user/sven/linux.git/lib, branch v4.18.11

debugobjects: Make stack check warning more informative

2018-09-15T07:47:01Z

commit fc91a3c4c27acdca0bc13af6fbb68c35cfd519f2 upstream. While debugging an issue debugobject tracking warned about an annotation issue of an object on stack. It turned out that the issue was due to the object in concern being on a different stack which was due to another issue. Thomas suggested to print the pointers and the location of the stack for the currently running task. This helped to figure out that the object was on the wrong stack. As this is general useful information for debugging similar issues, make the error message more informative by printing the pointers. [ tglx: Massaged changelog ] Signed-off-by: Joel Fernandes (Google) Signed-off-by: Thomas Gleixner Acked-by: Waiman Long Acked-by: Yang Shi Cc: kernel-team@android.com Cc: Arnd Bergmann Cc: astrachan@google.com Link: https://lkml.kernel.org/r/20180723212531.202328-1-joel@joelfernandes.org Signed-off-by: Greg Kroah-Hartman

lib/vsprintf: Do not handle %pO[^F] as %px

2018-09-05T07:29:49Z

commit 554ec508653688c21d9b8024af73a1ffaa0164b9 upstream. This patch avoids that gcc reports the following when building with W=1: lib/vsprintf.c:1941:3: warning: this statement may fall through [-Wimplicit-fallthrough=] switch (fmt[1]) { ^~~~~~ Fixes: 7b1924a1d930eb2 ("vsprintf: add printk specifier %px") Link: http://lkml.kernel.org/r/20180806223421.11995-1-bart.vanassche@wdc.com Cc: linux-kernel@vger.kernel.org Cc: Bart Van Assche Cc: Pantelis Antoniou Cc: Joe Perches Cc: Rob Herring Cc: v4.15+ Signed-off-by: Bart Van Assche Signed-off-by: Petr Mladek Signed-off-by: Greg Kroah-Hartman

printk/nmi: Prevent deadlock when accessing the main log buffer in NMI

2018-09-05T07:29:42Z

commit 03fc7f9c99c1e7ae2925d459e8487f1a6f199f79 upstream. The commit 719f6a7040f1bdaf96 ("printk: Use the main logbuf in NMI when logbuf_lock is available") brought back the possible deadlocks in printk() and NMI. The check of logbuf_lock is done only in printk_nmi_enter() to prevent mixed output. But another CPU might take the lock later, enter NMI, and: + Both NMIs might be serialized by yet another lock, for example, the one in nmi_cpu_backtrace(). + The other CPU might get stopped in NMI, see smp_send_stop() in panic(). The only safe solution is to use trylock when storing the message into the main log-buffer. It might cause reordering when some lines go to the main lock buffer directly and others are delayed via the per-CPU buffer. It means that it is not useful in general. This patch replaces the problematic NMI deferred context with NMI direct context. It can be used to mark a code that might produce many messages in NMI and the risk of losing them is more critical than problems with eventual reordering. The context is then used when dumping trace buffers on oops. It was the primary motivation for the original fix. Also the reordering is even smaller issue there because some traces have their own time stamps. Finally, nmi_cpu_backtrace() need not longer be serialized because it will always us the per-CPU buffers again. Fixes: 719f6a7040f1bdaf96 ("printk: Use the main logbuf in NMI when logbuf_lock is available") Cc: stable@vger.kernel.org Link: http://lkml.kernel.org/r/20180627142028.11259-1-pmladek@suse.com To: Steven Rostedt Cc: Peter Zijlstra Cc: Tetsuo Handa Cc: Sergey Senozhatsky Cc: linux-kernel@vger.kernel.org Cc: stable@vger.kernel.org Acked-by: Sergey Senozhatsky Signed-off-by: Petr Mladek Signed-off-by: Greg Kroah-Hartman

ioremap: Update pgtable free interfaces with addr

2018-08-17T19:03:49Z

commit 785a19f9d1dd8a4ab2d0633be4656653bd3de1fc upstream. The following kernel panic was observed on ARM64 platform due to a stale TLB entry. 1. ioremap with 4K size, a valid pte page table is set. 2. iounmap it, its pte entry is set to 0. 3. ioremap the same address with 2M size, update its pmd entry with a new value. 4. CPU may hit an exception because the old pmd entry is still in TLB, which leads to a kernel panic. Commit b6bdb7517c3d ("mm/vmalloc: add interfaces to free unmapped page table") has addressed this panic by falling to pte mappings in the above case on ARM64. To support pmd mappings in all cases, TLB purge needs to be performed in this case on ARM64. Add a new arg, 'addr', to pud_free_pmd_page() and pmd_free_pte_page() so that TLB purge can be added later in seprate patches. [toshi.kani@hpe.com: merge changes, rewrite patch description] Fixes: 28ee90fe6048 ("x86/mm: implement free pmd/pte page interfaces") Signed-off-by: Chintan Pandya Signed-off-by: Toshi Kani Signed-off-by: Thomas Gleixner Cc: mhocko@suse.com Cc: akpm@linux-foundation.org Cc: hpa@zytor.com Cc: linux-mm@kvack.org Cc: linux-arm-kernel@lists.infradead.org Cc: Will Deacon Cc: Joerg Roedel Cc: stable@vger.kernel.org Cc: Andrew Morton Cc: Michal Hocko Cc: "H. Peter Anvin" Cc: Link: https://lkml.kernel.org/r/20180627141348.21777-3-toshi.kani@hpe.com Signed-off-by: Greg Kroah-Hartman

