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linux-kernel@vger.kernel.org Date: Tue, 21 Apr 2026 08:16:24 -0400 In-Reply-To: References: <20260407143306.78809-1-shuvampandey1@gmail.com> <20260419153111.90635-1-shuvampandey1@gmail.com> <150cda6feffe0826cfd43e5d8f0b4199b6268486.camel@HansenPartnership.com> Autocrypt: addr=James.Bottomley@HansenPartnership.com; prefer-encrypt=mutual; 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AHBLpBdnl9SOe8ETkv6GqbZrXUED/dAbRVIT5vHP51zyYB8rAUjp3PnzxsXFG8eQaacEyKSl0DKDlgKuQ+k292LVGJhEva8z4cwg3JcrQWzbpTRskQRP624aQ7t0LKbNfXqfYT13TvZNTDdjQaCJRJ3EG8uXOszVKuc0guXunZPmmq6x1Y3bOfOezcFYoywwL3nKef+Z5sQrjG3/5NLeu+W Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable User-Agent: Evolution 3.50.3 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 On Tue, 2026-04-21 at 07:53 +0300, Andy Shevchenko wrote: > On Tue, Apr 21, 2026 at 6:38=E2=80=AFAM Shuvam Pandey > wrote: >=20 > > > Well firstly I would note that the original behaviour isn't a > > > bug. >=20 > James, thank you for the prompt reply! >=20 > > So I agree this should not go forward as a bug fix in its current > > form. I'll drop this patch here and revisit it only if I can come > > back with a better understanding of the intended semantics. >=20 > Shuvam, perhaps we need to add a few more test cases first to > understand current behaviour better? Sure, but the base 2 one is the problem. It will go up to 1023 in whatever units but for binary that's under 1 of the next unit up. So 1023 B =3D=3D 1.00 KiB 1018 B =3D=3D 0.99 KiB 1000 B =3D=3D 0.98 KiB And so on. However, technically the latter two (when converted to the upper unit) are only 2sf not 3 because the leading zero doesn't count. If you run the above to 3sf it comes out 1023 B =3D=3D 0.999 KiB 1018 B =3D=3D 0.994 KiB 1000 B =3D=3D 0.977 KiB If the desire is really to be 3sf everywhere, you need the latter and the routine can be adjusted to do that: the while around the do_div would have to be checking strictly >=3D 1000 and you now have to set j=3D0 if size comes out 0. Rounding also has to be done inside that loop now (because too much precision is lost in the j =3D 3 case). But, like I said, this isn't a bug fix it's a behaviour change. Regards, James