu Desnoyers EfficiOS Inc. http://www.efficios.com
