Re: [RFC V2 6/6] mm: Drop pxd_ERROR()

["David Hildenbrand (Arm)" <david@kernel.org>]

On 8/11/26 06:21, Anshuman Khandual wrote:
> pxd_ERROR() has been used in generic mm just to print the page table entry
> in pxd_clear_bad() before clearing those out with pxd_clear() later. These
> pxd_ERROR() macros have been provided by all platforms which basically did
> the same thing.
> 
> Make pxd_clear_bad() use recently added ptval_to_str() instead for printing
> page table entries thus completely dropping dependency on platform provided
> pxd_ERROR() macros which can then be dropped off. First move all required
> helpers in core MM into a header file which could then be used else where.
> 

It might make sense to split this patch further up to ease review:

Patch 1) provide ptval_to_str() a header.

Patch 2) Stop using pxd_ERROR() and friends in common code, converting to
pteval_to_str()

Patch 3) Remove now unused pxd_ERROR() and friends from arch code.

...
> +static inline void
> +ptval_bytes_to_hex_str(char *buf, size_t buf_size, const void *entry, size_t entry_size)
> +{
> +	if (WARN_ON_ONCE(buf_size < entry_size * 2 + 1)) {
> +		snprintf(buf, buf_size, "overflow");
> +		return;
> +	}
> +
> +	switch (entry_size) {
> +	case sizeof(u32):
> +		snprintf(buf, buf_size, "%08x", *(const u32 *)entry);
> +		break;
> +	case sizeof(u64):
> +		snprintf(buf, buf_size, "%016llx", *(const u64 *)entry);
> +		break;
> +#if defined(__SIZEOF_INT128__)
> +	case sizeof(u128):
> +		snprintf(buf, buf_size, "%016llx%016llx",
> +			 (unsigned long long)(*(const u128 *)entry >> 64),
> +			 (unsigned long long)*(const u128 *)entry);
> +		break;
> +#endif
> +	default:
> +		snprintf(buf, buf_size, "unsupported");
> +		break;
> +	}
> +}

Why not leave ptval_bytes_to_hex_str() in the C file for less churn for now?

-- 
Cheers,

David