qemu-trivial
[Top][All Lists]
Advanced

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [RFC PATCH-for-7.0] hw/i386/amd_iommu: Fix maybe-uninitialized error


From: Philippe Mathieu-Daudé
Subject: Re: [RFC PATCH-for-7.0] hw/i386/amd_iommu: Fix maybe-uninitialized error with GCC 12
Date: Fri, 18 Mar 2022 15:03:41 +0100
User-agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:91.0) Gecko/20100101 Thunderbird/91.7.0

+qemu-trivial@

On 18/3/22 01:41, Philippe Mathieu-Daudé wrote:
From: Philippe Mathieu-Daudé <f4bug@amsat.org>

Initialize 'oldlevel' early to avoid on Debian/sid:

   FAILED: libqemu-x86_64-softmmu.fa.p/hw_i386_amd_iommu.c.o
   In function 'pte_get_page_mask',
       inlined from 'amdvi_page_walk' at hw/i386/amd_iommu.c:945:25,
       inlined from 'amdvi_do_translate' at hw/i386/amd_iommu.c:989:5,
       inlined from 'amdvi_translate' at hw/i386/amd_iommu.c:1038:5:
   hw/i386/amd_iommu.c:877:38: error: 'oldlevel' may be used uninitialized 
[-Werror=maybe-uninitialized]
     877 |     return ~((1UL << ((oldlevel * 9) + 3)) - 1);
         |                      ~~~~~~~~~~~~~~~~^~~~
   hw/i386/amd_iommu.c: In function 'amdvi_translate':
   hw/i386/amd_iommu.c:906:41: note: 'oldlevel' was declared here
     906 |     unsigned level, present, pte_perms, oldlevel;
         |                                         ^~~~~~~~
   cc1: all warnings being treated as errors

Having:

   $ gcc --version
   gcc (Debian 12-20220313-1) 12.0.1 20220314 (experimental)

Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
---
  hw/i386/amd_iommu.c | 1 +
  1 file changed, 1 insertion(+)

diff --git a/hw/i386/amd_iommu.c b/hw/i386/amd_iommu.c
index 4d13d8e697..b6d299f964 100644
--- a/hw/i386/amd_iommu.c
+++ b/hw/i386/amd_iommu.c
@@ -904,6 +904,7 @@ static void amdvi_page_walk(AMDVIAddressSpace *as, uint64_t 
*dte,
      /* make sure the DTE has TV = 1 */
      if (pte & AMDVI_DEV_TRANSLATION_VALID) {
          level = get_pte_translation_mode(pte);
+        oldlevel = level;
          if (level >= 7) {
              trace_amdvi_mode_invalid(level, addr);
              return;




reply via email to

[Prev in Thread] Current Thread [Next in Thread]