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>>>>>> cma->nranges = 1; >>>>>> cma->nid = NUMA_NO_NODE; >>>>>> + set_bit(CMA_FIXED_BASE, &cma->flags); >>>>>> *res_cma = cma; >>>>>> @@ -517,6 +531,8 @@ static int __init __cma_declare_contiguous_nid(phys_addr_t *basep, >>>>>> } >>>>>> (*res_cma)->nid = nid; >>>>>> + if (!fixed) >>>>>> + clear_bit(CMA_FIXED_BASE, &(*res_cma)->flags); >>>>> >>>>> Nit: This reads a bit odd. cma_init_reserved_mem() sets the fixed base >>>>> and then you clear it later. Wouldn't it be better to just pass the >>>>> fixed boolean to cma_init_reserved_mem()? >>>> >>>> Actually, we shouldn't expose cma_init_reserved_mem() at all. >>>> >>>> The current callers of cma_init_reserved_mem() should be switched to >>>> cma_declare_contiguous_nid() that does sanity checks before calling >>>> cma_init_reserved_mem(). >> >> Thanks Pratyush and Mike for the review. >> >> The switch from cma_init_reserved_mem() to cma_declare_contiguous_nid() >> looks like a broader CMA refactoring and requires additional changes to work >> correctly. > > Hmm, you are right. > > How about we invert the flag meaning? > Than cma_declare_contiguous_* will set it where appropriate and we won't > have the weirdness Pratyush pointed out. That's a good point. I will invert the flag meaning - something like. __cma_declare_contiguous_nid() + if (!fixed) + set_bit(CMA_DYNAMIC_BASE, &(*res_cma)->flags); So the v2 series would look like: mm/cma: drop the duplicate alignment check in rmem_cma_setup() of: reserved_mem: keep the reservation when node_init returns -EBUSY mm/cma: reject CMA areas that overlap the kernel image kexec: do not place the next kernel in a fixed-address CMA area > > And Radhey, please, make your LLM to spill more concise and to the point > text and teach it to trim emails ;-) Noted. Will take care of it in next version. Thanks, Radhey