From: Joerg Roedel <[email protected]> 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 <[email protected]> --- 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 df2d8cf..5d3cf40 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) { -- 2.7.4