lib/ubsan: remove null-pointer checks

2018-08-11T03:19:58Z

With gcc-8 fsanitize=null become very noisy. GCC started to complain about things like &a->b, where 'a' is NULL pointer. There is no NULL dereference, we just calculate address to struct member. It's technically undefined behavior so UBSAN is correct to report it. But as long as there is no real NULL-dereference, I think, we should be fine. -fno-delete-null-pointer-checks compiler flag should protect us from any consequences. So let's just no use -fsanitize=null as it's not useful for us. If there is a real NULL-deref we will see crash. Even if userspace mapped something at NULL (root can do this), with things like SMAP should catch the issue. Link: http://lkml.kernel.org/r/20180802153209.813-1-aryabinin@virtuozzo.com Signed-off-by: Andrey Ryabinin Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

kasan: only select SLUB_DEBUG with SYSFS=y

2018-07-27T02:38:03Z

Building with KASAN and SLUB but without sysfs now results in a build-time error: WARNING: unmet direct dependencies detected for SLUB_DEBUG Depends on [n]: SLUB [=y] && SYSFS [=n] Selected by [y]: - KASAN [=y] && HAVE_ARCH_KASAN [=y] && (SLUB [=y] || SLAB [=n] && !DEBUG_SLAB [=n]) && SLUB [=y] mm/slub.c:4565:12: error: 'list_locations' defined but not used [-Werror=unused-function] static int list_locations(struct kmem_cache *s, char *buf, ^~~~~~~~~~~~~~ mm/slub.c:4406:13: error: 'validate_slab_cache' defined but not used [-Werror=unused-function] static long validate_slab_cache(struct kmem_cache *s) This disallows that broken configuration in Kconfig. Link: http://lkml.kernel.org/r/20180709154019.1693026-1-arnd@arndb.de Fixes: dd275caf4a0d ("kasan: depend on CONFIG_SLUB_DEBUG") Signed-off-by: Arnd Bergmann Cc: "Jason A. Donenfeld" Cc: Arnd Bergmann Cc: Shakeel Butt Cc: Andrey Ryabinin Cc: Christoph Lameter Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

Merge branch 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2018-07-21T23:52:08Z

Pull core kernel fixes from Ingo Molnar: "This is mostly the copy_to_user_mcsafe() related fixes from Dan Williams, and an ORC fix for Clang" * 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/asm/memcpy_mcsafe: Fix copy_to_user_mcsafe() exception handling lib/iov_iter: Fix pipe handling in _copy_to_iter_mcsafe() lib/iov_iter: Document _copy_to_iter_flushcache() lib/iov_iter: Document _copy_to_iter_mcsafe() objtool: Use '.strtab' if '.shstrtab' doesn't exist, to support ORC tables on Clang

lib/rhashtable: consider param->min_size when setting initial table size

2018-07-18T20:27:43Z

rhashtable_init() currently does not take into account the user-passed min_size parameter unless param->nelem_hint is set as well. As such, the default size (number of buckets) will always be HASH_DEFAULT_SIZE even if the smallest allowed size is larger than that. Remediate this by unconditionally calling into rounded_hashtable_size() and handling things accordingly. Signed-off-by: Davidlohr Bueso Acked-by: Herbert Xu Signed-off-by: David S. Miller

lib/iov_iter: Fix pipe handling in _copy_to_iter_mcsafe()

2018-07-15T22:05:05Z

By mistake the ITER_PIPE early-exit / warning from copy_from_iter() was cargo-culted in _copy_to_iter_mcsafe() rather than a machine-check-safe version of copy_to_iter_pipe(). Implement copy_pipe_to_iter_mcsafe() being careful to return the indication of short copies due to a CPU exception. Without this regression-fix all splice reads to dax-mode files fail. Reported-by: Ross Zwisler Tested-by: Ross Zwisler Signed-off-by: Dan Williams Acked-by: Al Viro Cc: Andrew Morton Cc: Andy Lutomirski Cc: Borislav Petkov Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: Tony Luck Fixes: 8780356ef630 ("x86/asm/memcpy_mcsafe: Define copy_to_iter_mcsafe()") Link: http://lkml.kernel.org/r/153108277278.37979.3327916996902264102.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Ingo Molnar

lib/iov_iter: Document _copy_to_iter_flushcache()

2018-07-15T22:05:05Z

Add some theory of operation documentation to _copy_to_iter_flushcache(). Reported-by: Al Viro Signed-off-by: Dan Williams Cc: Andrew Morton Cc: Andy Lutomirski Cc: Borislav Petkov Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: Tony Luck Link: http://lkml.kernel.org/r/153108276767.37979.9462477994086841699.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Ingo Molnar