Andreas Schwab wrote:

Richard Knutsson [off-list ref] writes:
  

quoted

Andreas Schwab wrote:
    

quoted

Richard Knutsson [off-list ref] writes:
  
      

quoted

Vignesh Babu BM wrote:
        

quoted

@@ -175,7 +176,7 @@ static int __init hugetlb_setup_sz(char *str)
 		tr_pages = 0x15557000UL;
  	size = memparse(str, &str);
-	if (*str || (size & (size-1)) || !(tr_pages & size) ||
+	if (*str || !is_power_of_2(size) || !(tr_pages & size) ||
 		size <= PAGE_SIZE ||
 		size >= (1UL << PAGE_SHIFT << MAX_ORDER)) {
 		printk(KERN_WARNING "Invalid huge page size specified\n");
          

As we talked about before; is this really correct? !is_power_of_2(0) ==
true while (0 & (0-1)) == 0.
        

size == 0 is also covered by the next two conditions, so the overall value
does not change.
      

Yes, but is it meant to state that 'size' is not a power of two?
    

What else can it mean?
  

What about !one_or_less_bit()? It has not been implemented (yet?) but 
been discussed. It ended by concluding that is_power_of_2() should be 
fixed up first and then we can see about it.
And as I stated before; !is_power_of_2(size) != (size & (size-1))! It 
may be a bug but then we have to be sure it is suppose to be the power of 2.

Richard Knutsson

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