Hi Peter, Thank you for the patch! Perhaps something to improve: [auto build test WARNING on tip/sched/core] [also build test WARNING on bpf-next/master bpf/master linus/master v5.16-rc2] [cannot apply to arm64/for-next/core arm-perf/for-next/perf tip/core/entry next-20211123] [If your patch is applied to the wrong git tree, kindly drop us a note. And when submitting patch, we suggest to use '--base' as documented in https://git-scm.com/docs/git-format-patch] url: https://github.com/0day-ci/linux/commits/Peter-Collingbourne/kernel-intro... base: https://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git cb0e52b7748737b2cf6481fdd9b920ce7e1ebbdf config: x86_64-randconfig-s021-20211123 (https://download.01.org/0day-ci/archive/20211124/202111240417.oXKdhwgK-lk...) compiler: gcc-9 (Debian 9.3.0-22) 9.3.0 reproduce: # apt-get install sparse # sparse version: v0.6.4-dirty # https://github.com/0day-ci/linux/commit/7cd6f102201f3ea35eea1b990f7543e89... git remote add linux-review https://github.com/0day-ci/linux git fetch --no-tags linux-review Peter-Collingbourne/kernel-introduce-uaccess-logging/20211123-131922 git checkout 7cd6f102201f3ea35eea1b990f7543e890b7fdbb # save the config file to linux build tree make W=1 C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__' O=build_dir ARCH=x86_64 SHELL=/bin/bash If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp(a)intel.com&gt; sparse warnings: (new ones prefixed by >>) kernel/uaccess-buffer.c:72:31: sparse: expected struct spinlock [usertype] *lock kernel/uaccess-buffer.c:72:31: sparse: got struct spinlock [noderef] __rcu * kernel/uaccess-buffer.c:75:33: sparse: sparse: incorrect type in argument 1 (different address spaces) @@ expected struct spinlock [usertype] *lock @@ got struct spinlock [noderef] __rcu * @@ kernel/uaccess-buffer.c:75:33: sparse: expected struct spinlock [usertype] *lock kernel/uaccess-buffer.c:75:33: sparse: got struct spinlock [noderef] __rcu * kernel/uaccess-buffer.c:83:29: sparse: sparse: Using plain integer as NULL pointer kernel/uaccess-buffer.c:94:13: sparse: sparse: Using plain integer as NULL pointer kernel/uaccess-buffer.c:119:21: sparse: sparse: Using plain integer as NULL pointer vim +32 kernel/uaccess-buffer.c e050ed271bb0008 Peter Collingbourne 2021-11-22 17 e050ed271bb0008 Peter Collingbourne 2021-11-22 18 static void uaccess_buffer_log(unsigned long addr, unsigned long size, e050ed271bb0008 Peter Collingbourne 2021-11-22 19 unsigned long flags) e050ed271bb0008 Peter Collingbourne 2021-11-22 20 { e050ed271bb0008 Peter Collingbourne 2021-11-22 21 struct uaccess_buffer_info *buf = &current->uaccess_buffer; e050ed271bb0008 Peter Collingbourne 2021-11-22 22 struct uaccess_buffer_entry *entry = buf->kcur; e050ed271bb0008 Peter Collingbourne 2021-11-22 23 e050ed271bb0008 Peter Collingbourne 2021-11-22 24 if (!entry || unlikely(uaccess_kernel())) e050ed271bb0008 Peter Collingbourne 2021-11-22 25 return; e050ed271bb0008 Peter Collingbourne 2021-11-22 26 entry->addr = addr; e050ed271bb0008 Peter Collingbourne 2021-11-22 27 entry->size = size; e050ed271bb0008 Peter Collingbourne 2021-11-22 28 entry->flags = flags; e050ed271bb0008 Peter Collingbourne 2021-11-22 29 e050ed271bb0008 Peter Collingbourne 2021-11-22 30 ++buf->kcur; e050ed271bb0008 