diff --git a/gdb/testsuite/ChangeLog b/gdb/testsuite/ChangeLog
index ac4b6e1e55c..44afe3629b5 100644
--- a/gdb/testsuite/ChangeLog
+++ b/gdb/testsuite/ChangeLog
@@ -1,3 +1,24 @@
+2021-01-04  Simon Marchi  <simon.marchi@efficios.com>
+
+	* gdb.server/abspath.exp: Append "set sysroot" to GDBFLAGS.
+	* gdb.server/connect-without-multi-process.exp: Likewise.
+	* gdb.server/exit-multiple-threads.exp: Likewise.
+	* gdb.server/ext-attach.exp: Likewise.
+	* gdb.server/ext-restart.exp: Likewise.
+	* gdb.server/ext-run.exp: Likewise.
+	* gdb.server/ext-wrapper.exp: Likewise.
+	* gdb.server/multi-ui-errors.exp: Likewise.
+	* gdb.server/no-thread-db.exp: Likewise.
+	* gdb.server/reconnect-ctrl-c.exp: Likewise.
+	* gdb.server/run-without-local-binary.exp: Likewise.
+	* gdb.server/server-kill.exp: Likewise.
+	* gdb.server/server-run.exp: Likewise.
+	* gdb.server/solib-list.exp: Likewise.
+	* gdb.server/stop-reply-no-thread.exp: Likewise.
+	* gdb.server/wrapper.exp: Likewise.
+	* gdb.server/sysroot.exp: Increase timeout when testing the
+	target: sysroot.
+
 2021-01-04  Simon Marchi  <simon.marchi@efficios.com>
 
 	* gdb.server/server-run.exp: Use clean_restart.
diff --git a/gdb/testsuite/gdb.server/abspath.exp b/gdb/testsuite/gdb.server/abspath.exp
index f14bd90b8b8..1ccdbe7ac1c 100644
--- a/gdb/testsuite/gdb.server/abspath.exp
+++ b/gdb/testsuite/gdb.server/abspath.exp
@@ -33,8 +33,17 @@ if { [is_remote target] } {
     return 0
 }
 
-if { [prepare_for_testing "failed to prepare" $testfile $srcfile debug] } {
-    return -1
+save_vars { GDBFLAGS } {
+    # If GDB and GDBserver are both running locally, set the sysroot to avoid
+    # reading files via the remote protocol (the `is_remote target` check is
+    # already done above).
+    if { ![is_remote host] } {
+	set GDBFLAGS "$GDBFLAGS -ex \"set sysroot\""
+    }
+
+    if { [prepare_for_testing "failed to prepare" $testfile $srcfile debug] } {
+	return -1
+    }
 }
 
 # Make sure we're disconnected, in case we're testing with an
diff --git a/gdb/testsuite/gdb.server/connect-without-multi-process.exp b/gdb/testsuite/gdb.server/connect-without-multi-process.exp
index c36bd9b82d9..9c03d1280e1 100644
--- a/gdb/testsuite/gdb.server/connect-without-multi-process.exp
+++ b/gdb/testsuite/gdb.server/connect-without-multi-process.exp
@@ -31,9 +31,17 @@ if {[build_executable "failed to prepare" $testfile $srcfile debug]} {
 # Test spawning gdbserver with a program, connect to it and run to
 # main, with both multiprocess extensions on and off.
 proc do_test {multiprocess} {
-    global binfile
+    global binfile GDBFLAGS
 
-    clean_restart $binfile
+    save_vars { GDBFLAGS } {
+	# If GDB and GDBserver are both running locally, set the sysroot to avoid
+	# reading files via the remote protocol.
+	if { ![is_remote host] && ![is_remote target] } {
+	    set GDBFLAGS "$GDBFLAGS -ex \"set sysroot\""
+	}
+
+	clean_restart $binfile
+    }
 
