1 files changed, 21 insertions, 9 deletions

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 26237934ac87..ac04d9804391 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -107,9 +107,9 @@ config X86
         select HAVE_ARCH_SOFT_DIRTY
         select CLOCKSOURCE_WATCHDOG
         select GENERIC_CLOCKEVENTS
-        select ARCH_CLOCKSOURCE_DATA if X86_64
+        select ARCH_CLOCKSOURCE_DATA
         select GENERIC_CLOCKEVENTS_BROADCAST if X86_64 || (X86_32 && X86_LOCAL_APIC)
-        select GENERIC_TIME_VSYSCALL if X86_64
+        select GENERIC_TIME_VSYSCALL
         select KTIME_SCALAR if X86_32
         select GENERIC_STRNCPY_FROM_USER
         select GENERIC_STRNLEN_USER
@@ -1848,17 +1848,29 @@ config DEBUG_HOTPLUG_CPU0
           If unsure, say N.
 
 config COMPAT_VDSO
-        def_bool y
-        prompt "Compat VDSO support"
+        def_bool n
+        prompt "Disable the 32-bit vDSO (needed for glibc 2.3.3)"
         depends on X86_32 || IA32_EMULATION
         ---help---
-          Map the 32-bit VDSO to the predictable old-style address too.
+          Certain buggy versions of glibc will crash if they are
+          presented with a 32-bit vDSO that is not mapped at the address
+          indicated in its segment table.
 
-          Say N here if you are running a sufficiently recent glibc
-          version (2.3.3 or later), to remove the high-mapped
-          VDSO mapping and to exclusively use the randomized VDSO.
+          The bug was introduced by f866314b89d56845f55e6f365e18b31ec978ec3a
+          and fixed by 3b3ddb4f7db98ec9e912ccdf54d35df4aa30e04a and
+          49ad572a70b8aeb91e57483a11dd1b77e31c4468.  Glibc 2.3.3 is
+          the only released version with the bug, but OpenSUSE 9
+          contains a buggy "glibc 2.3.2".
 
-          If unsure, say Y.
+          The symptom of the bug is that everything crashes on startup, saying:
+          dl_main: Assertion `(void *) ph->p_vaddr == _rtld_local._dl_sysinfo_dso' failed!
+
+          Saying Y here changes the default value of the vdso32 boot
+          option from 1 to 0, which turns off the 32-bit vDSO entirely.
+          This works around the glibc bug but hurts performance.
+
+          If unsure, say N: if you are compiling your own kernel, you
+          are unlikely to be using a buggy version of glibc.
 
 config CMDLINE_BOOL
         bool "Built-in kernel command line"