** Description changed:

  The issue was detected when building openjdk-17[1].
  
- The bug occurs due to the introduction of a new guard mechanism[2] 
ALLOCATE_GUARD_MADV_GUARD. 
+ The bug occurs due to the introduction of a new guard mechanism[2] 
ALLOCATE_GUARD_MADV_GUARD.
  This is a default value for the stack protection guard  (0) and it is 
unchanged when the thread is created with 0 size guard area[3]. The stack block 
is added to the list of the stacks in use[4].
  The first thread runs its course and exits.
  
  When the subsequent thread is created with non-zero guard area, the existing 
stack can be reused[5].
- It has ALLOCATE_GUARD_MADV_GUARD stack protection flag set, but the kernel 
does not support it. adjust_stack_prot function will try to adjust the guard 
area[6], but the call will fail with EINVAL. 
+ It has ALLOCATE_GUARD_MADV_GUARD stack protection flag set, but the kernel 
does not support it. adjust_stack_prot function will try to adjust the guard 
area[6], but the call will fail with EINVAL.
+ 
+ The client application will fail to create the thread.
  
  This breaks OpenJDK and other multithreaded applications running glibc
  2.42-0ubuntu1 on kernels < 6.13.
- 
  
  [1] 
https://launchpad.net/ubuntu/+source/openjdk-17/17.0.17~5ea-1/+build/31115316
  [2] 
https://github.com/bminor/glibc/commit/a6fbe36b7f31292981422692236465ab56670ea9
  [3] 
https://github.com/bminor/glibc/blob/0c6cb5285bc90b35dfdb476f47fe9bad721abf8b/nptl/allocatestack.c#L191
  [4] 
https://github.com/bminor/glibc/blob/0c6cb5285bc90b35dfdb476f47fe9bad721abf8b/nptl/allocatestack.c#L558
  [5] 
https://github.com/bminor/glibc/blob/0c6cb5285bc90b35dfdb476f47fe9bad721abf8b/nptl/allocatestack.c#L483
  [6] 
https://github.com/bminor/glibc/blob/0c6cb5285bc90b35dfdb476f47fe9bad721abf8b/nptl/allocatestack.c#L256

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https://bugs.launchpad.net/bugs/2121834

Title:
  glibc 2.42-0ubuntu1 fails to start the thread on kernel < 6.13

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