Re: [PATCH v2 11/12] x86/paravirt: switch functions with custom code to ALTERNATIVE

2020-11-20 Thread kernel test robot 
Hi Juergen,

I love your patch! Perhaps something to improve:

[auto build test WARNING on v5.10-rc4]
[also build test WARNING on next-20201120]
[cannot apply to tip/x86/core xen-tip/linux-next tip/x86/asm]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]

url:
https://github.com/0day-ci/linux/commits/Juergen-Gross/x86-major-paravirt-cleanup/20201120-194934
base:09162bc32c880a791c6c0668ce0745cf7958f576
config: x86_64-rhel-7.6-kselftests (attached as .config)
compiler: gcc-9 (Debian 9.3.0-15) 9.3.0
reproduce (this is a W=1 build):
# 
https://github.com/0day-ci/linux/commit/fd8d46a7a2c51313ee14c43af60ff337279384ef
git remote add linux-review https://github.com/0day-ci/linux
git fetch --no-tags linux-review 
Juergen-Gross/x86-major-paravirt-cleanup/20201120-194934
git checkout fd8d46a7a2c51313ee14c43af60ff337279384ef
# save the attached .config to linux build tree
make W=1 ARCH=x86_64 

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot 

All warnings (new ones prefixed by >>):

>> drivers/misc/lkdtm/bugs.o: warning: objtool: .altinstr_replacement+0x0: 
>> alternative modifies stack

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-...@lists.01.org


.config.gz
Description: application/gzip

[PATCH v2 11/12] x86/paravirt: switch functions with custom code to ALTERNATIVE

2020-11-20 Thread Juergen Gross 
Instead of using paravirt patching for custom code sequences use
ALTERNATIVE for the functions with custom code replacements.

Instead of patching an ud2 instruction for unpopulated vector entries
into the caller site, use a simple function just calling BUG() as a
replacement.

Signed-off-by: Juergen Gross 
---
 arch/x86/include/asm/paravirt.h   | 73 ++
 arch/x86/include/asm/paravirt_types.h |  1 -
 arch/x86/kernel/paravirt.c| 16 ++---
 arch/x86/kernel/paravirt_patch.c  | 88 ---
 4 files changed, 54 insertions(+), 124 deletions(-)

diff --git a/arch/x86/include/asm/paravirt.h b/arch/x86/include/asm/paravirt.h
index 62fbcd899539..500c64d0cfcb 100644
--- a/arch/x86/include/asm/paravirt.h
+++ b/arch/x86/include/asm/paravirt.h
@@ -108,7 +108,8 @@ static inline void write_cr0(unsigned long x)
 
 static inline unsigned long read_cr2(void)
 {
-   return PVOP_CALLEE0(unsigned long, mmu.read_cr2);
+   return PVOP_ALT_CALLEE0(unsigned long, mmu.read_cr2,
+   "mov %%cr2, %%rax;", X86_FEATURE_NOT_XENPV);
 }
 
 static inline void write_cr2(unsigned long x)
@@ -118,12 +119,14 @@ static inline void write_cr2(unsigned long x)
 
 static inline unsigned long __read_cr3(void)
 {
-   return PVOP_CALL0(unsigned long, mmu.read_cr3);
+   return PVOP_ALT_CALL0(unsigned long, mmu.read_cr3,
+ "mov %%cr3, %%rax;", X86_FEATURE_NOT_XENPV);
 }
 
 static inline void write_cr3(unsigned long x)
 {
-   PVOP_VCALL1(mmu.write_cr3, x);
+   PVOP_ALT_VCALL1(mmu.write_cr3, x,
+   "mov %%rdi, %%cr3", X86_FEATURE_NOT_XENPV);
 }
 
 static inline void __write_cr4(unsigned long x)
@@ -143,7 +146,7 @@ static inline void halt(void)
 
 static inline void wbinvd(void)
 {
-   PVOP_VCALL0(cpu.wbinvd);
+   PVOP_ALT_VCALL0(cpu.wbinvd, "wbinvd", X86_FEATURE_NOT_XENPV);
 }
 
