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From: David Hildenbrand <david@redhat.com>
To: Richard Henderson <richard.henderson@linaro.org>, qemu-devel@nongnu.org
Cc: pbonzini@redhat.com, alex.bennee@linaro.org, stefanha@redhat.com
Subject: Re: [PATCH v3 10/20] cputlb: Introduce TLB_BSWAP
Date: Mon, 23 Sep 2019 10:33:00 +0200	[thread overview]
Message-ID: <9738c9e7-49fd-45e3-c6cc-1e469b5b20e1@redhat.com> (raw)
In-Reply-To: <20190922035458.14879-11-richard.henderson@linaro.org>

On 22.09.19 05:54, Richard Henderson wrote:
> Handle bswap on ram directly in load/store_helper.  This fixes a
> bug with the previous implementation in that one cannot use the
> I/O path for RAM.
> 
> Fixes: a26fc6f5152b47f1
> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
> ---
>  include/exec/cpu-all.h |   4 +-
>  accel/tcg/cputlb.c     | 108 +++++++++++++++++++++--------------------
>  2 files changed, 59 insertions(+), 53 deletions(-)
> 
> diff --git a/include/exec/cpu-all.h b/include/exec/cpu-all.h
> index 2db73c7a27..1ebd1b59ab 100644
> --- a/include/exec/cpu-all.h
> +++ b/include/exec/cpu-all.h
> @@ -346,12 +346,14 @@ CPUArchState *cpu_copy(CPUArchState *env);
>  #define TLB_MMIO            (1 << (TARGET_PAGE_BITS_MIN - 3))
>  /* Set if TLB entry contains a watchpoint.  */
>  #define TLB_WATCHPOINT      (1 << (TARGET_PAGE_BITS_MIN - 4))
> +/* Set if TLB entry requires byte swap.  */
> +#define TLB_BSWAP           (1 << (TARGET_PAGE_BITS_MIN - 5))
>  
>  /* Use this mask to check interception with an alignment mask
>   * in a TCG backend.
>   */
>  #define TLB_FLAGS_MASK \
> -    (TLB_INVALID_MASK | TLB_NOTDIRTY | TLB_MMIO | TLB_WATCHPOINT)
> +    (TLB_INVALID_MASK | TLB_NOTDIRTY | TLB_MMIO | TLB_WATCHPOINT | TLB_BSWAP)
>  
>  /**
>   * tlb_hit_page: return true if page aligned @addr is a hit against the
> diff --git a/accel/tcg/cputlb.c b/accel/tcg/cputlb.c
> index b4a63d3928..cb603917a2 100644
> --- a/accel/tcg/cputlb.c
> +++ b/accel/tcg/cputlb.c
> @@ -737,8 +737,7 @@ void tlb_set_page_with_attrs(CPUState *cpu, target_ulong vaddr,
>          address |= TLB_INVALID_MASK;
>      }
>      if (attrs.byte_swap) {
> -        /* Force the access through the I/O slow path.  */
> -        address |= TLB_MMIO;
> +        address |= TLB_BSWAP;
>      }
>      if (!memory_region_is_ram(section->mr) &&
>          !memory_region_is_romd(section->mr)) {
> @@ -901,10 +900,6 @@ static uint64_t io_readx(CPUArchState *env, CPUIOTLBEntry *iotlbentry,
>      bool locked = false;
>      MemTxResult r;
>  
> -    if (iotlbentry->attrs.byte_swap) {
> -        op ^= MO_BSWAP;
> -    }
> -
>      section = iotlb_to_section(cpu, iotlbentry->addr, iotlbentry->attrs);
>      mr = section->mr;
>      mr_offset = (iotlbentry->addr & TARGET_PAGE_MASK) + addr;
> @@ -947,10 +942,6 @@ static void io_writex(CPUArchState *env, CPUIOTLBEntry *iotlbentry,
>      bool locked = false;
>      MemTxResult r;
>  
> -    if (iotlbentry->attrs.byte_swap) {
> -        op ^= MO_BSWAP;
> -    }
> -
>      section = iotlb_to_section(cpu, iotlbentry->addr, iotlbentry->attrs);
>      mr = section->mr;
>      mr_offset = (iotlbentry->addr & TARGET_PAGE_MASK) + addr;
> @@ -1133,8 +1124,8 @@ void *probe_access(CPUArchState *env, target_ulong addr, int size,
