[PATCH 5.10 133/518] xen: use correct end address of kernel for conflict checking

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



5.10-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Juergen Gross <jgross@xxxxxxxx>

[ Upstream commit fac1bceeeb04886fc2ee952672e6e6c85ce41dca ]

When running as a Xen PV dom0 the kernel is loaded by the hypervisor
using a different memory map than that of the host. In order to
minimize the required changes in the kernel, the kernel adapts its
memory map to that of the host. In order to do that it is checking
for conflicts of its load address with the host memory map.

Unfortunately the tested memory range does not include the .brk
area, which might result in crashes or memory corruption when this
area does conflict with the memory map of the host.

Fix the test by using the _end label instead of __bss_stop.

Fixes: 808fdb71936c ("xen: check for kernel memory conflicting with memory layout")

Signed-off-by: Juergen Gross <jgross@xxxxxxxx>
Tested-by: Marek Marczykowski-Górecki <marmarek@xxxxxxxxxxxxxxxxxxxxxx>
Reviewed-by: Jan Beulich <jbeulich@xxxxxxxx>
Signed-off-by: Juergen Gross <jgross@xxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 arch/x86/xen/setup.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/xen/setup.c b/arch/x86/xen/setup.c
index 1f80dd3a2dd4a..629c94d1ab24c 100644
--- a/arch/x86/xen/setup.c
+++ b/arch/x86/xen/setup.c
@@ -856,7 +856,7 @@ char * __init xen_memory_setup(void)
 	 * to relocating (and even reusing) pages with kernel text or data.
 	 */
 	if (xen_is_e820_reserved(__pa_symbol(_text),
-			__pa_symbol(__bss_stop) - __pa_symbol(_text))) {
+				 __pa_symbol(_end) - __pa_symbol(_text))) {
 		xen_raw_console_write("Xen hypervisor allocated kernel memory conflicts with E820 map\n");
 		BUG();
 	}
-- 
2.43.0







[Index of Archives]     [Linux Kernel]     [Kernel Development Newbies]     [Linux USB Devel]     [Video for Linux]     [Linux Audio Users]     [Yosemite Hiking]     [Linux Kernel]     [Linux SCSI]

  Powered by Linux