From mboxrd@z Thu Jan 1 00:00:00 1970 From: Josh Poimboeuf Subject: [PATCH 00/13] x86/paravirt: Make pv ops code generation more closely match reality Date: Wed, 4 Oct 2017 10:58:21 -0500 Message-ID: Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: virtualization-bounces@lists.linux-foundation.org Errors-To: virtualization-bounces@lists.linux-foundation.org To: x86@kernel.org Cc: Juergen Gross , Rusty Russell , xen-devel@lists.xenproject.org, Peter Zijlstra , Jiri Slaby , Boris Ostrovsky , Mike Galbraith , linux-kernel@vger.kernel.org, Sasha Levin , Chris Wright , Thomas Gleixner , Andy Lutomirski , "H. Peter Anvin" , Borislav Petkov , live-patching@vger.kernel.org, Alok Kataria , virtualization@lists.linux-foundation.org, Linus Torvalds , Ingo Molnar List-Id: virtualization@lists.linuxfoundation.org This changes the pv ops code generation to more closely match reality. For example, instead of: callq *0xffffffff81e3a400 (pv_irq_ops.save_fl) vmlinux will now show: pushfq pop %rax nop nop nop nop nop which is what the runtime version of the code will show in most cases. This idea was suggested by Andy Lutomirski. The benefits are: - For the most common runtime cases (everything except Xen and vSMP), vmlinux disassembly now matches what the actual runtime code looks like. This improves debuggability and kernel developer sanity (a precious resource). - It fixes a KASAN warning in the ORC unwinder due to objtool not understanding the .parainstructions stuff. - It's hopefully a first step in simplifying paravirt patching by getting rid of .parainstructions, pv ops, and apply_paravirt() completely. (I think Xen can be changed to set CPU feature bits to specify which ops it needs during early boot, then those ops can be patched in using early alternatives.) For more details, see the commit log in patch 11/13. Josh Poimboeuf (13): x86/paravirt: remove wbinvd() paravirt interface x86/paravirt: Fix output constraint macro names x86/paravirt: Convert native patch assembly code strings to macros x86/paravirt: Convert DEF_NATIVE macro to GCC extended asm syntax x86/paravirt: Move paravirt asm macros to paravirt-asm.h x86/paravirt: Clean up paravirt-asm.h x86/paravirt: Simplify ____PVOP_CALL() x86/paravirt: Clean up paravirt_types.h x86/asm: Convert ALTERNATIVE*() assembler macros to preprocessor macros x86/alternative: Support indirect call replacement x86/paravirt: Add paravirt alternatives infrastructure objtool: Add support for new .pv_altinstructions section x86/paravirt: Convert natively patched pv ops to use paravirt alternatives arch/x86/entry/entry_32.S | 13 +- arch/x86/entry/entry_64.S | 12 +- arch/x86/entry/entry_64_compat.S | 9 +- arch/x86/entry/vdso/vdso32/system_call.S | 10 +- arch/x86/include/asm/alternative-asm.h | 71 ++++----- arch/x86/include/asm/alternative.h | 12 +- arch/x86/include/asm/cpufeatures.h | 1 + arch/x86/include/asm/paravirt-asm.h | 142 ++++++++++++++++++ arch/x86/include/asm/paravirt.h | 174 ++++------------------ arch/x86/include/asm/paravirt_types.h | 243 ++++++++++++++++++++----------- arch/x86/include/asm/smap.h | 4 +- arch/x86/include/asm/special_insns.h | 31 +++- arch/x86/kernel/alternative.c | 35 ++++- arch/x86/kernel/cpu/hypervisor.c | 2 + arch/x86/kernel/head_64.S | 2 +- arch/x86/kernel/module.c | 11 +- arch/x86/kernel/paravirt.c | 1 - arch/x86/kernel/paravirt_patch_32.c | 21 +-- arch/x86/kernel/paravirt_patch_64.c | 31 ++-- arch/x86/kernel/vmlinux.lds.S | 6 + arch/x86/lib/copy_page_64.S | 2 +- arch/x86/lib/memcpy_64.S | 4 +- arch/x86/lib/memmove_64.S | 3 +- arch/x86/lib/memset_64.S | 4 +- arch/x86/xen/enlighten_pv.c | 3 +- tools/objtool/special.c | 10 ++ 26 files changed, 516 insertions(+), 341 deletions(-) create mode 100644 arch/x86/include/asm/paravirt-asm.h -- 2.13.6