Re: [PATCH] erofs: Fix EROFS_FS_ZIP_LZMA_DEFAULT_MAX_STREAMS default logic

From: Nicolas Schier

Date: Fri Aug 28 2026 - 15:21:41 EST


Cc: Julian

On Fri, Aug 28, 2026 at 07:21:07PM +0200, Geert Uytterhoeven wrote:
> Hi Nicolas,
>
> On Fri, 28 Aug 2026 at 17:47, Nicolas Schier <nsc@xxxxxxxxxx> wrote:
> > On Thu, Aug 20, 2026 at 12:15:33PM +0200, Geert Uytterhoeven wrote:
> > > On Thu, 20 Aug 2026 at 12:01, Geert Uytterhoeven
> > > <geert+renesas@xxxxxxxxx> wrote:
> > > > When NR_CPUS is less than 16, or when SMP is disabled, the default value
> > > > of 16 is invalid.
> > > >
> > > > While actual configuration picks up a sensible and valid default
> > > > (NR_CPUS or 1), "make savedefconfig" will still write a line like
> > > >
> > > > CONFIG_EROFS_FS_ZIP_LZMA_DEFAULT_MAX_STREAMS=1
> > > >
> > > > to the defconfig file, even if that matches the sensible default.
> > >
> > > Is this a bug in kconfig?
> >
> > I am not able to reproduce that; this is what I see with ARCH=arm64
> > (arm64 always has SMP=y):
>
> [...]
>
> > Thus, to me it looks as expected. Do you still see the behaviour you
> > described above?
>
> Perhaps you cannot reproduce this because this fix is already
> upstream as commit ab74edaeb1ae7c71 ("erofs: Fix
> EROFS_FS_ZIP_LZMA_DEFAULT_MAX_STREAMS default logic")?
>

oh sure, thanks. Yes, it really looks like a bug to me: if the range is
defined as 1 to 1, the default 16 should not cause a savedefconfig to
write the config set to 1.

--
Nicolas