Re: [PATCH] binfmt_misc: pass binfmt_misc P flag to the interpreter

[Florian Weimer]

* YunQiang Su:

> Florian Weimer <fw@xxxxxxxxxxxxx> ä2020å3æ6æåä äå7:42åéï
>>
>> * YunQiang Su:
>>
>> > AT_* only has 32 slot and now. I was afraid that maybe we shouldn't take one.
>> >    /* AT_* values 18 through 22 are reserved */
>> >    27,28,29,30 are not used now.
>> > Which should we use?
>>
>> Where does this limit of 32 tags come from?  I don't see it from a
>> userspace perspective.
>
> Sorry it is my mistake: In linux/auxvec.h, I saw
>
> #define AT_RANDOM 25    /* address of 16 random bytes */
> #define AT_HWCAP2 26    /* extension of AT_HWCAP */
>
> #define AT_EXECFN  31   /* filename of program */
>
> The number jump to 31 from 26.
>
> It is my fault: in x86_64-linux-gnu/bits/auxv.h, the max number is 47 now.

So AT_* tags aren't a scarce resource after all?