Since commit 37a183d3b7cdb873 ("tcp: Convert tcp-md5 to use MD5 library
instead of crypto_ahash"), TCP_SIGPOOL is only selected by TCP_AO.
However, the latter depends on 64BIT, so tcp_sigpool can no longer be
built on 32-bit platforms at all.

Improve compile coverage on 32-bit by allowing the user to enable
TCP_SIGPOOL when compile-testing.  Add a dependency on CRYPTO, which is
always fulfilled when selected by TCP_AO.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
---
One remaining oddity is that TCP_SIGPOOL has always been a tristate
symbol, while all users that select it have always been boolean symbols.
I kept that as-is, as it builds fine as a module.
---
 net/ipv4/Kconfig | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/net/ipv4/Kconfig b/net/ipv4/Kconfig
index b71c22475c515ffc..7280d1b1dae1ba53 100644
--- a/net/ipv4/Kconfig
+++ b/net/ipv4/Kconfig
@@ -743,7 +743,8 @@ config DEFAULT_TCP_CONG
 	default "cubic"
 
 config TCP_SIGPOOL
-	tristate
+	tristate "TCP: Per-CPU pool of crypto requests" if COMPILE_TEST
+	depends on CRYPTO
 
 config TCP_AO
 	bool "TCP: Authentication Option (RFC5925)"
-- 
2.43.0

On Thu, Dec 04, 2025 at 03:57:31PM +0100, Geert Uytterhoeven wrote:
> Since commit 37a183d3b7cdb873 ("tcp: Convert tcp-md5 to use MD5 library
> instead of crypto_ahash"), TCP_SIGPOOL is only selected by TCP_AO.
> However, the latter depends on 64BIT, so tcp_sigpool can no longer be
> built on 32-bit platforms at all.
> 
> Improve compile coverage on 32-bit by allowing the user to enable
> TCP_SIGPOOL when compile-testing.  Add a dependency on CRYPTO, which is
> always fulfilled when selected by TCP_AO.
> 
> Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
> ---
> One remaining oddity is that TCP_SIGPOOL has always been a tristate
> symbol, while all users that select it have always been boolean symbols.
> I kept that as-is, as it builds fine as a module.

Hi Geert,

I tested some of the COMPILE_TEST/TCP_AO
combinations and this seems to work as expected.

Reviewed-by: Simon Horman <horms@kernel.org>

However,

## Form letter - net-next-closed

The merge window for v6.19 has begun and therefore net-next has closed
for new drivers, features, code refactoring and optimizations. We are
currently accepting bug fixes only.

Please repost when net-next reopens.

Due to a combination of the merge-window, travel commitments of the
maintainers, and the holiday season, net-next will re-open after
2nd January.

RFC patches sent for review only are welcome at any time.

See: https://www.kernel.org/doc/html/next/process/maintainer-netdev.html#development-cycle

-- 
pw-bot: defer