>                               wp_access, retaddr);
>      }
>  
> -    if (tlb_addr & (TLB_NOTDIRTY | TLB_MMIO)) {
> -        /* I/O access */
> +    /* Reject I/O access, or other required slow-path.  */
> +    if (tlb_addr & (TLB_NOTDIRTY | TLB_MMIO | TLB_BSWAP)) {
>          return NULL;
>      }
>  
> @@ -1311,7 +1302,8 @@ static inline uint64_t wrap_ldul_le(const void *haddr)
>  static inline uint64_t QEMU_ALWAYS_INLINE
>  load_helper(CPUArchState *env, target_ulong addr, TCGMemOpIdx oi,
>              uintptr_t retaddr, MemOp op, bool code_read,
> -            FullLoadHelper *full_load, LoadHelper *direct)
> +            FullLoadHelper *full_load, LoadHelper *direct,
> +            LoadHelper *direct_swap)
>  {
>      uintptr_t mmu_idx = get_mmuidx(oi);
>      uintptr_t index = tlb_index(env, mmu_idx, addr);
> @@ -1361,17 +1353,21 @@ load_helper(CPUArchState *env, target_ulong addr, TCGMemOpIdx oi,
>              /* On watchpoint hit, this will longjmp out.  */
>              cpu_check_watchpoint(env_cpu(env), addr, size,
>                                   iotlbentry->attrs, BP_MEM_READ, retaddr);
> -
> -            /* The backing page may or may not require I/O.  */
> -            tlb_addr &= ~TLB_WATCHPOINT;
> -            if ((tlb_addr & ~TARGET_PAGE_MASK) == 0) {
> -                goto do_aligned_access;
> -            }
>          }
>  
>          /* Handle I/O access.  */
> -        return io_readx(env, iotlbentry, mmu_idx, addr,
> -                        retaddr, access_type, op);
> +        if (likely(tlb_addr & TLB_MMIO)) {
> +            return io_readx(env, iotlbentry, mmu_idx, addr,
> +                            retaddr, access_type,
> +                            op ^ (tlb_addr & TLB_BSWAP ? MO_BSWAP : 0));
> +        }
> +
> +        haddr = (void *)((uintptr_t)addr + entry->addend);
> +
> +        if (unlikely(tlb_addr & TLB_BSWAP)) {
> +            return direct_swap(haddr);
> +        }
> +        return direct(haddr);
>      }
>  
>      /* Handle slow unaligned access (it spans two pages or IO).  */
> @@ -1398,7 +1394,6 @@ load_helper(CPUArchState *env, target_ulong addr, TCGMemOpIdx oi,
>          return res & MAKE_64BIT_MASK(0, size * 8);
>      }
>  
> - do_aligned_access:
>      haddr = (void *)((uintptr_t)addr + entry->addend);
>      return direct(haddr);
>  }
> @@ -1417,7 +1412,7 @@ static uint64_t full_ldub_mmu(CPUArchState *env, target_ulong addr,
>                                TCGMemOpIdx oi, uintptr_t retaddr)
>  {
>      return load_helper(env, addr, oi, retaddr, MO_UB, false,
> -                       full_ldub_mmu, wrap_ldub);
> +                       full_ldub_mmu, wrap_ldub, wrap_ldub);
>  }
>  
>  tcg_target_ulong helper_ret_ldub_mmu(CPUArchState *env, target_ulong addr,
> @@ -1430,7 +1425,7 @@ static uint64_t full_le_lduw_mmu(CPUArchState *env, target_ulong addr,
>                                   TCGMemOpIdx oi, uintptr_t retaddr)
>  {
>      return load_helper(env, addr, oi, retaddr, MO_LEUW, false,
> -                       full_le_lduw_mmu, wrap_lduw_le);
> +                       full_le_lduw_mmu, wrap_lduw_le, wrap_lduw_be);
>  }
>  
>  tcg_target_ulong helper_le_lduw_mmu(CPUArchState *env, target_ulong addr,
