Re: [PATCH 6.6.y] x86/paravirt: Move halt paravirt calls under CONFIG_PARAVIRT

[Sasha Levin <sashal@kernel.org>]

[ Sasha's backport helper bot ]

Hi,

Summary of potential issues:
⚠️ Found matching upstream commit but patch is missing proper reference to it

Found matching upstream commit: 22cc5ca5de52bbfc36a7d4a55323f91fb4492264

WARNING: Author mismatch between patch and found commit:
Backport author: Vishal Annapurve<vannapurve@google.com>
Commit author: Kirill A. Shutemov<kirill.shutemov@linux.intel.com>

Status in newer kernel trees:
6.14.y | Present (different SHA1: 263850bf7db9)
6.13.y | Not found
6.12.y | Not found

Note: The patch differs from the upstream commit:
---
1:  22cc5ca5de52b ! 1:  1a8f60a371a74 x86/paravirt: Move halt paravirt calls under CONFIG_PARAVIRT
    @@ Commit message
         Cc: Josh Poimboeuf <jpoimboe@redhat.com>
         Cc: stable@kernel.org
         Link: https://lore.kernel.org/r/20250228014416.3925664-2-vannapurve@google.com
    +    (cherry picked from commit 22cc5ca5de52bbfc36a7d4a55323f91fb4492264)
     
      ## arch/x86/include/asm/irqflags.h ##
    -@@ arch/x86/include/asm/irqflags.h: static __always_inline void native_local_irq_restore(unsigned long flags)
    +@@ arch/x86/include/asm/irqflags.h: static __always_inline void native_halt(void)
      
      #endif
      
    @@ arch/x86/include/asm/paravirt.h: static inline void __write_cr4(unsigned long x)
     -	PVOP_VCALL0(irq.halt);
     -}
     -
    - static inline u64 paravirt_read_msr(unsigned msr)
    - {
    - 	return PVOP_CALL1(u64, cpu.read_msr, msr);
    + extern noinstr void pv_native_wbinvd(void);
    + 
    + static __always_inline void wbinvd(void)
     
      ## arch/x86/include/asm/paravirt_types.h ##
     @@ arch/x86/include/asm/paravirt_types.h: struct pv_irq_ops {
    @@ arch/x86/include/asm/paravirt_types.h: struct pv_irq_ops {
      struct pv_mmu_ops {
     
      ## arch/x86/kernel/paravirt.c ##
    -@@ arch/x86/kernel/paravirt.c: void paravirt_set_sched_clock(u64 (*func)(void))
    - 	static_call_update(pv_sched_clock, func);
    +@@ arch/x86/kernel/paravirt.c: int paravirt_disable_iospace(void)
    + 	return request_resource(&ioport_resource, &reserve_ioports);
      }
      
     +static noinstr void pv_native_safe_halt(void)
    @@ arch/x86/kernel/paravirt.c: void paravirt_set_sched_clock(u64 (*func)(void))
      #ifdef CONFIG_PARAVIRT_XXL
      static noinstr void pv_native_write_cr2(unsigned long val)
      {
    -@@ arch/x86/kernel/paravirt.c: static noinstr void pv_native_set_debugreg(int regno, unsigned long val)
    +@@ arch/x86/kernel/paravirt.c: noinstr void pv_native_wbinvd(void)
      {
    - 	native_set_debugreg(regno, val);
    + 	native_wbinvd();
      }
     -
     -static noinstr void pv_native_safe_halt(void)
---

Results of testing on various branches:

| Branch                    | Patch Apply | Build Test |
|---------------------------|-------------|------------|
| stable/linux-6.6.y        |  Success    |  Success   |