On 24/01/18 07:48, Wang YanQing wrote: > If we then OR this with 0x40, then the value of 6th bit (0th is first bit) > become known, so the right mask is 0xbf instead of 0xcf. > > Signed-off-by: Wang YanQing <udkni...@gmail.com> > --- > Documentation/networking/filter.txt | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/Documentation/networking/filter.txt > b/Documentation/networking/filter.txt > index 8781485..a4508ec 100644 > --- a/Documentation/networking/filter.txt > +++ b/Documentation/networking/filter.txt > @@ -1134,7 +1134,7 @@ The verifier's knowledge about the variable offset > consists of: > mask and value; no bit should ever be 1 in both. For example, if a byte is > read > into a register from memory, the register's top 56 bits are known zero, while > the low 8 are unknown - which is represented as the tnum (0x0; 0xff). If we > -then OR this with 0x40, we get (0x40; 0xcf), then if we add 1 we get (0x0; > +then OR this with 0x40, we get (0x40; 0xbf), then if we add 1 we get (0x0; > 0x1ff), because of potential carries. > Besides arithmetic, the register state can also be updated by conditional > branches. For instance, if a SCALAR_VALUE is compared > 8, in the 'true' > branch
Acked-by: Edward Cree <ec...@solarflare.com>