> @@ -1443,7 +1438,7 @@ static uint64_t full_be_lduw_mmu(CPUArchState *env, target_ulong addr,
>                                   TCGMemOpIdx oi, uintptr_t retaddr)
>  {
>      return load_helper(env, addr, oi, retaddr, MO_BEUW, false,
> -                       full_be_lduw_mmu, wrap_lduw_be);
> +                       full_be_lduw_mmu, wrap_lduw_be, wrap_lduw_le);
>  }
>  
>  tcg_target_ulong helper_be_lduw_mmu(CPUArchState *env, target_ulong addr,
> @@ -1456,7 +1451,7 @@ static uint64_t full_le_ldul_mmu(CPUArchState *env, target_ulong addr,
>                                   TCGMemOpIdx oi, uintptr_t retaddr)
>  {
>      return load_helper(env, addr, oi, retaddr, MO_LEUL, false,
> -                       full_le_ldul_mmu, wrap_ldul_le);
> +                       full_le_ldul_mmu, wrap_ldul_le, wrap_ldul_be);
>  }
>  
>  tcg_target_ulong helper_le_ldul_mmu(CPUArchState *env, target_ulong addr,
> @@ -1469,7 +1464,7 @@ static uint64_t full_be_ldul_mmu(CPUArchState *env, target_ulong addr,
>                                   TCGMemOpIdx oi, uintptr_t retaddr)
>  {
>      return load_helper(env, addr, oi, retaddr, MO_BEUL, false,
> -                       full_be_ldul_mmu, wrap_ldul_be);
> +                       full_be_ldul_mmu, wrap_ldul_be, wrap_ldul_le);
>  }
>  
>  tcg_target_ulong helper_be_ldul_mmu(CPUArchState *env, target_ulong addr,
> @@ -1482,14 +1477,14 @@ uint64_t helper_le_ldq_mmu(CPUArchState *env, target_ulong addr,
>                             TCGMemOpIdx oi, uintptr_t retaddr)
>  {
>      return load_helper(env, addr, oi, retaddr, MO_LEQ, false,
> -                       helper_le_ldq_mmu, ldq_le_p);
> +                       helper_le_ldq_mmu, ldq_le_p, ldq_be_p);
>  }
>  
>  uint64_t helper_be_ldq_mmu(CPUArchState *env, target_ulong addr,
>                             TCGMemOpIdx oi, uintptr_t retaddr)
>  {
>      return load_helper(env, addr, oi, retaddr, MO_BEQ, false,
> -                       helper_be_ldq_mmu, ldq_be_p);
> +                       helper_be_ldq_mmu, ldq_be_p, ldq_le_p);
>  }
>  
>  /*
> @@ -1563,7 +1558,7 @@ static inline void wrap_stl_le(void *haddr, uint64_t val)
>  static inline void QEMU_ALWAYS_INLINE
>  store_helper(CPUArchState *env, target_ulong addr, uint64_t val,
>               TCGMemOpIdx oi, uintptr_t retaddr, MemOp op,
> -             StoreHelper *direct)
> +             StoreHelper *direct, StoreHelper *direct_swap)
>  {
>      uintptr_t mmu_idx = get_mmuidx(oi);
>      uintptr_t index = tlb_index(env, mmu_idx, addr);
> @@ -1608,16 +1603,22 @@ store_helper(CPUArchState *env, target_ulong addr, uint64_t val,
>              /* On watchpoint hit, this will longjmp out.  */
>              cpu_check_watchpoint(env_cpu(env), addr, size,
>                                   iotlbentry->attrs, BP_MEM_WRITE, retaddr);
> -
> -            /* The backing page may or may not require I/O.  */
> -            tlb_addr &= ~TLB_WATCHPOINT;
> -            if ((tlb_addr & ~TARGET_PAGE_MASK) == 0) {
> -                goto do_aligned_access;
> -            }
>          }
>  
>          /* Handle I/O access.  */
> -        io_writex(env, iotlbentry, mmu_idx, val, addr, retaddr, op);
> +        if (likely(tlb_addr & (TLB_MMIO | TLB_NOTDIRTY))) {