Peter Collingbourne 2021-11-22 31 if (buf->kcur == buf->kend) e050ed271bb0008 Peter Collingbourne 2021-11-22 @32 buf->kcur = 0; e050ed271bb0008 Peter Collingbourne 2021-11-22 33 } e050ed271bb0008 Peter Collingbourne 2021-11-22 34 e050ed271bb0008 Peter Collingbourne 2021-11-22 35 void uaccess_buffer_log_read(const void __user *from, unsigned long n) e050ed271bb0008 Peter Collingbourne 2021-11-22 36 { e050ed271bb0008 Peter Collingbourne 2021-11-22 37 uaccess_buffer_log((unsigned long)from, n, 0); e050ed271bb0008 Peter Collingbourne 2021-11-22 38 } e050ed271bb0008 Peter Collingbourne 2021-11-22 39 EXPORT_SYMBOL(uaccess_buffer_log_read); e050ed271bb0008 Peter Collingbourne 2021-11-22 40 e050ed271bb0008 Peter Collingbourne 2021-11-22 41 void uaccess_buffer_log_write(void __user *to, unsigned long n) e050ed271bb0008 Peter Collingbourne 2021-11-22 42 { e050ed271bb0008 Peter Collingbourne 2021-11-22 43 uaccess_buffer_log((unsigned long)to, n, UACCESS_BUFFER_FLAG_WRITE); e050ed271bb0008 Peter Collingbourne 2021-11-22 44 } e050ed271bb0008 Peter Collingbourne 2021-11-22 45 EXPORT_SYMBOL(uaccess_buffer_log_write); e050ed271bb0008 Peter Collingbourne 2021-11-22 46 e050ed271bb0008 Peter Collingbourne 2021-11-22 47 int uaccess_buffer_set_descriptor_addr_addr(unsigned long addr) e050ed271bb0008 Peter Collingbourne 2021-11-22 48 { e050ed271bb0008 Peter Collingbourne 2021-11-22 49 current->uaccess_buffer.desc_ptr_ptr = e050ed271bb0008 Peter Collingbourne 2021-11-22 50 (struct uaccess_descriptor __user * __user *)addr; e050ed271bb0008 Peter Collingbourne 2021-11-22 51 uaccess_buffer_cancel_log(current); e050ed271bb0008 Peter Collingbourne 2021-11-22 52 return 0; e050ed271bb0008 Peter Collingbourne 2021-11-22 53 } e050ed271bb0008 Peter Collingbourne 2021-11-22 54 e050ed271bb0008 Peter Collingbourne 2021-11-22 55 bool __uaccess_buffer_pre_exit_loop(void) e050ed271bb0008 Peter Collingbourne 2021-11-22 56 { e050ed271bb0008 Peter Collingbourne 2021-11-22 57 struct uaccess_buffer_info *buf = &current->uaccess_buffer; e050ed271bb0008 Peter Collingbourne 2021-11-22 58 struct uaccess_descriptor __user *desc_ptr; e050ed271bb0008 Peter Collingbourne 2021-11-22 59 sigset_t tmp_mask; e050ed271bb0008 Peter Collingbourne 2021-11-22 60 e050ed271bb0008 Peter Collingbourne 2021-11-22 61 if (get_user(desc_ptr, buf->desc_ptr_ptr) || !desc_ptr) e050ed271bb0008 Peter Collingbourne 2021-11-22 62 return false; e050ed271bb0008 Peter Collingbourne 2021-11-22 63 e050ed271bb0008 Peter Collingbourne 2021-11-22 64 current->real_blocked = current->blocked; e050ed271bb0008 Peter Collingbourne 2021-11-22 65 sigfillset(&tmp_mask); e050ed271bb0008 Peter Collingbourne 2021-11-22 66 set_current_blocked(&tmp_mask); e050ed271bb0008 Peter Collingbourne 2021-11-22 67 return true; e050ed271bb0008 Peter Collingbourne 2021-11-22 68 } e050ed271bb0008 Peter Collingbourne 2021-11-22 69 e050ed271bb0008 Peter Collingbourne 2021-11-22 70 void __uaccess_buffer_post_exit_loop(void) e050ed271bb0008 Peter Collingbourne 2021-11-22 71 { e050ed271bb0008 Peter Collingbourne 2021-11-22 @72 spin_lock_irq(&current->sighand->siglock); e050ed271bb0008 Peter Collingbourne 2021-11-22 73 current->blocked = current->real_blocked; e050ed271bb0008 Peter Collingbourne 2021-11-22 74 