linux-user/elfload: add extra logging for hole finding

The various approaches to finding memory holes are quite complicated
to follow especially at a distance. Improve the logging so we can see
exactly what method found the space for the guest memory.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Warner Losh <imp@bsdimp.com>
Message-Id: <20220105135009.1584676-26-alex.bennee@linaro.org>

1 files changed, 18 insertions, 0 deletions

diff --git a/linux-user/elfload.c b/linux-user/elfload.c
index fc23a6dcf6..30dbb005c2 100644
--- a/linux-user/elfload.c
+++ b/linux-user/elfload.c
@@ -2267,6 +2267,9 @@ static void pgb_have_guest_base(const char *image_name, abi_ulong guest_loaddr,
     if (test != addr) {
         pgb_fail_in_use(image_name);
     }
+    qemu_log_mask(CPU_LOG_PAGE,
+                  "%s: base @ %p for " TARGET_ABI_FMT_ld " bytes\n",
+                  __func__, addr, guest_hiaddr - guest_loaddr);
 }
 
 /**
@@ -2309,6 +2312,9 @@ static uintptr_t pgd_find_hole_fallback(uintptr_t guest_size, uintptr_t brk,
             if (mmap_start != MAP_FAILED) {
                 munmap(mmap_start, guest_size);
                 if (mmap_start == (void *) align_start) {
+                    qemu_log_mask(CPU_LOG_PAGE,
+                                  "%s: base @ %p for %" PRIdPTR" bytes\n",
+                                  __func__, mmap_start + offset, guest_size);
                     return (uintptr_t) mmap_start + offset;
                 }
             }
@@ -2388,6 +2394,12 @@ static uintptr_t pgb_find_hole(uintptr_t guest_loaddr, uintptr_t guest_size,
     }
     free_self_maps(maps);
 
+    if (ret != -1) {
+        qemu_log_mask(CPU_LOG_PAGE, "%s: base @ %" PRIxPTR
+                      " for %" PRIuPTR " bytes\n",
+                      __func__, ret, guest_size);
+    }
+
     return ret;
 }
 
@@ -2439,6 +2451,9 @@ static void pgb_static(const char *image_name, abi_ulong orig_loaddr,
     }
 
     guest_base = addr;
+
+    qemu_log_mask(CPU_LOG_PAGE, "%s: base @ %"PRIxPTR" for %" PRIuPTR" bytes\n",
+                  __func__, addr, hiaddr - loaddr);
 }
 
 static void pgb_dynamic(const char *image_name, long align)
@@ -2495,6 +2510,9 @@ static void pgb_reserved_va(const char *image_name, abi_ulong guest_loaddr,
                      "using -R option)", reserved_va, test, strerror(errno));
         exit(EXIT_FAILURE);
     }
+
+    qemu_log_mask(CPU_LOG_PAGE, "%s: base @ %p for %lu bytes\n",
+                  __func__, addr, reserved_va);
 }
 
 void probe_guest_base(const char *image_name, abi_ulong guest_loaddr,