Patch "um: Cleanup compiler warning in arch/x86/um/tls_32.c" has been added to the 5.19-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

This is a note to let you know that I've just added the patch titled

    um: Cleanup compiler warning in arch/x86/um/tls_32.c

to the 5.19-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     um-cleanup-compiler-warning-in-arch-x86-um-tls_32.c.patch
and it can be found in the queue-5.19 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.



commit b3aa287a9b066a474f56d45ab0dfe3e3643b8210
Author: Lukas Straub <lukasstraub2@xxxxxx>
Date:   Fri Aug 26 15:29:31 2022 +0000

    um: Cleanup compiler warning in arch/x86/um/tls_32.c
    
    [ Upstream commit d27fff3499671dc23a08efd01cdb8b3764a391c4 ]
    
    arch.tls_array is statically allocated so checking for NULL doesn't
    make sense. This causes the compiler warning below.
    
    Remove the checks to silence these warnings.
    
    ../arch/x86/um/tls_32.c: In function 'get_free_idx':
    ../arch/x86/um/tls_32.c:68:13: warning: the comparison will always evaluate as 'true' for the address of 'tls_array' will never be NULL [-Waddress]
       68 |         if (!t->arch.tls_array)
          |             ^
    In file included from ../arch/x86/um/asm/processor.h:10,
                     from ../include/linux/rcupdate.h:30,
                     from ../include/linux/rculist.h:11,
                     from ../include/linux/pid.h:5,
                     from ../include/linux/sched.h:14,
                     from ../arch/x86/um/tls_32.c:7:
    ../arch/x86/um/asm/processor_32.h:22:31: note: 'tls_array' declared here
       22 |         struct uml_tls_struct tls_array[GDT_ENTRY_TLS_ENTRIES];
          |                               ^~~~~~~~~
    ../arch/x86/um/tls_32.c: In function 'get_tls_entry':
    ../arch/x86/um/tls_32.c:243:13: warning: the comparison will always evaluate as 'true' for the address of 'tls_array' will never be NULL [-Waddress]
      243 |         if (!t->arch.tls_array)
          |             ^
    ../arch/x86/um/asm/processor_32.h:22:31: note: 'tls_array' declared here
       22 |         struct uml_tls_struct tls_array[GDT_ENTRY_TLS_ENTRIES];
          |                               ^~~~~~~~~
    
    Signed-off-by: Lukas Straub <lukasstraub2@xxxxxx>
    Acked-by: Randy Dunlap <rdunlap@xxxxxxxxxxxxx> # build-tested
    Signed-off-by: Richard Weinberger <richard@xxxxxx>
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

diff --git a/arch/x86/um/tls_32.c b/arch/x86/um/tls_32.c
index ac8eee093f9c..66162eafd8e8 100644
--- a/arch/x86/um/tls_32.c
+++ b/arch/x86/um/tls_32.c
@@ -65,9 +65,6 @@ static int get_free_idx(struct task_struct* task)
 	struct thread_struct *t = &task->thread;
 	int idx;
 
-	if (!t->arch.tls_array)
-		return GDT_ENTRY_TLS_MIN;
-
 	for (idx = 0; idx < GDT_ENTRY_TLS_ENTRIES; idx++)
 		if (!t->arch.tls_array[idx].present)
 			return idx + GDT_ENTRY_TLS_MIN;
@@ -240,9 +237,6 @@ static int get_tls_entry(struct task_struct *task, struct user_desc *info,
 {
 	struct thread_struct *t = &task->thread;
 
-	if (!t->arch.tls_array)
-		goto clear;
-
 	if (idx < GDT_ENTRY_TLS_MIN || idx > GDT_ENTRY_TLS_MAX)
 		return -EINVAL;