> +            io_writex(env, iotlbentry, mmu_idx, val, addr, retaddr,
> +                      op ^ (tlb_addr & TLB_BSWAP ? MO_BSWAP : 0));
> +            return;
> +        }
> +
> +        haddr = (void *)((uintptr_t)addr + entry->addend);
> +
> +        if (unlikely(tlb_addr & TLB_BSWAP)) {
> +            direct_swap(haddr, val);
> +        } else {
> +            direct(haddr, val);
> +        }
>          return;
>      }
>  
> @@ -1686,7 +1687,6 @@ store_helper(CPUArchState *env, target_ulong addr, uint64_t val,
>          return;
>      }
>  
> - do_aligned_access:
>      haddr = (void *)((uintptr_t)addr + entry->addend);
>      direct(haddr, val);
>  }
> @@ -1694,43 +1694,47 @@ store_helper(CPUArchState *env, target_ulong addr, uint64_t val,
>  void helper_ret_stb_mmu(CPUArchState *env, target_ulong addr, uint8_t val,
>                          TCGMemOpIdx oi, uintptr_t retaddr)
>  {
> -    store_helper(env, addr, val, oi, retaddr, MO_UB, wrap_stb);
> +    store_helper(env, addr, val, oi, retaddr, MO_UB, wrap_stb, wrap_stb);
>  }
>  
>  void helper_le_stw_mmu(CPUArchState *env, target_ulong addr, uint16_t val,
>                         TCGMemOpIdx oi, uintptr_t retaddr)
>  {
> -    store_helper(env, addr, val, oi, retaddr, MO_LEUW, wrap_stw_le);
> +    store_helper(env, addr, val, oi, retaddr, MO_LEUW,
> +                 wrap_stw_le, wrap_stw_be);
>  }
>  
>  void helper_be_stw_mmu(CPUArchState *env, target_ulong addr, uint16_t val,
>                         TCGMemOpIdx oi, uintptr_t retaddr)
>  {
> -    store_helper(env, addr, val, oi, retaddr, MO_BEUW, wrap_stw_be);
> +    store_helper(env, addr, val, oi, retaddr, MO_BEUW,
> +                 wrap_stw_be, wrap_stw_le);
>  }
>  
>  void helper_le_stl_mmu(CPUArchState *env, target_ulong addr, uint32_t val,
>                         TCGMemOpIdx oi, uintptr_t retaddr)
>  {
> -    store_helper(env, addr, val, oi, retaddr, MO_LEUL, wrap_stl_le);
> +    store_helper(env, addr, val, oi, retaddr, MO_LEUL,
> +                 wrap_stl_le, wrap_stl_be);
>  }
>  
>  void helper_be_stl_mmu(CPUArchState *env, target_ulong addr, uint32_t val,
>                         TCGMemOpIdx oi, uintptr_t retaddr)
>  {
> -    store_helper(env, addr, val, oi, retaddr, MO_BEUL, wrap_stl_be);
> +    store_helper(env, addr, val, oi, retaddr, MO_BEUL,
> +                 wrap_stl_be, wrap_stl_le);
>  }
>  
>  void helper_le_stq_mmu(CPUArchState *env, target_ulong addr, uint64_t val,
>                         TCGMemOpIdx oi, uintptr_t retaddr)
>  {
> -    store_helper(env, addr, val, oi, retaddr, MO_LEQ, stq_le_p);
> +    store_helper(env, addr, val, oi, retaddr, MO_LEQ, stq_le_p, stq_be_p);
>  }
>  
>  void helper_be_stq_mmu(CPUArchState *env, target_ulong addr, uint64_t val,
>                         TCGMemOpIdx oi, uintptr_t retaddr)
>  {
> -    store_helper(env, addr, val, oi, retaddr, MO_BEQ, stq_be_p);
> +    store_helper(env, addr, val, oi, retaddr, MO_BEQ, stq_be_p, stq_le_p);
>  }
>  
>  /* First set of helpers allows passing in of OI and RETADDR.  This makes
> @@ -1796,7 +1800,7 @@ static uint64_t full_ldub_cmmu(CPUArchState *env, target_ulong addr,
>                                 TCGMemOpIdx oi, uintptr_t retaddr)
>  {
