Helge Deller 70be49f2f6 parisc: Fix userspace graphics card breakage due to pgtable special bit ... Commit df24e1783e ("parisc: Add vDSO support") introduced the vDSO support, for which a _PAGE_SPECIAL page table flag was needed. Since we wanted to keep every page table entry in 32-bits, this patch re-used the existing - but yet unused - _PAGE_DMB flag (which triggers a hardware break if a page is accessed) to store the special bit. But when graphics card memory is mmapped into userspace, the kernel uses vm_iomap_memory() which sets the the special flag. So, with the DMB bit set, every access to the graphics memory now triggered a hardware exception and segfaulted the userspace program. Fix this breakage by dropping the DMB bit when writing the page protection bits to the CPU TLB. In addition this patch adds a small optimization: if huge pages aren't configured (which is at least the case for 32-bit kernels), then the special bit is stored in the hpage (HUGE PAGE) bit instead. That way we can skip to reset the DMB bit. Fixes: df24e1783e ("parisc: Add vDSO support") Cc: <stable@vger.kernel.org> # 5.18+ Signed-off-by: Helge Deller <deller@gmx.de>		2022-10-14 10:45:12 +02:00
..
boot	Kbuild updates for v5.17	2022-01-19 11:15:19 +02:00
configs	parisc: Update 32- and 64-bit defconfigs	2022-05-08 20:01:11 +02:00
include	parisc: Fix userspace graphics card breakage due to pgtable special bit	2022-10-14 10:45:12 +02:00
kernel	parisc: Fix userspace graphics card breakage due to pgtable special bit	2022-10-14 10:45:12 +02:00
lib	parisc: Use constants to encode the space registers like SR_KERNEL	2022-03-11 19:49:31 +01:00
math-emu	parisc: align '*' in comment in math-emu code	2022-06-26 00:19:27 +02:00
mm	- The usual batches of cleanups from Baoquan He, Muchun Song, Miaohe	2022-08-05 16:32:45 -07:00
defpalo.conf
install.sh	kbuild: factor out the common installation code into scripts/install.sh	2022-05-11 21:45:53 +09:00
Kbuild	kbuild: use more subdir- for visiting subdirectories while cleaning	2021-10-24 13:49:46 +09:00
Kconfig	parisc: Allow CONFIG_64BIT with ARCH=parisc	2022-09-15 07:59:37 +02:00
Kconfig.debug	tracing: Refactor TRACE_IRQFLAGS_SUPPORT in Kconfig	2021-08-16 11:37:21 -04:00
Makefile	parisc: remove arch/parisc/nm	2022-05-29 18:39:35 +09:00