recalc_sigpending(); e050ed271bb0008 Peter Collingbourne 2021-11-22 75 spin_unlock_irq(&current->sighand->siglock); e050ed271bb0008 Peter Collingbourne 2021-11-22 76 } e050ed271bb0008 Peter Collingbourne 2021-11-22 77 e050ed271bb0008 Peter Collingbourne 2021-11-22 78 void uaccess_buffer_cancel_log(struct task_struct *tsk) e050ed271bb0008 Peter Collingbourne 2021-11-22 79 { e050ed271bb0008 Peter Collingbourne 2021-11-22 80 struct uaccess_buffer_info *buf = &tsk->uaccess_buffer; e050ed271bb0008 Peter Collingbourne 2021-11-22 81 e050ed271bb0008 Peter Collingbourne 2021-11-22 82 if (buf->kcur) { e050ed271bb0008 Peter Collingbourne 2021-11-22 83 buf->kcur = 0; e050ed271bb0008 Peter Collingbourne 2021-11-22 84 kfree(buf->kbegin); e050ed271bb0008 Peter Collingbourne 2021-11-22 85 } e050ed271bb0008 Peter Collingbourne 2021-11-22 86 } e050ed271bb0008 Peter Collingbourne 2021-11-22 87 e050ed271bb0008 Peter Collingbourne 2021-11-22 88 void __uaccess_buffer_syscall_entry(void) e050ed271bb0008 Peter Collingbourne 2021-11-22 89 { e050ed271bb0008 Peter Collingbourne 2021-11-22 90 struct uaccess_buffer_info *buf = &current->uaccess_buffer; e050ed271bb0008 Peter Collingbourne 2021-11-22 91 struct uaccess_descriptor desc; e050ed271bb0008 Peter Collingbourne 2021-11-22 92 e050ed271bb0008 Peter Collingbourne 2021-11-22 93 if (get_user(buf->desc_ptr, buf->desc_ptr_ptr) || !buf->desc_ptr || e050ed271bb0008 Peter Collingbourne 2021-11-22 94 put_user(0, buf->desc_ptr_ptr) || e050ed271bb0008 Peter Collingbourne 2021-11-22 95 copy_from_user(&desc, buf->desc_ptr, sizeof(desc))) e050ed271bb0008 Peter Collingbourne 2021-11-22 96 return; e050ed271bb0008 Peter Collingbourne 2021-11-22 97 e050ed271bb0008 Peter Collingbourne 2021-11-22 98 if (desc.size > 1024) e050ed271bb0008 Peter Collingbourne 2021-11-22 99 desc.size = 1024; e050ed271bb0008 Peter Collingbourne 2021-11-22 100 e050ed271bb0008 Peter Collingbourne 2021-11-22 101 buf->kbegin = kmalloc_array( e050ed271bb0008 Peter Collingbourne 2021-11-22 102 desc.size, sizeof(struct uaccess_buffer_entry), GFP_KERNEL); e050ed271bb0008 Peter Collingbourne 2021-11-22 103 buf->kcur = buf->kbegin; e050ed271bb0008 Peter Collingbourne 2021-11-22 104 buf->kend = buf->kbegin + desc.size; e050ed271bb0008 Peter Collingbourne 2021-11-22 105 buf->ubegin = (struct uaccess_buffer_entry __user *)desc.addr; e050ed271bb0008 Peter Collingbourne 2021-11-22 106 } e050ed271bb0008 Peter Collingbourne 2021-11-22 107 e050ed271bb0008 Peter Collingbourne 2021-11-22 108 void __uaccess_buffer_syscall_exit(void) e050ed271bb0008 Peter Collingbourne 2021-11-22 109 { e050ed271bb0008 Peter Collingbourne 2021-11-22 110 struct uaccess_buffer_info *buf = &current->uaccess_buffer; e050ed271bb0008 Peter Collingbourne 2021-11-22 111 u64 num_entries = buf->kcur - buf->kbegin; e050ed271bb0008 Peter Collingbourne 2021-11-22 112 struct uaccess_descriptor desc; e050ed271bb0008 Peter Collingbourne 2021-11-22 113 e050ed271bb0008 Peter Collingbourne 2021-11-22 114 if (!buf->kcur) e050ed271bb0008 Peter Collingbourne 2021-11-22 115 return; e050ed271bb0008 Peter Collingbourne 2021-11-22 116 e050ed271bb0008 Peter Collingbourne 2021-11-22 @117 desc.addr = (u64)(buf->ubegin + num_entries); --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org