>      return load_helper(env, addr, oi, retaddr, MO_8, true,
> -                       full_ldub_cmmu, wrap_ldub);
> +                       full_ldub_cmmu, wrap_ldub, wrap_ldub);
>  }
>  
>  uint8_t helper_ret_ldb_cmmu(CPUArchState *env, target_ulong addr,
> @@ -1809,7 +1813,7 @@ static uint64_t full_le_lduw_cmmu(CPUArchState *env, target_ulong addr,
>                                    TCGMemOpIdx oi, uintptr_t retaddr)
>  {
>      return load_helper(env, addr, oi, retaddr, MO_LEUW, true,
> -                       full_le_lduw_cmmu, wrap_lduw_le);
> +                       full_le_lduw_cmmu, wrap_lduw_le, wrap_lduw_be);
>  }
>  
>  uint16_t helper_le_ldw_cmmu(CPUArchState *env, target_ulong addr,
> @@ -1822,7 +1826,7 @@ static uint64_t full_be_lduw_cmmu(CPUArchState *env, target_ulong addr,
>                                    TCGMemOpIdx oi, uintptr_t retaddr)
>  {
>      return load_helper(env, addr, oi, retaddr, MO_BEUW, true,
> -                       full_be_lduw_cmmu, wrap_lduw_be);
> +                       full_be_lduw_cmmu, wrap_lduw_be, wrap_lduw_le);
>  }
>  
>  uint16_t helper_be_ldw_cmmu(CPUArchState *env, target_ulong addr,
> @@ -1835,7 +1839,7 @@ static uint64_t full_le_ldul_cmmu(CPUArchState *env, target_ulong addr,
>                                    TCGMemOpIdx oi, uintptr_t retaddr)
>  {
>      return load_helper(env, addr, oi, retaddr, MO_LEUL, true,
> -                       full_le_ldul_cmmu, wrap_ldul_le);
> +                       full_le_ldul_cmmu, wrap_ldul_le, wrap_ldul_be);
>  }
>  
>  uint32_t helper_le_ldl_cmmu(CPUArchState *env, target_ulong addr,
> @@ -1848,7 +1852,7 @@ static uint64_t full_be_ldul_cmmu(CPUArchState *env, target_ulong addr,
>                                    TCGMemOpIdx oi, uintptr_t retaddr)
>  {
>      return load_helper(env, addr, oi, retaddr, MO_BEUL, true,
> -                       full_be_ldul_cmmu, wrap_ldul_be);
> +                       full_be_ldul_cmmu, wrap_ldul_be, wrap_ldul_le);
>  }
>  
>  uint32_t helper_be_ldl_cmmu(CPUArchState *env, target_ulong addr,
> @@ -1861,12 +1865,12 @@ uint64_t helper_le_ldq_cmmu(CPUArchState *env, target_ulong addr,
>                              TCGMemOpIdx oi, uintptr_t retaddr)
>  {
>      return load_helper(env, addr, oi, retaddr, MO_LEQ, true,
> -                       helper_le_ldq_cmmu, ldq_le_p);
> +                       helper_le_ldq_cmmu, ldq_le_p, ldq_be_p);
>  }
>  
>  uint64_t helper_be_ldq_cmmu(CPUArchState *env, target_ulong addr,
>                              TCGMemOpIdx oi, uintptr_t retaddr)
>  {
>      return load_helper(env, addr, oi, retaddr, MO_BEQ, true,
> -                       helper_be_ldq_cmmu, ldq_be_p);
> +                       helper_be_ldq_cmmu, ldq_be_p, ldq_le_p);
>  }
> 

Reviewed-by: David Hildenbrand <david@redhat.com>

-- 

Thanks,

David / dhildenb


  reply	other threads:[~2019-09-23  8:56 UTC|newest]

Thread overview: 53+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-09-22  3:54 [PATCH v3 00/20] Move rom and notdirty handling to cputlb Richard Henderson
2019-09-22  3:54 ` [PATCH v3 01/20] exec: Use TARGET_PAGE_BITS_MIN for TLB flags Richard Henderson
2019-09-23  8:24   ` David Hildenbrand
2019-09-22  3:54 ` [PATCH v3 02/20] exec: Split out variable page size support to exec-vary.c Richard Henderson
