Re: PR/54093 CVS commit: src

[Takeshi Nakayama <nakayama%NetBSD.org@localhost>]

>>> Takeshi Nakayama <nakayama%NetBSD.org@localhost> wrote

> >>> Joerg Sonnenberger <joerg%bec.de@localhost> wrote
> 
> > >  I think static TLS area should align with p_align in elf program
> > >  header, not with sizeof(max_align_t).
> > 
> > We don't support non-standard alignments of TLS. Fixing that is
> > intrusive in the dynamic linker and I have no plan to do that ATM.
> 
> Should we follow p_align for static linking?  Since it is now
> aligned with a value different from p_align, some atf tests fails
> on amd64 like sparc before the change.  Previously, p_align and
> sizeof(void *) had the same value on amd64 by chance.

I prepared a patch that simplified my previous patch to fix for
static linking.  Is it okay to commit?

The rounding logic should be correct because it does the same thing
as _rtld_tls_offset_allocate in libexec/ld.elf_so/tls.c.

  https://nxr.netbsd.org/xref/src/libexec/ld.elf_so/tls.c#234

-- Takeshi Nakayama


Index: lib/libc/tls/Makefile.inc
===================================================================
RCS file: /cvsroot/src/lib/libc/tls/Makefile.inc,v
retrieving revision 1.3
diff -u -d -r1.3 Makefile.inc
--- lib/libc/tls/Makefile.inc	4 Nov 2019 12:45:10 -0000	1.3
+++ lib/libc/tls/Makefile.inc	6 Nov 2019 06:29:53 -0000
@@ -6,4 +6,4 @@
 .PATH:	${.PARSEDIR} ${ARCHDIR}/tls
 
 SRCS+=			tls.c
-CPPFLAGS.tls.c+=	-D_LIBC_SOURCE -std=gnu11
+CPPFLAGS.tls.c+=	-D_LIBC_SOURCE
Index: lib/libc/tls/tls.c
===================================================================
RCS file: /cvsroot/src/lib/libc/tls/tls.c,v
retrieving revision 1.11
diff -u -d -r1.11 tls.c
--- lib/libc/tls/tls.c	5 Nov 2019 22:22:42 -0000	1.11
+++ lib/libc/tls/tls.c	6 Nov 2019 06:29:53 -0000
@@ -46,7 +46,6 @@
 #include <link_elf.h>
 #include <lwp.h>
 #include <stdbool.h>
-#include <stdalign.h>
 #include <stddef.h>
 #include <stdlib.h>
 #include <string.h>
@@ -85,9 +84,6 @@
 	uint8_t *p;
 
 	if (initial_thread_tcb == NULL) {
-#ifdef __HAVE_TLS_VARIANT_II
-		tls_size = roundup2(tls_size, alignof(max_align_t));
-#endif
 		tls_allocation = tls_size + sizeof(*tcb);
 
 		initial_thread_tcb = p = mmap(NULL, tls_allocation,
@@ -105,7 +101,7 @@
 	tcb = (struct tls_tcb *)p;
 	p += sizeof(struct tls_tcb);
 #else
-	/* LINTED tls_size is rounded above */
+	/* LINTED tls_size is rounded in __libc_static_tls_setup_cb */
 	tcb = (struct tls_tcb *)(p + tls_size);
 	tcb->tcb_self = tcb;
 #endif
@@ -149,7 +145,11 @@
 			continue;
 		tls_initaddr = (void *)(phdr->p_vaddr + data->dlpi_addr);
 		tls_initsize = phdr->p_filesz;
+#ifdef __HAVE_TLS_VARIANT_I
 		tls_size = phdr->p_memsz;
+#else
+		tls_size = roundup2(phdr->p_memsz, phdr->p_align);
+#endif
 	}
 	return 0;
 }