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charset=us-ascii Content-Disposition: inline In-Reply-To: <20250620093102.2416767-1-hao.ge@linux.dev> X-Rspam-User: X-Rspamd-Queue-Id: 4C161180006 X-Rspamd-Server: rspam10 X-Stat-Signature: 3kxnxbaokqdndb6dycccfxbsfwckdfso X-HE-Tag: 1750416259-118849 X-HE-Meta: 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 j4EY1Snc EwwWPqAx/KqrezQzCJcp/Ue7OF7KFjf57MTuBVcTg96VvcHPFkTCyhnODve5tVDPUEhu7I5HZuKwXsVyhfHbHwCj0HRLFMsAY3uyTcqj7MU5dCV47yJ27JyZMUnN4VrsHmRMLQJOQIeDrWx5MHbLtv3eem96P1eRkatjiS95gmolEPe4Fn5HgCljtfhVtMhMErYOaFlPu3Tm7ZnOZEnCNZQ2FaXb37T3WTxbgNpwW3k9B2oL4eIcjScf16j3B31sdZiqeigO/Cc+DHNdZQfrnh6NOvA== 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: List-Subscribe: List-Unsubscribe: On Fri, Jun 20, 2025 at 05:31:02PM +0800, Hao Ge wrote: > From: Hao Ge > > When loading a module, as long as the module has memory > allocation operations, kmemleak produces a false positive > report that resembles the following: > > unreferenced object (percpu) 0x7dfd232a1650 (size 16): > comm "modprobe", pid 1301, jiffies 4294940249 > hex dump (first 16 bytes on cpu 2): > 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ > backtrace (crc 0): > kmemleak_alloc_percpu+0xb4/0xd0 > pcpu_alloc_noprof+0x700/0x1098 > load_module+0xd4/0x348 > codetag_module_init+0x20c/0x450 > codetag_load_module+0x70/0xb8 > load_module+0xef8/0x1608 > init_module_from_file+0xec/0x158 > idempotent_init_module+0x354/0x608 > __arm64_sys_finit_module+0xbc/0x150 > invoke_syscall+0xd4/0x258 > el0_svc_common.constprop.0+0xb4/0x240 > do_el0_svc+0x48/0x68 > el0_svc+0x40/0xf8 > el0t_64_sync_handler+0x10c/0x138 > el0t_64_sync+0x1ac/0x1b0 > > This is because the module can only indirectly reference alloc_tag_counters > through the alloc_tag section, which misleads kmemleak. > > However, we don't have a kmemleak ignore interface for percpu > allocations yet. So let's create one and invoke it for tag->counters. > > Fixes: 12ca42c23775 ("alloc_tag: allocate percpu counters for module tags dynamically") > Signed-off-by: Hao Ge Reviewed-by: Catalin Marinas