2019-09-23  8:26   ` David Hildenbrand
2019-09-23 16:27     ` Richard Henderson
2019-09-22  3:54 ` [PATCH v3 03/20] exec: Use const alias for TARGET_PAGE_BITS_VARY Richard Henderson
2019-09-22  3:54 ` [PATCH v3 04/20] exec: Restrict TARGET_PAGE_BITS_VARY assert to CONFIG_DEBUG_TCG Richard Henderson
2019-09-22  3:54 ` [PATCH v3 05/20] exec: Promote TARGET_PAGE_MASK to target_long Richard Henderson
2019-09-23  8:30   ` David Hildenbrand
2019-09-22  3:54 ` [PATCH v3 06/20] exec: Tidy TARGET_PAGE_ALIGN Richard Henderson
2019-09-23  8:30   ` David Hildenbrand
2019-09-22  3:54 ` [PATCH v3 07/20] exec: Cache TARGET_PAGE_MASK for TARGET_PAGE_BITS_VARY Richard Henderson
2019-09-23  8:31   ` David Hildenbrand
2019-09-22  3:54 ` [PATCH v3 08/20] cputlb: Disable __always_inline__ without optimization Richard Henderson
2019-09-23  9:18   ` Philippe Mathieu-Daudé
2019-09-23  9:45   ` Paolo Bonzini
2019-09-23 16:00     ` Richard Henderson
2019-09-23 16:49       ` Paolo Bonzini
2019-09-23 18:09         ` Richard Henderson
2019-09-22  3:54 ` [PATCH v3 09/20] cputlb: Replace switches in load/store_helper with callback Richard Henderson
2019-09-23  8:32   ` David Hildenbrand
2019-09-23  9:27   ` Philippe Mathieu-Daudé
2019-09-23  9:51   ` Paolo Bonzini
2019-09-23  9:54     ` David Hildenbrand
2019-09-23 10:02       ` Paolo Bonzini
2019-09-23 15:52         ` Richard Henderson
2019-09-23 18:18           ` Richard Henderson
2019-09-22  3:54 ` [PATCH v3 10/20] cputlb: Introduce TLB_BSWAP Richard Henderson
2019-09-23  8:33   ` David Hildenbrand [this message]
2019-09-22  3:54 ` [PATCH v3 11/20] exec: Adjust notdirty tracing Richard Henderson
2019-09-23  9:17   ` Philippe Mathieu-Daudé
2019-09-22  3:54 ` [PATCH v3 12/20] cputlb: Move ROM handling from I/O path to TLB path Richard Henderson
2019-09-23  8:39   ` David Hildenbrand
2019-09-22  3:54 ` [PATCH v3 13/20] cputlb: Move NOTDIRTY " Richard Henderson
2019-09-23  8:41   ` David Hildenbrand
2019-09-23  9:30   ` Philippe Mathieu-Daudé
2019-09-22  3:54 ` [PATCH v3 14/20] cputlb: Partially inline memory_region_section_get_iotlb Richard Henderson
2019-09-22  3:54 ` [PATCH v3 15/20] cputlb: Merge and move memory_notdirty_write_{prepare, complete} Richard Henderson
2019-09-22  3:54 ` [PATCH v3 16/20] cputlb: Handle TLB_NOTDIRTY in probe_access Richard Henderson
2019-09-22  3:54 ` [PATCH v3 17/20] cputlb: Remove cpu->mem_io_vaddr Richard Henderson
2019-09-23  8:50   ` David Hildenbrand
2019-09-22  3:54 ` [PATCH v3 18/20] cputlb: Remove tb_invalidate_phys_page_range is_cpu_write_access Richard Henderson
2019-09-23  8:52   ` David Hildenbrand
2019-09-23 16:05     ` Richard Henderson
2019-09-23 16:50       ` Paolo Bonzini
2019-09-22  3:54 ` [PATCH v3 19/20] cputlb: Pass retaddr to tb_invalidate_phys_page_fast Richard Henderson
2019-09-23  8:53   ` David Hildenbrand
2019-09-22  3:54 ` [PATCH v3 20/20] cputlb: Pass retaddr to tb_check_watchpoint Richard Henderson
2019-09-23  8:54   ` David Hildenbrand
2019-09-22  4:02 ` [PATCH v3 00/20] Move rom and notdirty handling to cputlb Richard Henderson
2019-09-22  6:46 ` no-reply
2019-09-23  8:23 ` David Hildenbrand

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