On Thu, 23 Jan 2025, Ivan Kokshaysky wrote: > > Indeed, SP_OFF in entry.S is the main suspect at the moment. > > In fact, it's the odd number of longs (29) in struct pt_regs that makes > the stack misaligned by 8 bytes. The patch below works for me - no more > oopses in rcu-torture test. > > Unless I'm missing something, this change shouldn't have any ill effects. Umm, this is a part of UAPI, and the change in alignment changes the ABI (think padding where `struct pt_regs' has been embedded into another structure), so AFAICT it is a no-no. But the only place I could quickly find this should matter for is this: /* ... and find our stack ... */ lda $30,0x4000 - SIZEOF_PT_REGS($8) which should be straightforward to fix: lda $30,0x4000 - ((SIZEOF_PT_REGS + 15) & ~15)($8) or suchlike. Have I missed anything? Maciej
