acct(2): begin the deprecation of legacy BSD process accounting

As Christian points out [1], even though it's privileged, this interface
has a lot of footguns. There are better options these days (e.g. eBPF),
so it would be good to start discouraging its use and mark it as
deprecated.

[1]: https://lore.kernel.org/linux-fsdevel/20250212-giert-spannend-8893f1eaba7d@brauner/

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Link: https://patch.msgid.link/20260106-bsd-acct-v1-1-d15564b52c83@kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>

diff --git a/init/Kconfig b/init/Kconfig
index fa79feb8fe57bb01d8ce8f35e33535709b57d452..160c1c4ef253593d62650cd5a53f3421bc9372d3 100644 (file)
--- a/init/Kconfig
+++ b/init/Kconfig
@@ -624,8 +624,9 @@ config SCHED_HW_PRESSURE
          arch_update_hw_pressure() and arch_scale_thermal_pressure().
 
 config BSD_PROCESS_ACCT
-       bool "BSD Process Accounting"
+       bool "BSD Process Accounting (DEPRECATED)"
        depends on MULTIUSER
+       default n
        help
          If you say Y here, a user level program will be able to instruct the
          kernel (via a special system call) to write process accounting
@@ -635,7 +636,9 @@ config BSD_PROCESS_ACCT
          command name, memory usage, controlling terminal etc. (the complete
          list is in the struct acct in <file:include/linux/acct.h>).  It is
          up to the user level program to do useful things with this
-         information.  This is generally a good idea, so say Y.
+         information.  This mechanism is antiquated and has significant
+         scalability issues.  You probably want to use eBPF instead.  Say
+         N unless you really need this.
 
 config BSD_PROCESS_ACCT_V3
        bool "BSD Process Accounting version 3 file format"