Commit-ID: 0e664eee65337082be49fbbd2ee24aa0d111d0f2 Gitweb: https://git.kernel.org/tip/0e664eee65337082be49fbbd2ee24aa0d111d0f2 Author: Joerg Roedel <jroe...@suse.de> AuthorDate: Wed, 25 Jul 2018 17:48:02 +0200 Committer: Thomas Gleixner <t...@linutronix.de> CommitDate: Mon, 30 Jul 2018 13:53:48 +0200
Revert "perf/core: Make sure the ring-buffer is mapped in all page-tables" This reverts commit 77754cfa09a6c528c38cbca9ee4cc4f7cf6ad6f2. The patch was necessary to silence a WARN_ON_ONCE(in_nmi()) that triggered in the vmalloc_fault() function when PTI was enabled on x86-32. Faulting in an NMI handler turned out to be safe and the warning in vmalloc_fault() is gone now. So the above patch can be reverted. Signed-off-by: Joerg Roedel <jroe...@suse.de> Signed-off-by: Thomas Gleixner <t...@linutronix.de> Tested-by: David H. Gutteridge <dhgutteri...@sympatico.ca> Cc: "H . Peter Anvin" <h...@zytor.com> Cc: linux...@kvack.org Cc: Linus Torvalds <torva...@linux-foundation.org> Cc: Andy Lutomirski <l...@kernel.org> Cc: Dave Hansen <dave.han...@intel.com> Cc: Josh Poimboeuf <jpoim...@redhat.com> Cc: Juergen Gross <jgr...@suse.com> Cc: Peter Zijlstra <pet...@infradead.org> Cc: Borislav Petkov <b...@alien8.de> Cc: Jiri Kosina <jkos...@suse.cz> Cc: Boris Ostrovsky <boris.ostrov...@oracle.com> Cc: Brian Gerst <brge...@gmail.com> Cc: David Laight <david.lai...@aculab.com> Cc: Denys Vlasenko <dvlas...@redhat.com> Cc: Eduardo Valentin <edu...@amazon.com> Cc: Greg KH <gre...@linuxfoundation.org> Cc: Will Deacon <will.dea...@arm.com> Cc: aligu...@amazon.com Cc: daniel.gr...@iaik.tugraz.at Cc: hu...@google.com Cc: keesc...@google.com Cc: Andrea Arcangeli <aarca...@redhat.com> Cc: Waiman Long <ll...@redhat.com> Cc: Pavel Machek <pa...@ucw.cz> Cc: Arnaldo Carvalho de Melo <a...@kernel.org> Cc: Alexander Shishkin <alexander.shish...@linux.intel.com> Cc: Jiri Olsa <jo...@redhat.com> Cc: Namhyung Kim <namhy...@kernel.org> Cc: j...@8bytes.org Link: https://lkml.kernel.org/r/1532533683-5988-3-git-send-email-j...@8bytes.org --- kernel/events/ring_buffer.c | 16 ---------------- 1 file changed, 16 deletions(-) diff --git a/kernel/events/ring_buffer.c b/kernel/events/ring_buffer.c index df2d8cf0072c..5d3cf407e374 100644 --- a/kernel/events/ring_buffer.c +++ b/kernel/events/ring_buffer.c @@ -814,13 +814,6 @@ static void rb_free_work(struct work_struct *work) vfree(base); kfree(rb); - - /* - * FIXME: PAE workaround for vmalloc_fault(): Make sure buffer is - * unmapped in all page-tables. - */ - if (IS_ENABLED(CONFIG_X86_PAE)) - vmalloc_sync_all(); } void rb_free(struct ring_buffer *rb) @@ -847,15 +840,6 @@ struct ring_buffer *rb_alloc(int nr_pages, long watermark, int cpu, int flags) if (!all_buf) goto fail_all_buf; - /* - * FIXME: PAE workaround for vmalloc_fault(): The buffer is - * accessed in NMI handlers, make sure it is mapped in all - * page-tables in the system so that we don't fault on the range in - * an NMI handler. - */ - if (IS_ENABLED(CONFIG_X86_PAE)) - vmalloc_sync_all(); - rb->user_page = all_buf; rb->data_pages[0] = all_buf + PAGE_SIZE; if (nr_pages) {
