[Mesa-dev] [PATCH 01/75] llvmpipe: Fix overflow for 32 bits available memory computation

[Axel Davy]

And cap to 2 GB on 32 bits.

Fixes https://bugs.freedesktop.org/show_bug.cgi?id=94561

Signed-off-by: Axel Davy <axel.davy at ens.fr>
Signed-off-by: Patrick Rudolph <siro at das-labor.org>
---
 src/gallium/auxiliary/os/os_misc.c       | 2 +-
 src/gallium/drivers/llvmpipe/lp_screen.c | 5 +++++
 2 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/src/gallium/auxiliary/os/os_misc.c b/src/gallium/auxiliary/os/os_misc.c
index 82e4957..4880392 100644
--- a/src/gallium/auxiliary/os/os_misc.c
+++ b/src/gallium/auxiliary/os/os_misc.c
@@ -128,7 +128,7 @@ os_get_total_physical_memory(uint64_t *size)
    const long phys_pages = sysconf(_SC_PHYS_PAGES);
    const long page_size = sysconf(_SC_PAGE_SIZE);
 
-   *size = phys_pages * page_size;
+   *size = (int64_t)phys_pages * (int64_t)page_size;
    return (phys_pages > 0 && page_size > 0);
 #elif defined(PIPE_OS_APPLE) || defined(PIPE_OS_BSD)
    size_t len = sizeof(*size);
diff --git a/src/gallium/drivers/llvmpipe/lp_screen.c b/src/gallium/drivers/llvmpipe/lp_screen.c
index 18837a2..fa5b5cf 100644
--- a/src/gallium/drivers/llvmpipe/lp_screen.c
+++ b/src/gallium/drivers/llvmpipe/lp_screen.c
@@ -280,6 +280,11 @@ llvmpipe_get_param(struct pipe_screen *screen, enum pipe_cap param)
       if (!os_get_total_physical_memory(&system_memory))
          return 0;
 
+#ifdef PIPE_ARCH_X86
+      /* cap to 2 GB on 32 bits system */
+      system_memory = MIN2(system_memory, 2048 << 20);
+#endif
+
       return (int)(system_memory >> 20);
    }
    case PIPE_CAP_UMA:
-- 
2.10.0