error: the frame size of 1552 bytes is larger than 1280 bytes when building bcachefs

[Arnd Bergmann]

On Thu, May 22, 2025, at 08:39, Peng Fan wrote:
> Hi Kent, Arnd
>
> There is below build error with "make ARCH=arm randconfig; make"
>
> fs/bcachefs/data_update.c: In function 
> '__bch2_data_update_index_update':
> fs/bcachefs/data_update.c:439:1: error: the frame size of 1552 bytes is 
> larger than 1280 bytes [-Werror=frame-larger-than=]

Right, I think that's been the case with bcachefs since the start,
and I see it with allmodconfig as well, the problem being mostly
CONFIG_KASAN_STACK.

There are a couple of bcachefs functions that have an unusual number
of local struct variables in them, and KASAN_STACK adds a redzone
around each one of them, further increasing the size.

When I add "depends on !KASAN_STACK" to bcachefs, I see all
randconfig builds succeeding, but that may not be the best
solution.

     Arnd