Re: [PATCH -next] mm/hugetlb.c: fix printk format warning for 32-bit phys_addr_t

[Randy Dunlap <rdunlap@infradead.org>]

On 3/18/20 7:37 PM, Joe Perches wrote:
> On Wed, 2020-03-18 at 19:11 -0700, Randy Dunlap wrote:
>> On 3/18/20 7:04 PM, Joe Perches wrote:
>>> On Wed, 2020-03-18 at 14:33 -0700, Randy Dunlap wrote:
>>>> From: Randy Dunlap <rdunlap@infradead.org>
>>>>
>>>> Fix printk format warnings when phys_addr_t is 32 bits, i.e.,
>>>> CONFIG_PHYS_ADDR_T_64BIT is not set/enabled.
>>> []
>>>> ../mm/hugetlb.c:5472:73: note: format string is defined here
>>>>     pr_warn("hugetlb_cma: reservation failed: err %d, node %d, [%llu, %llu)",
>>>>                                                                       ~~~^
>>> []
>>>> --- linux-next-20200318.orig/mm/hugetlb.c
>>>> +++ linux-next-20200318/mm/hugetlb.c
>>>> @@ -5469,8 +5469,10 @@ void __init hugetlb_cma_reserve(int orde
>>>>  					     0, false,
>>>>  					     "hugetlb", &hugetlb_cma[nid]);
>>>>  		if (res) {
>>>> -			pr_warn("hugetlb_cma: reservation failed: err %d, node %d, [%llu, %llu)",
>>>> -				res, nid, PFN_PHYS(min_pfn), PFN_PHYS(max_pfn));
>>>> +			phys_addr_t begpa = PFN_PHYS(min_pfn);
>>>> +			phys_addr_t endpa = PFN_PHYS(max_pfn);
>>>> +			pr_warn("hugetlb_cma: reservation failed: err %d, node %d, [%pap, %pap)",
>>>> +				res, nid, &begpa, &endpa);
>>>
>>> You might correct the odd use of an open bracket
>>> then close parenthesis and add a new line too
>>
>> Definitely needs a newline char.
>>
>> I'm fairly sure that the [begin, end) notation is done on purpose, meaning
>> <begin> is included in the range and <end> is not included in the range.
> 
> OK, that seems a pretty obscure and not obvious use of
> interval notation, at least to me. (18 uses treewide ?)
> 
> Maybe it could be documented somewhere?

I thought about where to put that and came up empty.

> It's an odd pattern to grep.  Maybe I missed some.

It's probably not used much more than this.

> $ git grep -P '".*[\[\{]\s*%\d*[ldux]+\s*[/:,\.\-]?\s*%\d*[ldux]+\).*"'
> arch/x86/kernel/alternative.c:  DUMP_BYTES(instr, a->instrlen, "%px: [%d:%d) optimized NOPs: ",
> drivers/clk/qcom/clk-alpha-pll.c:               pr_err("%s: Rounded rate %lu not within range [%lu, %lu)\n",
> fs/ext4/extents_status.c:               printk(KERN_DEBUG " [%u/%u) %llu %x",
> fs/ext4/extents_status.c:                       es_debug("%u cached by [%u/%u) %llu %x\n",
> fs/ext4/extents_status.c:       es_debug("add [%u/%u) %llu %x to extent status tree of inode %lu\n",
> fs/ext4/extents_status.c:                       es_debug("%u cached by [%u/%u)\n",
> fs/ext4/extents_status.c:       es_debug("remove [%u/%u) from extent status tree of inode %lu\n",
> fs/nilfs2/cpfile.c:                       "cannot delete checkpoints: invalid range [%llu, %llu)",
> fs/nilfs2/dat.c:                          "%s: invalid vblocknr = %llu, [%llu, %llu)",
> include/trace/events/ext4.h:    TP_printk("dev %d,%d ino %lu es [%u/%u) mapped %llu status %s",
> include/trace/events/ext4.h:    TP_printk("dev %d,%d ino %lu es [%lld/%lld)",
> include/trace/events/ext4.h:    TP_printk("dev %d,%d ino %lu es [%u/%u) mapped %llu status %s",
> include/trace/events/ext4.h:    TP_printk("dev %d,%d ino %lu found %d [%u/%u) %llu %s",
> include/trace/events/ext4.h:    TP_printk("dev %d,%d ino %lu es [%u/%u) mapped %llu status %s "
> mm/hugetlb.c:                   pr_warn("hugetlb_cma: reservation failed: err %d, node %d, [%llu, %llu)",
> mm/kasan/report.c:              pr_err(" [%lu, %lu) '%s'", offset, offset + size, token);
> mm/page_alloc.c:                pr_info_ratelimited("%s: [%lx, %lx) PFNs busy\n",
> tools/testing/selftests/kvm/demand_paging_test.c:               PER_VCPU_DEBUG("Added VCPU %d with test mem gpa [%lx, %lx)\n",
> 
> 

thanks.

-- 
~Randy