     # Make sure we're disconnected, in case we're testing with an
     # extended-remote board, therefore already connected.
diff --git a/gdb/testsuite/gdb.server/exit-multiple-threads.exp b/gdb/testsuite/gdb.server/exit-multiple-threads.exp
index c0db6e9cd67..a74f7d12449 100644
--- a/gdb/testsuite/gdb.server/exit-multiple-threads.exp
+++ b/gdb/testsuite/gdb.server/exit-multiple-threads.exp
@@ -39,7 +39,17 @@ standard_testfile
 # Places a breakpoint in function 'breakpt' and then continues to the
 # breakpoint, at which point it runs 'info threads'.
 proc prepare_for_test { executable disable_multi_process } {
-    clean_restart ${executable}
+    global GDBFLAGS
+
+    save_vars { GDBFLAGS } {
+	# If GDB and GDBserver are both running locally, set the sysroot to avoid
+	# reading files via the remote protocol.
+	if { ![is_remote host] && ![is_remote target] } {
+	    set GDBFLAGS "$GDBFLAGS -ex \"set sysroot\""
+	}
+
+	clean_restart ${executable}
+    }
 
     # Make sure we're disconnected, in case we're testing with an
     # extended-remote board, therefore already connected.
diff --git a/gdb/testsuite/gdb.server/ext-attach.exp b/gdb/testsuite/gdb.server/ext-attach.exp
index 94695179dda..c9766e35317 100644
--- a/gdb/testsuite/gdb.server/ext-attach.exp
+++ b/gdb/testsuite/gdb.server/ext-attach.exp
@@ -30,8 +30,16 @@ if {![can_spawn_for_attach]} {
     return 0
 }
 
-if {[prepare_for_testing "failed to prepare" $testfile $srcfile debug]} {
-    return -1
+save_vars { GDBFLAGS } {
+    # If GDB and GDBserver are both running locally, set the sysroot to avoid
+    # reading files via the remote protocol.
+    if { ![is_remote host] && ![is_remote target] } {
+	set GDBFLAGS "$GDBFLAGS -ex \"set sysroot\""
+    }
+
+    if {[prepare_for_testing "failed to prepare" $testfile $srcfile debug]} {
+	return -1
+    }
 }
 
 # Make sure we're disconnected, in case we're testing with an
diff --git a/gdb/testsuite/gdb.server/ext-restart.exp b/gdb/testsuite/gdb.server/ext-restart.exp
index 33b13405391..8b175e75a77 100644
--- a/gdb/testsuite/gdb.server/ext-restart.exp
+++ b/gdb/testsuite/gdb.server/ext-restart.exp
@@ -25,8 +25,16 @@ if { [skip_gdbserver_tests] } {
     return 0
 }
 
-if { [prepare_for_testing "failed to prepare" $testfile $srcfile debug] } {
-    return -1
+save_vars { GDBFLAGS } {
+    # If GDB and GDBserver are both running locally, set the sysroot to avoid
+    # reading files via the remote protocol.
+    if { ![is_remote host] && ![is_remote target] } {
+	set GDBFLAGS "$GDBFLAGS -ex \"set sysroot\""
+    }
+
+    if { [prepare_for_testing "failed to prepare" $testfile $srcfile debug] } {
+	return -1
+    }
 }
 
 # Make sure we're disconnected, in case we're testing with an
diff --git a/gdb/testsuite/gdb.server/ext-run.exp b/gdb/testsuite/gdb.server/ext-run.exp
index 92aef141784..268f690949a 100644
--- a/gdb/testsuite/gdb.server/ext-run.exp
+++ b/gdb/testsuite/gdb.server/ext-run.exp
@@ -32,7 +32,15 @@ if {[build_executable $testfile.exp $testfile $srcfile debug] == -1} {
 # gdb_skip_xml_test must be called while gdb is not running.
 set do_xml_test [expr ![gdb_skip_xml_test]]
 
-clean_restart $binfile
+save_vars { GDBFLAGS } {
+    # If GDB and GDBserver are both running locally, set the sysroot to avoid
+    # reading files via the remote protocol.
+    if { ![is_remote host] && ![is_remote target] } {
+	set GDBFLAGS "$GDBFLAGS -ex \"set sysroot\""
+    }
+
+    clean_restart $binfile
+}
 
 # Make sure we're disconnected, in case we're testing with an
 # extended-remote board, therefore already connected.
diff --git a/gdb/testsuite/gdb.server/ext-wrapper.exp b/gdb/testsuite/gdb.server/ext-wrapper.exp
index c6e7786af42..fc9a77f137c 100644
--- a/gdb/testsuite/gdb.server/ext-wrapper.exp
+++ b/gdb/testsuite/gdb.server/ext-wrapper.exp
@@ -27,8 +27,16 @@ if {[build_executable $testfile.exp $testfile $srcfile debug] == -1} {
     return -1
 }
 
