On 19/04/2023 15:19, Michal Orzel wrote: > > > Hi Ayan, > > On 13/04/2023 19:37, Ayan Kumar Halder wrote: >> >> >> The DT functions (dt_read_number(), device_tree_get_reg(), fdt_get_mem_rsv()) >> currently accept or return 64-bit values. >> >> In future when we support 32-bit physical address, these DT functions are >> expected to accept/return 32-bit or 64-bit values (depending on the width of >> physical address). Also, we wish to detect if any truncation has occurred >> (i.e. while parsing 32-bit physical addresses from 64-bit values read from >> DT). >> >> device_tree_get_reg() should now be able to return paddr_t. This is invoked >> by >> various callers to get DT address and size. >> >> For fdt_get_mem_rsv(), we have introduced a wrapper named >> fdt_get_mem_rsv_paddr() which will invoke fdt_get_mem_rsv() and translate >> uint64_t to paddr_t. The reason being we cannot modify fdt_get_mem_rsv() as >> it >> has been imported from external source. >> >> For dt_read_number(), we have also introduced a wrapper named dt_read_paddr() >> dt_read_paddr() to read physical addresses. We chose not to modify the >> original >> function as it is used in places where it needs to specifically read 64-bit >> values from dt (For e.g. dt_property_read_u64()). >> >> Xen prints warning when it detects truncation in cases where it is not able >> to >> return error. >> >> Also, replaced u32/u64 with uint32_t/uint64_t in the functions touched >> by the code changes. >> >> Also, initialized variables to fix the warning "-Werror=maybe-uninitialized". > I can see that now you explicitly set to 0 variables passed to > fdt_get_mem_rsv_paddr() > which haven't been initialized before being passed to fdt_get_mem_rsv(). Is > this what > you are reffering to? I cannot reproduce it, hence my question. I can see why did you get this error. Before your change, we always checked for an error from fdt_get_mem_rsv() by checking if < 0. In your wrapper fdt_get_mem_rsv_paddr(), you switched (not sure why) to checking if not zero. Becasue of this, you got an error and tried to fix it by initializing the variables to 0.
~Michal
