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R. Silva" , Tejun Heo , Zefan Li , Johannes Weiner Cc: cgroups@vger.kernel.org, linux-kernel@vger.kernel.org, linux-hardening@vger.kernel.org References: From: "Gustavo A. R. Silva" In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-AntiAbuse: This header was added to track abuse, please include it with any abuse report X-AntiAbuse: Primary Hostname - gator4166.hostgator.com X-AntiAbuse: Original Domain - vger.kernel.org X-AntiAbuse: Originator/Caller UID/GID - [47 12] / [47 12] X-AntiAbuse: Sender Address Domain - embeddedor.com X-BWhitelist: no X-Source-IP: 187.162.21.192 X-Source-L: No X-Exim-ID: 1qVzKQ-000zkG-1t X-Source: X-Source-Args: X-Source-Dir: X-Source-Sender: 187-162-21-192.static.axtel.net ([192.168.15.8]) [187.162.21.192]:60524 X-Source-Auth: gustavo@embeddedor.com X-Email-Count: 2 X-Org: HG=hgshared;ORG=hostgator; X-Source-Cap: Z3V6aWRpbmU7Z3V6aWRpbmU7Z2F0b3I0MTY2Lmhvc3RnYXRvci5jb20= X-Local-Domain: yes X-CMAE-Envelope: MS4xfAaNf5TGVhVIzLT3ij7nokBqaNhdLRWxItiwRpDjebni+LxKVD45CwHn7Y6Kx9nzfk6seSSl/QfnviXcIQG39WlTL6dAAJd54nh8X+ZAMby/JBeQA7EV UZZz6ev/KJ4anEdlCqXcqSLpSXMZVzJ4qqfebT0bPWbNGiSTzhuHHF/LBBYop1VTv494heOgV5JYD21N4K4Qt5kt2qPCHedOcWqiDphdwjWpc70C2E5dH+Pw Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi all, I wonder if you have any suggestions on how to address this issue. As it seems that my last attempt caused some boot failures[1][2]. At first, I thought that the right way to fix this was through a similar fix as this one[3]. But it seems I'm missing something else that I cannot determine yet. These -Wstringop-overflow warnings are mostly the last ones remaining before we can finally enable this compiler option, globally. Any help or advice on how to properly address this is greatly appreciated. :) Thanks! -- Gustavo [1] https://lore.kernel.org/linux-hardening/726aae97-755d-9806-11d4-2fb21aa93428@arm.com/ [2] https://lore.kernel.org/linux-hardening/361c2f87-1424-f452-912f-0e4a339f5c46@kernel.org/ [3] https://git.kernel.org/linus/d20d30ebb199 On 6/14/23 19:18, Gustavo A. R. Silva wrote: > Address the following -Wstringop-overflow warnings seen when > built with ARM architecture and aspeed_g4_defconfig configuration > (notice that under this configuration CGROUP_SUBSYS_COUNT == 0): > kernel/cgroup/cgroup.c:1208:16: warning: 'find_existing_css_set' accessing 4 bytes in a region of size 0 [-Wstringop-overflow=] > kernel/cgroup/cgroup.c:1258:15: warning: 'css_set_hash' accessing 4 bytes in a region of size 0 [-Wstringop-overflow=] > kernel/cgroup/cgroup.c:6089:18: warning: 'css_set_hash' accessing 4 bytes in a region of size 0 [-Wstringop-overflow=] > kernel/cgroup/cgroup.c:6153:18: warning: 'css_set_hash' accessing 4 bytes in a region of size 0 [-Wstringop-overflow=] > > These changes are based on commit d20d30ebb199 ("cgroup: Avoid compiler > warnings with no subsystems"). > > Signed-off-by: Gustavo A. R. Silva > --- > kernel/cgroup/cgroup.c | 6 ++++++ > 1 file changed, 6 insertions(+) > > diff --git a/kernel/cgroup/cgroup.c b/kernel/cgroup/cgroup.c > index cd497b90e11a..1ee76e62eb98 100644 > --- a/kernel/cgroup/cgroup.c > +++ b/kernel/cgroup/cgroup.c > @@ -1200,6 +1200,9 @@ static struct css_set *find_css_set(struct css_set *old_cset, > unsigned long key; > int ssid; > > + if (!CGROUP_HAS_SUBSYS_CONFIG) > + return NULL; > + > lockdep_assert_held(&cgroup_mutex); > > /* First see if we already have a cgroup group that matches > @@ -6045,6 +6048,9 @@ int __init cgroup_init(void) > struct cgroup_subsys *ss; > int ssid; > > + if (!CGROUP_HAS_SUBSYS_CONFIG) > + return -EINVAL; > + > BUILD_BUG_ON(CGROUP_SUBSYS_COUNT > 16); > BUG_ON(cgroup_init_cftypes(NULL, cgroup_base_files)); > BUG_ON(cgroup_init_cftypes(NULL, cgroup_psi_files));