kernel.git/arch/powerpc/kernel/vdso/cacheflush.S, branch linux-6.10.yHosts the 0x221E linux distro kernel.
https://git.0xinfinity.dev/distro/kernel.git/atom?h=linux-6.10.y2024-10-10T10:00:44Zpowerpc/vdso: Fix VDSO data access when running in a non-root time namespace2024-10-10T10:00:44ZChristophe Leroy2024-09-06T08:33:43Zurn:sha1:7270e5f957faa3e57878042984c1443486385c22
[ Upstream commit c73049389e58c01e2e3bbfae900c8daeee177191 ]
When running in a non-root time namespace, the global VDSO data page
is replaced by a dedicated namespace data page and the global data
page is mapped next to it. Detailed explanations can be found at
commit 660fd04f9317 ("lib/vdso: Prepare for time namespace support").
When it happens, __kernel_get_syscall_map and __kernel_get_tbfreq
and __kernel_sync_dicache don't work anymore because they read 0
instead of the data they need.
To address that, clock_mode has to be read. When it is set to
VDSO_CLOCKMODE_TIMENS, it means it is a dedicated namespace data page
and the global data is located on the following page.
Add a macro called get_realdatapage which reads clock_mode and add
PAGE_SIZE to the pointer provided by get_datapage macro when
clock_mode is equal to VDSO_CLOCKMODE_TIMENS. Use this new macro
instead of get_datapage macro except for time functions as they handle
it internally.
Fixes: 74205b3fc2ef ("powerpc/vdso: Add support for time namespaces")
Reported-by: Jason A. Donenfeld <Jason@zx2c4.com>
Closes: https://lore.kernel.org/all/ZtnYqZI-nrsNslwy@zx2c4.com/
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
powerpc/vdso: Fix __kernel_sync_dicache sequence with coherent icache2022-07-27T11:36:04ZNicholas Piggin2022-05-20T12:36:49Zurn:sha1:28f07fab26319dacc5675ae01dfc84d82122c59b
Processors with coherent icache require the sequence sync ; icbi ; isync
to entire store->execute coherency. icbi (to any address) must be
executed to ensure isync flushes the pipeline. See "POWER9 Processor
User's Manual, 4.6.2.2 Instruction Cache Block Invalidate (icbi)" for
details.
__kernel_sync_dicache is missing icbi for the coherent icache path.
Add it.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220520123649.258440-1-npiggin@gmail.com
powerpc/vdso: Merge vdso64 and vdso32 into a single directory2022-02-12T11:47:43ZChristophe Leroy2022-01-21T16:30:27Zurn:sha1:fd1feade75fb1a9275c39d76c5ccdbbbe6b37aa3
merge vdso64 into vdso32 and rename it vdso.
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/4dbe05cc130f6a0858d09ac72e436c373cb08b70.1642782130.git.christophe.leroy@csgroup.eu