[Bug 2011421] [NEW] TDX azure instances crash during boot because of glibc bug

[Ioanna Alifieraki]

Public bug reported:

[IMPACT]

Glibc in jammy and kinetic is affected by the following bug :
https://sourceware.org/bugzilla/show_bug.cgi?id=29953

When cpuid reports no information on a shared cache, the
x86_non_temporal_threshold will be set to zero, causing memcpy/memset to
behave wrong for mid-sized operations. sysdeps/x86/dl-cacheinfo.h indicates
that the minimum value must be 0x4040, but this is not enforced for the
default value.

The issue was reported because jammy tdx instances are failing to boot
(crashing) on azure. The bug has been resolved upstream in
https://sourceware.org/git/gitweb.cgi?p=glibc.git;h=48b74865c63840b288bd85b4d8743533b73b339b

[TEST CASE]

Test case requires an azure tdx instance.
Microsoft has tested a test package with the above commit and
confirmed that instances boot successfully.

[REGRESSION POTENTIAL]

The patches have been accepted upstream. They modify code for x86 architecture, so any
potential regression would affect x86.

[OTHER]

Bug upstream: https://sourceware.org/bugzilla/show_bug.cgi?id=29953
Duplicate bug: https://sourceware.org/bugzilla/show_bug.cgi?id=30037

In jammy we need 2 commits :
https://sourceware.org/git/gitweb.cgi?p=glibc.git;h=b446822b6ae4e8149902a78cdd4a886634ad6321
https://sourceware.org/git/gitweb.cgi?p=glibc.git;h=48b74865c63840b288bd85b4d8743533b73b339b

In kinetic we just need :
https://sourceware.org/git/gitweb.cgi?p=glibc.git;h=48b74865c63840b288bd85b4d8743533b73b339b

** Affects: glibc (Ubuntu)
     Importance: Undecided
         Status: New

** Affects: glibc (Ubuntu Jammy)
     Importance: Undecided
         Status: Confirmed

** Affects: glibc (Ubuntu Kinetic)
     Importance: Undecided
         Status: Confirmed

** Also affects: glibc (Ubuntu Jammy)
   Importance: Undecided
       Status: New

** Also affects: glibc (Ubuntu Kinetic)
   Importance: Undecided
       Status: New

** Changed in: glibc (Ubuntu Jammy)
       Status: New => Confirmed

** Changed in: glibc (Ubuntu Kinetic)
       Status: New => Confirmed

** Description changed:

  [IMPACT]
  
  Glibc in jammy and kinetic is affected by the following bug :
  https://sourceware.org/bugzilla/show_bug.cgi?id=29953
  
- When cpuid reports no information on a shared cache, the 
- x86_non_temporal_threshold will be set to zero, causing memcpy/memset to 
- behave wrong for mid-sized operations. sysdeps/x86/dl-cacheinfo.h indicates 
- that the minimum value must be 0x4040, but this is not enforced for the 
+ When cpuid reports no information on a shared cache, the
+ x86_non_temporal_threshold will be set to zero, causing memcpy/memset to
+ behave wrong for mid-sized operations. sysdeps/x86/dl-cacheinfo.h indicates
+ that the minimum value must be 0x4040, but this is not enforced for the
  default value.
  
- 
- The issue was reported because jammy tdx instances are failing to boot 
- (crashing) on azure. The bug has been resolved upstream in 
+ The issue was reported because jammy tdx instances are failing to boot
+ (crashing) on azure. The bug has been resolved upstream in
  https://sourceware.org/git/gitweb.cgi?p=glibc.git;h=48b74865c63840b288bd85b4d8743533b73b339b
- 
  
  [TEST CASE]
  
  Test case requires an azure tdx instance.
  Microsoft has tested a test package with the above commit and
  confirmed that instances boot successfully.
  
  [REGRESSION POTENTIAL]
  
  The patches have been accepted upstream. They modify code for x86 architecture, so any
  potential regression would affect x86.
  
  [OTHER]
  
+ Bug upstream: https://sourceware.org/bugzilla/show_bug.cgi?id=29953
+ Duplicate bug: https://sourceware.org/bugzilla/show_bug.cgi?id=30037
+ 
  In jammy we need 2 commits :
  https://sourceware.org/git/gitweb.cgi?p=glibc.git;h=b446822b6ae4e8149902a78cdd4a886634ad6321
  https://sourceware.org/git/gitweb.cgi?p=glibc.git;h=48b74865c63840b288bd85b4d8743533b73b339b
  
  In kinetic we just need :
  https://sourceware.org/git/gitweb.cgi?p=glibc.git;h=48b74865c63840b288bd85b4d8743533b73b339b

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https://bugs.launchpad.net/bugs/2011421

Title:
  TDX azure instances crash during boot because of glibc bug

Status in glibc package in Ubuntu:
  New
Status in glibc source package in Jammy:
  Confirmed
Status in glibc source package in Kinetic:
  Confirmed

Bug description:
  [IMPACT]

  Glibc in jammy and kinetic is affected by the following bug :
  https://sourceware.org/bugzilla/show_bug.cgi?id=29953

  When cpuid reports no information on a shared cache, the
  x86_non_temporal_threshold will be set to zero, causing memcpy/memset to
  behave wrong for mid-sized operations. sysdeps/x86/dl-cacheinfo.h indicates
  that the minimum value must be 0x4040, but this is not enforced for the
  default value.

  The issue was reported because jammy tdx instances are failing to boot
  (crashing) on azure. The bug has been resolved upstream in
  https://sourceware.org/git/gitweb.cgi?p=glibc.git;h=48b74865c63840b288bd85b4d8743533b73b339b

  [TEST CASE]

  Test case requires an azure tdx instance.
  Microsoft has tested a test package with the above commit and
  confirmed that instances boot successfully.

  [REGRESSION POTENTIAL]

  The patches have been accepted upstream. They modify code for x86 architecture, so any
  potential regression would affect x86.

  [OTHER]

  Bug upstream: https://sourceware.org/bugzilla/show_bug.cgi?id=29953
  Duplicate bug: https://sourceware.org/bugzilla/show_bug.cgi?id=30037

  In jammy we need 2 commits :
  https://sourceware.org/git/gitweb.cgi?p=glibc.git;h=b446822b6ae4e8149902a78cdd4a886634ad6321
  https://sourceware.org/git/gitweb.cgi?p=glibc.git;h=48b74865c63840b288bd85b4d8743533b73b339b

  In kinetic we just need :
  https://sourceware.org/git/gitweb.cgi?p=glibc.git;h=48b74865c63840b288bd85b4d8743533b73b339b

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