WSL2-Linux-Kernel/arch/arc
Pavel Kozlov 4fd9df10cb ARC: mm: fix leakage of memory allocated for PTE
Since commit d9820ff ("ARC: mm: switch pgtable_t back to struct page *")
a memory leakage problem occurs. Memory allocated for page table entries
not released during process termination. This issue can be reproduced by
a small program that allocates a large amount of memory. After several
runs, you'll see that the amount of free memory has reduced and will
continue to reduce after each run. All ARC CPUs are effected by this
issue. The issue was introduced since the kernel stable release v5.15-rc1.

As described in commit d9820ff after switch pgtable_t back to struct
page *, a pointer to "struct page" and appropriate functions are used to
allocate and free a memory page for PTEs, but the pmd_pgtable macro hasn't
changed and returns the direct virtual address from the PMD (PGD) entry.
Than this address used as a parameter in the __pte_free() and as a result
this function couldn't release memory page allocated for PTEs.

Fix this issue by changing the pmd_pgtable macro and returning pointer to
struct page.

Fixes: d9820ff76f ("ARC: mm: switch pgtable_t back to struct page *")
Cc: Mike Rapoport <rppt@kernel.org>
Cc: <stable@vger.kernel.org> # 5.15.x
Signed-off-by: Pavel Kozlov <pavel.kozlov@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@kernel.org>
2022-10-17 16:32:12 -07:00
..
boot arc: dts: Harmonize EHCI/OHCI DT nodes name 2022-10-17 16:32:12 -07:00
configs arc: update config files 2022-10-17 16:32:12 -07:00
include ARC: mm: fix leakage of memory allocated for PTE 2022-10-17 16:32:12 -07:00
kernel ARC: Fix comment typo 2022-10-17 16:32:11 -07:00
lib
mm arc: iounmap() arg is volatile 2022-10-17 16:32:12 -07:00
plat-axs10x
plat-hsdk
plat-sim
plat-tb10x
Kbuild
Kconfig
Kconfig.debug
Makefile