 static inline u64 paravirt_read_msr(unsigned msr)
@@ -357,22 +360,28 @@ static inline void paravirt_release_p4d(unsigned long pfn)
 
 static inline pte_t __pte(pteval_t val)
 {
-   return (pte_t) { PVOP_CALLEE1(pteval_t, mmu.make_pte, val) };
+   return (pte_t) { PVOP_ALT_CALLEE1(pteval_t, mmu.make_pte, val,
+ "mov %%rdi, %%rax",
+ X86_FEATURE_NOT_XENPV) };
 }
 
 static inline pteval_t pte_val(pte_t pte)
 {
-   return PVOP_CALLEE1(pteval_t, mmu.pte_val, pte.pte);
+   return PVOP_ALT_CALLEE1(pteval_t, mmu.pte_val, pte.pte,
+   "mov %%rdi, %%rax", X86_FEATURE_NOT_XENPV);
 }
 
 static inline pgd_t __pgd(pgdval_t val)
 {
-   return (pgd_t) { PVOP_CALLEE1(pgdval_t, mmu.make_pgd, val) };
+   return (pgd_t) { PVOP_ALT_CALLEE1(pgdval_t, mmu.make_pgd, val,
+ "mov %%rdi, %%rax",
+ X86_FEATURE_NOT_XENPV) };
 }
 
 static inline pgdval_t pgd_val(pgd_t pgd)
 {
-   return PVOP_CALLEE1(pgdval_t, mmu.pgd_val, pgd.pgd);
+   return PVOP_ALT_CALLEE1(pgdval_t, mmu.pgd_val, pgd.pgd,
+   "mov %%rdi, %%rax", X86_FEATURE_NOT_XENPV);
 }
 
 #define  __HAVE_ARCH_PTEP_MODIFY_PROT_TRANSACTION
@@ -405,12 +414,15 @@ static inline void set_pmd(pmd_t *pmdp, pmd_t pmd)
 
 static inline pmd_t __pmd(pmdval_t val)
 {
-   return (pmd_t) { PVOP_CALLEE1(pmdval_t, mmu.make_pmd, val) };
+   return (pmd_t) { PVOP_ALT_CALLEE1(pmdval_t, mmu.make_pmd, val,
+ "mov %%rdi, %%rax",
+ X86_FEATURE_NOT_XENPV) };
 }
 
 static inline pmdval_t pmd_val(pmd_t pmd)
 {
-   return PVOP_CALLEE1(pmdval_t, mmu.pmd_val, pmd.pmd);
+   return PVOP_ALT_CALLEE1(pmdval_t, mmu.pmd_val, pmd.pmd,
+   "mov %%rdi, %%rax", X86_FEATURE_NOT_XENPV);
 }
 
 static inline void set_pud(pud_t *pudp, pud_t pud)
@@ -422,14 +434,16 @@ static inline pud_t __pud(pudval_t val)
 {
pudval_t ret;
 
-   ret = PVOP_CALLEE1(pudval_t, mmu.make_pud, val);
+   ret = PVOP_ALT_CALLEE1(pudval_t, mmu.make_pud, val,
+  "mov %%rdi, %%rax", X86_FEATURE_NOT_XENPV);
 
return (pud_t) { ret };
 }
 
 static inline pudval_t pud_val(pud_t pud)
 {
-   return PVOP_CALLEE1(pudval_t, mmu.pud_val, pud.pud);
+   return PVOP_ALT_CALLEE1(pudval_t, mmu.pud_val, pud.pud,
+   "mov %%rdi, %%rax", X86_FEATURE_NOT_XENPV);
 }
 
 static inline void pud_clear(pud_t *pudp)
@@ -448,14 +462,17 @@ static inline void set_p4d(p4d_t *p4dp, p4d_t p4d)
 
 static inline p4d_t __p4d(p4dval_t val)
 {
-   p4dval_t ret = PVOP_CALLEE1(p4dval_t, mmu.make_p4d, val);
+   p4dval_t ret = PVOP_ALT_CALLEE1(p4dval_t, mmu.make_p4d, val,
+   "mov %%rdi, %%rax",
+   X86_FEATURE_NOT_XENPV);
 
return (p4d_t) { ret };
 }
 
 static inline p