Migration pull for 9.0-rc0

- Nicholas/Phil's fix on migration corruption / inconsistent for tcg
 - Cedric's fix on block migration over n_sectors==0
 - Steve's CPR reboot documentation page
 - Fabiano's misc fixes on mapped-ram (IOC leak, dup() errors, fd checks, fd
   use race, etc.)
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Merge tag 'migration-20240317-pull-request' of https://gitlab.com/peterx/qemu into staging

Migration pull for 9.0-rc0

- Nicholas/Phil's fix on migration corruption / inconsistent for tcg
- Cedric's fix on block migration over n_sectors==0
- Steve's CPR reboot documentation page
- Fabiano's misc fixes on mapped-ram (IOC leak, dup() errors, fd checks, fd
  use race, etc.)

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# gpg: Signature made Sun 17 Mar 2024 20:56:50 GMT
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# gpg: Good signature from "Peter Xu <xzpeter@gmail.com>" [marginal]
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* tag 'migration-20240317-pull-request' of https://gitlab.com/peterx/qemu:
  migration/multifd: Duplicate the fd for the outgoing_args
  migration/multifd: Ensure we're not given a socket for file migration
  migration: Fix iocs leaks during file and fd migration
  migration: cpr-reboot documentation
  migration: Skip only empty block devices
  physmem: Fix migration dirty bitmap coherency with TCG memory access
  physmem: Factor cpu_physical_memory_dirty_bits_cleared() out
  physmem: Expose tlb_reset_dirty_range_all()
  migration: Fix error handling after dup in file migration
  io: Introduce qio_channel_file_new_dupfd

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

include/exec/exec-all.h

@@ -655,6 +655,7 @@ static inline void mmap_unlock(void) {}
 
 void tlb_reset_dirty(CPUState *cpu, ram_addr_t start1, ram_addr_t length);
 void tlb_set_dirty(CPUState *cpu, vaddr addr);
+void tlb_reset_dirty_range_all(ram_addr_t start, ram_addr_t length);
 
 MemoryRegionSection *
 address_space_translate_for_iotlb(CPUState *cpu, int asidx, hwaddr addr,

include/exec/ram_addr.h

@@ -25,6 +25,7 @@
 #include "sysemu/tcg.h"
 #include "exec/ramlist.h"
 #include "exec/ramblock.h"
+#include "exec/exec-all.h"
 
 extern uint64_t total_dirty_pages;
 
@@ -443,6 +444,14 @@ uint64_t cpu_physical_memory_set_dirty_lebitmap(unsigned long *bitmap,
 }
 #endif /* not _WIN32 */
 
+static inline void cpu_physical_memory_dirty_bits_cleared(ram_addr_t start,
+                                                          ram_addr_t length)
+{
+    if (tcg_enabled()) {
+        tlb_reset_dirty_range_all(start, length);
+    }
+
+}
 bool cpu_physical_memory_test_and_clear_dirty(ram_addr_t start,
                                               ram_addr_t length,
                                               unsigned client);
@@ -504,6 +513,9 @@ uint64_t cpu_physical_memory_sync_dirty_bitmap(RAMBlock *rb,
                 idx++;
             }
         }
+        if (num_dirty) {
+            cpu_physical_memory_dirty_bits_cleared(start, length);
+        }
 
         if (rb->clear_bmap) {
             /*

include/io/channel-file.h

@@ -68,6 +68,24 @@ struct QIOChannelFile {
 QIOChannelFile *
 qio_channel_file_new_fd(int fd);
 
+/**
+ * qio_channel_file_new_dupfd:
+ * @fd: the file descriptor
+ * @errp: pointer to initialized error object
+ *
+ * Create a new IO channel object for a file represented by the @fd
+ * parameter. Like qio_channel_file_new_fd(), but the @fd is first
+ * duplicated with dup().
+ *
+ * The channel will own the duplicated file descriptor and will take
+ * responsibility for closing it, the original FD is owned by the
+ * caller.
+ *
+ * Returns: the new channel object
+ */
+QIOChannelFile *
+qio_channel_file_new_dupfd(int fd, Error **errp);
+
 /**
  * qio_channel_file_new_path:
  * @path: the file path