-if {[prepare_for_testing "failed to prepare" $testfile $srcfile debug]} {
-    return -1
+save_vars { GDBFLAGS } {
+    # If GDB and GDBserver are both running locally, set the sysroot to avoid
+    # reading files via the remote protocol.
+    if { ![is_remote host] && ![is_remote target] } {
+	set GDBFLAGS "$GDBFLAGS -ex \"set sysroot\""
+    }
+
+    if {[prepare_for_testing "failed to prepare" $testfile $srcfile debug]} {
+	return -1
+    }
 }
 
 # Make sure we're disconnected, in case we're testing with an
diff --git a/gdb/testsuite/gdb.server/multi-ui-errors.exp b/gdb/testsuite/gdb.server/multi-ui-errors.exp
index b89defc1ff4..073192f1971 100644
--- a/gdb/testsuite/gdb.server/multi-ui-errors.exp
+++ b/gdb/testsuite/gdb.server/multi-ui-errors.exp
@@ -28,8 +28,16 @@ if {[skip_gdbserver_tests]} {
     return 0
 }
 
-if {[prepare_for_testing "failed to prepare" ${testfile} ${srcfile}]} {
-    return -1
+save_vars { GDBFLAGS } {
+    # If GDB and GDBserver are both running locally, set the sysroot to avoid
+    # reading files via the remote protocol.
+    if { ![is_remote host] && ![is_remote target] } {
+	set GDBFLAGS "$GDBFLAGS -ex \"set sysroot\""
+    }
+
+    if {[prepare_for_testing "failed to prepare" ${testfile} ${srcfile}]} {
+	return -1
+    }
 }
 
 # Make sure we're disconnected, in case we're testing with an
diff --git a/gdb/testsuite/gdb.server/no-thread-db.exp b/gdb/testsuite/gdb.server/no-thread-db.exp
index 5dbb65469bb..19ec89a822f 100644
--- a/gdb/testsuite/gdb.server/no-thread-db.exp
+++ b/gdb/testsuite/gdb.server/no-thread-db.exp
@@ -33,7 +33,15 @@ if {[gdb_compile_pthreads "${srcdir}/${subdir}/${srcfile}" "${binfile}" executab
     return -1
 }
 
-clean_restart ${testfile}
+save_vars { GDBFLAGS } {
+    # If GDB and GDBserver are both running locally, set the sysroot to avoid
+    # reading files via the remote protocol.
+    if { ![is_remote host] && ![is_remote target] } {
+	set GDBFLAGS "$GDBFLAGS -ex \"set sysroot\""
+    }
+
+    clean_restart ${testfile}
+}
 
 # Make sure we're disconnected, in case we're testing with an
 # extended-remote board, therefore already connected.
diff --git a/gdb/testsuite/gdb.server/reconnect-ctrl-c.exp b/gdb/testsuite/gdb.server/reconnect-ctrl-c.exp
index 9b5b7a83328..11aa5147c78 100644
--- a/gdb/testsuite/gdb.server/reconnect-ctrl-c.exp
+++ b/gdb/testsuite/gdb.server/reconnect-ctrl-c.exp
@@ -30,8 +30,17 @@ if [target_info exists gdb,nointerrupts] {
 }
 
 standard_testfile
-if [prepare_for_testing "failed to prepare" $testfile $srcfile] {
-    return -1
+
+save_vars { GDBFLAGS } {
+    # If GDB and GDBserver are both running locally, set the sysroot to avoid
+    # reading files via the remote protocol.
+    if { ![is_remote host] && ![is_remote target] } {
+	set GDBFLAGS "$GDBFLAGS -ex \"set sysroot\""
+    }
+
+    if [prepare_for_testing "failed to prepare" $testfile $srcfile] {
+	return -1
+    }
 }
 
