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charset="UTF-8" X-Spamd-Result: default: False [5.57 / 9.00]; SORBS_IRL_BL(3.00)[209.85.215.174:from]; SUSPICIOUS_RECIPS(1.50)[]; SUBJECT_HAS_UNDERSCORES(1.00)[]; RCVD_NO_TLS_LAST(0.10)[]; MIME_GOOD(-0.10)[text/plain]; BAD_REP_POLICIES(0.10)[]; BAYES_HAM(-0.03)[50.57%]; R_DKIM_ALLOW(0.00)[google.com:s=20210112]; TAGGED_RCPT(0.00)[]; FROM_EQ_ENVFROM(0.00)[]; MIME_TRACE(0.00)[0:+]; RCVD_COUNT_TWO(0.00)[2]; RCPT_COUNT_TWELVE(0.00)[15]; R_SPF_ALLOW(0.00)[+ip4:209.85.128.0/17]; DMARC_POLICY_ALLOW(0.00)[google.com,reject]; TO_MATCH_ENVRCPT_SOME(0.00)[]; PREVIOUSLY_DELIVERED(0.00)[linux-mm@kvack.org]; DKIM_TRACE(0.00)[google.com:+]; ARC_SIGNED(0.00)[hostedemail.com:s=arc-20220608:i=1]; FROM_HAS_DN(0.00)[]; TO_DN_SOME(0.00)[]; ARC_NA(0.00)[] X-Rspam-User: X-Rspamd-Server: rspam04 X-Rspamd-Queue-Id: B0337100012 X-Stat-Signature: e9ri1i465bcatrpjhy9kjhcwa93cocu7 X-HE-Tag: 1670348973-577842 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Tue, Dec 6, 2022 at 8:35 AM Greg KH wrote: > > On Tue, Dec 06, 2022 at 08:26:30AM -0800, Jeff Xu wrote: > > On Tue, Dec 6, 2022 at 8:04 AM Greg KH wrote: > > > > > > On Tue, Dec 06, 2022 at 03:23:55PM +0000, jeffxu@chromium.org wrote: > > > > --- a/kernel/pid_namespace.c > > > > +++ b/kernel/pid_namespace.c > > > > @@ -110,6 +110,11 @@ static struct pid_namespace *create_pid_namespace(struct user_namespace *user_ns > > > > ns->ucounts = ucounts; > > > > ns->pid_allocated = PIDNS_ADDING; > > > > > > > > +#if defined(CONFIG_SYSCTL) && defined(CONFIG_MEMFD_CREATE) > > > > + ns->memfd_noexec_scope = > > > > + task_active_pid_ns(current)->memfd_noexec_scope; > > > > +#endif > > > > > > .c files should never have #if in them. Can't you put this in a .h file > > > properly so that this does not get really messy over time? > > > > > > > > Thanks for reviewing. > > It seems to me that checking for CONFIG_XXX is common in c code in > > kernel/ path. > > Maybe, but please don't make it any worse if at all possible. It's > tough to maintain code like that. > > > Do you have a sample code pattern (link/function) that I can follow? > > Any of the zillions of #if statements in .h files :) > Thanks. I will take the approach of having real/stub implementation in the h file, and the c file using it without a compile flag. Please kindly let me know if this is not right. Thanks Jeff > thanks, > > greg k-h