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x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Stat-Signature: am1nh967mcajojj953pxoq87ukped37h X-Rspam-User: X-Rspamd-Queue-Id: F1607120003 X-Rspamd-Server: rspam02 X-HE-Tag: 1782624846-555092 X-HE-Meta: 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 1hB4b+Ux I+ETBRMd9mdL1Vw3W5U2IbyOJXyp1DKHZQ5hBHjOZv5ikFqNb7piY4/q6j9cDlrOYmdhXWCkp9qE8AQa2niCe7cQZp/ItDYNuymPXJ3a0gHxknECZ4wZ4cK+dxT7QikaVderX4SMPR1nps3OC+PPeAZgVQSJ8rtM3m9TRXEyZBjuCPh55D1FMS0n6gBwTWWo4GI4lpiGKyciKabN55215XrTo8jK5y/7g3XzlQW03lYxb80/QkTV7F9FXe/qc8rKxTVJitnMPRJ9x+Csw7tLy5w6U9sdSch/3jMfKE5cTj1A6ZXLWSQmwVIEETK7zJhvIv8RVpBMORdnOMrWI8DCjwG2tPGwKQdqnuAVpWMdEgL9kuOwHR5Y23R7nHbTUcUy+WuMVopNZ0D4IhtX9gQql36gOiu9gBc3scRndUrkVfmIlHuw= Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Thu, 11 Jun 2026 06:56:07 -0700 SeongJae Park wrote: > On Thu, 11 Jun 2026 14:56:57 +0200 Arnd Bergmann wrote: > > > From: Arnd Bergmann > > > > The main thread function has recently grown to the point of > > exceeding stack frame size warning limits in some configurations. > > This is what I hit on s390 with clang and CONFIG_KASAN: > > > > mm/damon/core.c:3440:31: error: stack frame size (1352) exceeds limit (1280) in 'kdamond_fn' [-Werror,-Wframe-larger-than] > > 3440 | static int kdamond_fn(struct damon_ctx *ctx) Well cheers to s390 for using a nice tight stack limit. > > The largest stack usage here is inside of the kdamond_tune_intervals(), > > so by marking that one as noinline_for_stack, the functions individually > > stay below the warning limit, though kdamond_fn() itself still uses > > hundreds of kilobytes for some reason. Wait what wut. This cannot mean that kdamond_fn() uses x00,000 bytes of stack, so what does it mean? > Thank you for this fix, Arnd! I will also take a look in kdamond_fn() to see > if there are more things to reduce. > > > > > Signed-off-by: Arnd Bergmann > > Reviewed-by: SeongJae Park > > Should we add Fixes: and Cc: stable@ too? This function was introduced by > commit f04b0fedbe71 ("mm/damon/core: implement intervals auto-tuning") which > was merged into 6.15. I don't think so - kernel is full of these offenders and it will be a long and painstaking process to weed them out.