 # Make sure we're disconnected, in case we're testing with an
diff --git a/gdb/testsuite/gdb.server/run-without-local-binary.exp b/gdb/testsuite/gdb.server/run-without-local-binary.exp
index 6bbdca278c6..395eddc9106 100644
--- a/gdb/testsuite/gdb.server/run-without-local-binary.exp
+++ b/gdb/testsuite/gdb.server/run-without-local-binary.exp
@@ -31,6 +31,13 @@ if {[prepare_for_testing "failed to prepare" $testfile $srcfile debug]} {
 # remote/21852.
 save_vars { GDBFLAGS } {
     set GDBFLAGS ""
+
+    # If GDB and GDBserver are both running locally, set the sysroot to avoid
+    # reading files via the remote protocol.
+    if { ![is_remote host] && ![is_remote target] } {
+	set GDBFLAGS "-ex \"set sysroot\""
+    }
+
     gdb_exit
     gdb_start
 
diff --git a/gdb/testsuite/gdb.server/server-kill.exp b/gdb/testsuite/gdb.server/server-kill.exp
index ab82072138a..80d78f89738 100644
--- a/gdb/testsuite/gdb.server/server-kill.exp
+++ b/gdb/testsuite/gdb.server/server-kill.exp
@@ -36,8 +36,17 @@ if { [build_executable "failed to prepare" ${testfile}] } {
 proc prepare {} {
     global binfile gdb_prompt srcfile decimal
     global server_pid
+    global GDBFLAGS
 
-    clean_restart $binfile
+    save_vars { GDBFLAGS } {
+	# If GDB and GDBserver are both running locally, set the sysroot to avoid
+	# reading files via the remote protocol.
+	if { ![is_remote host] && ![is_remote target] } {
+	    set GDBFLAGS "$GDBFLAGS -ex \"set sysroot\""
+	}
+
+	clean_restart $binfile
+    }
 
     # Make sure we're disconnected, in case we're testing with an
     # extended-remote board, therefore already connected.
diff --git a/gdb/testsuite/gdb.server/server-run.exp b/gdb/testsuite/gdb.server/server-run.exp
index 72ba02c977c..e680ef50035 100644
--- a/gdb/testsuite/gdb.server/server-run.exp
+++ b/gdb/testsuite/gdb.server/server-run.exp
@@ -29,7 +29,15 @@ if {[build_executable $testfile.exp $testfile $srcfile debug] == -1} {
     return -1
 }
 
-clean_restart $binfile
+save_vars { GDBFLAGS } {
+    # If GDB and GDBserver are both running locally, set the sysroot to avoid
+    # reading files via the remote protocol.
+    if { ![is_remote host] && ![is_remote target] } {
+	set GDBFLAGS "$GDBFLAGS -ex \"set sysroot\""
+    }
+
+    clean_restart $binfile
+}
 
 # Make sure we're disconnected, in case we're testing with an
 # extended-remote board, therefore already connected.
diff --git a/gdb/testsuite/gdb.server/solib-list.exp b/gdb/testsuite/gdb.server/solib-list.exp
index c4934ed1416..3a8c739dd7b 100644
--- a/gdb/testsuite/gdb.server/solib-list.exp
+++ b/gdb/testsuite/gdb.server/solib-list.exp
@@ -42,7 +42,16 @@ set interp_system [section_get ${binfile} .interp]
 verbose -log "system interpreter is: $interp_system"
 
 foreach nonstop { 0 1 } { with_test_prefix "non-stop $nonstop" {
-    clean_restart
+    save_vars { GDBFLAGS } {
+	# If GDB and GDBserver are both running locally, set the sysroot to avoid
+	# reading files via the remote protocol.
+	if { ![is_remote host] && ![is_remote target] } {
+	    set GDBFLAGS "$GDBFLAGS -ex \"set sysroot\""
+	}
+
+	clean_restart
+    }
+
     gdb_load_shlib ${binlibfile}
 
     set remote_binfile [gdb_remote_download target $binfile]
diff --git a/gdb/testsuite/gdb.server/stop-reply-no-thread.exp b/gdb/testsuite/gdb.server/stop-reply-no-thread.exp
index 5e93b4770aa..68bf42ac1a0 100644
--- a/gdb/testsuite/gdb.server/stop-reply-no-thread.exp
+++ b/gdb/testsuite/gdb.server/stop-reply-no-thread.exp
@@ -34,9 +34,17 @@ if { [build_executable "failed to prepare" $testfile $srcfile] == -1 } {
 
 # Run the tests with different features of GDBserver disabled.
 proc run_test { disable_feature target_nonstop } {
-    global binfile gdb_prompt decimal
+    global binfile gdb_prompt decimal GDBFLAGS
 
-    clean_restart ${binfile}
+    save_vars { GDBFLAGS } {
+	# If GDB and GDBserver are both running locally, set the sysroot to avoid
+	# reading files via the remote protocol.
+	if { ![is_remote host] && ![is_remote target] } {
+	    set GDBFLAGS "$GDBFLAGS -ex \"set sysroot\""
+	}
+
+	clean_restart ${binfile}
+    }
 
