[PATCH] arm64: mm: warn once for ioremap attempts on RAM mappings
Catalin Marinas
catalin.marinas at arm.com
Fri Jan 16 04:06:31 PST 2026
On Mon, Dec 22, 2025 at 07:28:55AM -0800, Breno Leitao wrote:
> Replace WARN_ON with WARN_ONCE when detecting attempts to ioremap
> RAM. This prevents log spam when a misbehaving driver repeatedly tries
> to map RAM via ioremap.
>
> A single warning is more than enough to show the broken code path, and
> extra reports don't add extra information.
>
> Warning floods have been seen in production environments where broken
> external drivers hit this code path thousand of times, causing
> unnecessary messages to be printed and pressure on the serial console.
>
> Signed-off-by: Breno Leitao <leitao at debian.org>
It looks fine to me but it's not urgent for 6.19, so I'll leave it to
Will.
Acked-by: Catalin Marinas <catalin.marinas at arm.com>
More information about the linux-arm-kernel
mailing list