From: "Paul E. McKenney" <paulmck@kernel.org> To: Dan Carpenter <dan.carpenter@oracle.com> Cc: rcu@vger.kernel.org Subject: Re: [bug report] EXP rcuscale: Add crude tests for mem_dump_obj() Date: Tue, 12 Jan 2021 10:07:28 -0800 Message-ID: <20210112180728.GJ2743@paulmck-ThinkPad-P72> (raw) In-Reply-To: <X/21KmJ1+jW+PJjC@mwanda> On Tue, Jan 12, 2021 at 05:41:46PM +0300, Dan Carpenter wrote: > Hello Paul E. McKenney, > > The patch b3a539cc4d37: "EXP rcuscale: Add crude tests for > mem_dump_obj()" from Dec 7, 2020, leads to the following static > checker warning: > > kernel/rcu/rcutorture.c:1888 rcu_torture_stats() > warn: did you mean to pass the address of 'rhp' > > kernel/rcu/rcutorture.c > 1865 { > 1866 struct rcu_head *rhp; > 1867 struct kmem_cache *kcp; > 1868 static int z; > 1869 > 1870 kcp = kmem_cache_create("rcuscale", 136, 8, SLAB_STORE_USER, NULL); > 1871 rhp = kmem_cache_alloc(kcp, GFP_KERNEL); > 1872 pr_alert("mem_dump_obj() slab test: rcu_torture_stats = %px, &rhp = %px, rhp = %px, &z = %px\n", stats_task, &rhp, rhp, &z); > ^^^^ > Hopefully the address of rhp doesn't change at all in this function 0_0! One would hope! The duplication makes it easier to check the output. Without it, it is necessary to get some information from the immediately preceding pr_alert() and others of it from the first pr_alert(). Thanx, Paul > 1873 pr_alert("mem_dump_obj(ZERO_SIZE_PTR):"); > 1874 mem_dump_obj(ZERO_SIZE_PTR); > 1875 pr_alert("mem_dump_obj(NULL):"); > 1876 mem_dump_obj(NULL); > 1877 pr_alert("mem_dump_obj(%px):", &rhp); > 1878 mem_dump_obj(&rhp); > 1879 pr_alert("mem_dump_obj(%px):", rhp); > 1880 mem_dump_obj(rhp); > 1881 pr_alert("mem_dump_obj(%px):", &rhp->func); > 1882 mem_dump_obj(&rhp->func); > 1883 pr_alert("mem_dump_obj(%px):", &z); > 1884 mem_dump_obj(&z); > 1885 kmem_cache_free(kcp, rhp); > 1886 kmem_cache_destroy(kcp); > 1887 rhp = kmalloc(sizeof(*rhp), GFP_KERNEL); > 1888 pr_alert("mem_dump_obj() kmalloc test: rcu_torture_stats = %px, &rhp = %px, rhp = %px\n", stats_task, &rhp, rhp); > 1889 pr_alert("mem_dump_obj(kmalloc %px):", rhp); > 1890 mem_dump_obj(rhp); > 1891 pr_alert("mem_dump_obj(kmalloc %px):", &rhp->func); > 1892 mem_dump_obj(&rhp->func); > 1893 kfree(rhp); > 1894 rhp = vmalloc(4096); > 1895 pr_alert("mem_dump_obj() vmalloc test: rcu_torture_stats = %px, &rhp = %px, rhp = %px\n", stats_task, &rhp, rhp); > 1896 pr_alert("mem_dump_obj(vmalloc %px):", rhp); > 1897 mem_dump_obj(rhp); > 1898 pr_alert("mem_dump_obj(vmalloc %px):", &rhp->func); > 1899 mem_dump_obj(&rhp->func); > 1900 vfree(rhp); > 1901 } > > regards, > dan carpenter
prev parent reply index Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top 2021-01-12 14:41 Dan Carpenter 2021-01-12 18:07 ` Paul E. McKenney [this message]
Reply instructions: You may reply publicly to this message via plain-text email using any one of the following methods: * Save the following mbox file, import it into your mail client, and reply-to-all from there: mbox Avoid top-posting and favor interleaved quoting: https://en.wikipedia.org/wiki/Posting_style#Interleaved_style * Reply using the --to, --cc, and --in-reply-to switches of git-send-email(1): git send-email \ --in-reply-to=20210112180728.GJ2743@paulmck-ThinkPad-P72 \ --to=paulmck@kernel.org \ --cc=dan.carpenter@oracle.com \ --cc=rcu@vger.kernel.org \ /path/to/YOUR_REPLY https://kernel.org/pub/software/scm/git/docs/git-send-email.html * If your mail client supports setting the In-Reply-To header via mailto: links, try the mailto: link
RCU Archive on lore.kernel.org Archives are clonable: git clone --mirror https://lore.kernel.org/rcu/0 rcu/git/0.git # If you have public-inbox 1.1+ installed, you may # initialize and index your mirror using the following commands: public-inbox-init -V2 rcu rcu/ https://lore.kernel.org/rcu \ rcu@vger.kernel.org public-inbox-index rcu Example config snippet for mirrors Newsgroup available over NNTP: nntp://nntp.lore.kernel.org/org.kernel.vger.rcu AGPL code for this site: git clone https://public-inbox.org/public-inbox.git