     # Make sure we're disconnected, in case we're testing with an
     # extended-remote board, therefore already connected.
diff --git a/gdb/testsuite/gdb.server/sysroot.exp b/gdb/testsuite/gdb.server/sysroot.exp
index 158b7c5d0b8..5aea60a526b 100644
--- a/gdb/testsuite/gdb.server/sysroot.exp
+++ b/gdb/testsuite/gdb.server/sysroot.exp
@@ -40,39 +40,45 @@ foreach_with_prefix sysroot { "local" "remote" } {
     if { $sysroot == "local" } {
 	set sysroot_command "/"
 	set reading_symbols "Reading symbols from $binfile..."
+	set timeout_factor 1
     } else {
 	set sysroot_command "target:"
 	set reading_symbols "Reading $binfile from remote target..."
+	set timeout_factor 5
     }
 
-    # Restart GDB.
-    clean_restart
+    # Reading debug info from the remote target can take a bit of time, so
+    # increase the timeout in that case.
+    with_timeout_factor $timeout_factor {
+	# Restart GDB.
+	clean_restart
 
-    # Make sure we're disconnected, in case we're testing with an
-    # extended-remote board, therefore already connected.
-    gdb_test "disconnect" ".*"
+	# Make sure we're disconnected, in case we're testing with an
+	# extended-remote board, therefore already connected.
+	gdb_test "disconnect" ".*"
 
-    # Start GDBserver.
-    set res [gdbserver_start "" $binfile]
-    set gdbserver_protocol [lindex $res 0]
-    set gdbserver_gdbport [lindex $res 1]
+	# Start GDBserver.
+	set res [gdbserver_start "" $binfile]
+	set gdbserver_protocol [lindex $res 0]
+	set gdbserver_gdbport [lindex $res 1]
 
-    # Set the sysroot.
-    gdb_test_no_output "set sysroot $sysroot_command"
+	# Set the sysroot.
+	gdb_test_no_output "set sysroot $sysroot_command"
 
-    # Connect to gdbserver, making sure GDB reads in the binary correctly.
-    set test "connect to remote and read binary"
-    if {[gdb_target_cmd $gdbserver_protocol $gdbserver_gdbport $reading_symbols] == 0} {
-	pass $test
-    } else {
-	fail $test
+	# Connect to gdbserver, making sure GDB reads in the binary correctly.
+	set test "connect to remote and read binary"
+	if {[gdb_target_cmd $gdbserver_protocol $gdbserver_gdbport $reading_symbols] == 0} {
+	    pass $test
+	} else {
+	    fail $test
+	}
+
+	gdb_breakpoint main
+	gdb_test "continue" "Breakpoint $decimal.* main.*" "continue to main"
+
+	# Test that we can stop inside a library.
+	gdb_breakpoint printf
+	gdb_test "continue" "Breakpoint $decimal.* (__)?printf .*" \
+	    "continue to printf"
     }
-
-    gdb_breakpoint main
-    gdb_test "continue" "Breakpoint $decimal.* main.*" "continue to main"
-
-    # Test that we can stop inside a library.
-    gdb_breakpoint printf
-    gdb_test "continue" "Breakpoint $decimal.* (__)?printf .*" \
-	"continue to printf"
 }
diff --git a/gdb/testsuite/gdb.server/wrapper.exp b/gdb/testsuite/gdb.server/wrapper.exp
index 695deea174d..27d37bac02e 100644
--- a/gdb/testsuite/gdb.server/wrapper.exp
+++ b/gdb/testsuite/gdb.server/wrapper.exp
@@ -31,8 +31,16 @@ if { [istarget *-*-mingw*]
     return -1
 }
 
-if { [prepare_for_testing "failed to prepare" $testfile $srcfile debug] } {
-    return -1
+save_vars { GDBFLAGS } {
+    # If GDB and GDBserver are both running locally, set the sysroot to avoid
+    # reading files via the remote protocol.
+    if { ![is_remote host] && ![is_remote target] } {
+	set GDBFLAGS "$GDBFLAGS -ex \"set sysroot\""
+    }
+
+    if { [prepare_for_testing "failed to prepare" $testfile $srcfile debug] } {
+	return -1
+    }
 }
 
 # Make sure we're disconnected, in case we're testing with an