From mboxrd@z Thu Jan 1 00:00:00 1970 From: Rick Edgecombe Subject: [PATCH v3 18/20] x86/ftrace: Use vmalloc special flag Date: Thu, 21 Feb 2019 15:44:49 -0800 Message-Id: <20190221234451.17632-19-rick.p.edgecombe@intel.com> In-Reply-To: <20190221234451.17632-1-rick.p.edgecombe@intel.com> References: <20190221234451.17632-1-rick.p.edgecombe@intel.com> To: Andy Lutomirski , Ingo Molnar Cc: linux-kernel@vger.kernel.org, x86@kernel.org, hpa@zytor.com, Thomas Gleixner , Borislav Petkov , Nadav Amit , Dave Hansen , Peter Zijlstra , linux_dti@icloud.com, linux-integrity@vger.kernel.org, linux-security-module@vger.kernel.org, akpm@linux-foundation.org, kernel-hardening@lists.openwall.com, linux-mm@kvack.org, will.deacon@arm.com, ard.biesheuvel@linaro.org, kristen@linux.intel.com, deneen.t.dock@intel.com, Rick Edgecombe , Steven Rostedt List-ID: Use new flag VM_FLUSH_RESET_PERMS for handling freeing of special permissioned memory in vmalloc and remove places where memory was set NX and RW before freeing which is no longer needed. Cc: Steven Rostedt Acked-by: Steven Rostedt (VMware) Signed-off-by: Rick Edgecombe --- arch/x86/kernel/ftrace.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) diff --git a/arch/x86/kernel/ftrace.c b/arch/x86/kernel/ftrace.c index 13c8249b197f..93efe3955333 100644 --- a/arch/x86/kernel/ftrace.c +++ b/arch/x86/kernel/ftrace.c @@ -692,10 +692,6 @@ static inline void *alloc_tramp(unsigned long size) } static inline void tramp_free(void *tramp, int size) { - int npages = PAGE_ALIGN(size) >> PAGE_SHIFT; - - set_memory_nx((unsigned long)tramp, npages); - set_memory_rw((unsigned long)tramp, npages); module_memfree(tramp); } #else @@ -820,6 +816,8 @@ create_trampoline(struct ftrace_ops *ops, unsigned int *tramp_size) /* ALLOC_TRAMP flags lets us know we created it */ ops->flags |= FTRACE_OPS_FL_ALLOC_TRAMP; + set_vm_flush_reset_perms(trampoline); + /* * Module allocation needs to be completed by making the page * executable. The page is still writable, which is a security hazard, -- 2.17.1