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There are several spelling mistakes in kernel error messages. Fix them.
Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
Signed-off-by: Helge Deller <deller@gmx.de>
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Commit df24e1783e6e ("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: df24e1783e6e ("parisc: Add vDSO support")
Cc: <stable@vger.kernel.org> # 5.18+
Signed-off-by: Helge Deller <deller@gmx.de>
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Independend of the current graphics resolution, adjust the reported
graphics card memory size to the next 4MB boundary.
This fixes the fbtest program which expects a naturally aligned size.
Signed-off-by: Helge Deller <deller@gmx.de>
Cc: <stable@vger.kernel.org>
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The RISC-V patchwork instance on kernel.org has had some necromancy
performed on it & will be used going forward. The statuses that are
intended to be used are:
- New: No action has been taken yet
- Under Review: The maintainer is waiting for review comments from others
- Changes Requested: Either the maintainer or a reviewer requested
changes in the patch. The patch author is expected to submit a new
version
- Superseded: There's a new version of the patch available
- Not Applicable: The patch is not intended for the RISC-V tree
- Accepted: The patch has been applied
- Rejected: The patch has been rejected, with reasons stated in an
email
Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20221011160744.2167025-1-conor@kernel.org/
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
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Fix port I/O string accessors such as `insb', `outsb', etc. which use
the physical PCI port I/O address rather than the corresponding memory
mapping to get at the requested location, which in turn breaks at least
accesses made by our parport driver to a PCIe parallel port such as:
PCI parallel port detected: 1415:c118, I/O at 0x1000(0x1008), IRQ 20
parport0: PC-style at 0x1000 (0x1008), irq 20, using FIFO [PCSPP,TRISTATE,COMPAT,EPP,ECP]
causing a memory access fault:
Unable to handle kernel access to user memory without uaccess routines at virtual address 0000000000001008
Oops [#1]
Modules linked in:
CPU: 1 PID: 350 Comm: cat Not tainted 6.0.0-rc2-00283-g10d4879f9ef0-dirty #23
Hardware name: SiFive HiFive Unmatched A00 (DT)
epc : parport_pc_fifo_write_block_pio+0x266/0x416
ra : parport_pc_fifo_write_block_pio+0xb4/0x416
epc : ffffffff80542c3e ra : ffffffff80542a8c sp : ffffffd88899fc60
gp : ffffffff80fa2700 tp : ffffffd882b1e900 t0 : ffffffd883d0b000
t1 : ffffffffff000002 t2 : 4646393043330a38 s0 : ffffffd88899fcf0
s1 : 0000000000001000 a0 : 0000000000000010 a1 : 0000000000000000
a2 : ffffffd883d0a010 a3 : 0000000000000023 a4 : 00000000ffff8fbb
a5 : ffffffd883d0a001 a6 : 0000000100000000 a7 : ffffffc800000000
s2 : ffffffffff000002 s3 : ffffffff80d28880 s4 : ffffffff80fa1f50
s5 : 0000000000001008 s6 : 0000000000000008 s7 : ffffffd883d0a000
s8 : 0004000000000000 s9 : ffffffff80dc1d80 s10: ffffffd8807e4000
s11: 0000000000000000 t3 : 00000000000000ff t4 : 393044410a303930
t5 : 0000000000001000 t6 : 0000000000040000
status: 0000000200000120 badaddr: 0000000000001008 cause: 000000000000000f
[<ffffffff80543212>] parport_pc_compat_write_block_pio+0xfe/0x200
[<ffffffff8053bbc0>] parport_write+0x46/0xf8
[<ffffffff8050530e>] lp_write+0x158/0x2d2
[<ffffffff80185716>] vfs_write+0x8e/0x2c2
[<ffffffff80185a74>] ksys_write+0x52/0xc2
[<ffffffff80185af2>] sys_write+0xe/0x16
[<ffffffff80003770>] ret_from_syscall+0x0/0x2
---[ end trace 0000000000000000 ]---
For simplicity address the problem by adding PCI_IOBASE to the physical
address requested in the respective wrapper macros only, observing that
the raw accessors such as `__insb', `__outsb', etc. are not supposed to
be used other than by said macros. Remove the cast to `long' that is no
longer needed on `addr' now that it is used as an offset from PCI_IOBASE
and add parentheses around `addr' needed for predictable evaluation in
macro expansion. No need to make said adjustments in separate changes
given that current code is gravely broken and does not ever work.
Signed-off-by: Maciej W. Rozycki <macro@orcam.me.uk>
Fixes: fab957c11efe2 ("RISC-V: Atomic and Locking Code")
Cc: stable@vger.kernel.org # v4.15+
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/alpine.DEB.2.21.2209220223080.29493@angie.orcam.me.uk
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
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The PLIC specification does not describe the interrupt pendings bits as
read-write, only that they "can be read". To allow for retriggering of
interrupts (and the use of the irq debugfs interface) enable
HARDIRQS_SW_RESEND for RISC-V.
Link: https://github.com/riscv/riscv-plic-spec/blob/master/riscv-plic.adoc#interrupt-pending-bits
Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
Acked-by: Marc Zyngier <maz@kernel.org>
Acked-by: Palmer Dabbelt <palmer@rivosinc.com>
Tested-by: Palmer Dabbelt <palmer@rivosinc.com> # on QEMU
Reviewed-by: Björn Töpel <bjorn@kernel.org>
Link: https://lore.kernel.org/r/20220729111116.259146-1-conor.dooley@microchip.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
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These counters were part of the ISA when we froze the uABI, removing
them breaks userspace.
Link: https://lore.kernel.org/all/YxEhC%2FmDW1lFt36J@aurel32.net/
Fixes: e9991434596f ("RISC-V: Add perf platform driver based on SBI PMU extension")
Tested-by: Conor Dooley <conor.dooley@microchip.com>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20220928131807.30386-1-palmer@rivosinc.com
Cc: stable@vger.kernel.org
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
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Testing tools/testing/selftests/timens/vfork_exec.c got below
kernel log:
[ 6.838454] Unable to handle kernel access to user memory without uaccess routines at virtual address 0000000000000020
[ 6.842255] Oops [#1]
[ 6.842871] Modules linked in:
[ 6.844249] CPU: 1 PID: 64 Comm: vfork_exec Not tainted 6.0.0-rc3-rt15+ #8
[ 6.845861] Hardware name: riscv-virtio,qemu (DT)
[ 6.848009] epc : vdso_join_timens+0xd2/0x110
[ 6.850097] ra : vdso_join_timens+0xd2/0x110
[ 6.851164] epc : ffffffff8000635c ra : ffffffff8000635c sp : ff6000000181fbf0
[ 6.852562] gp : ffffffff80cff648 tp : ff60000000fdb700 t0 : 3030303030303030
[ 6.853852] t1 : 0000000000000030 t2 : 3030303030303030 s0 : ff6000000181fc40
[ 6.854984] s1 : ff60000001e6c000 a0 : 0000000000000010 a1 : ffffffff8005654c
[ 6.856221] a2 : 00000000ffffefff a3 : 0000000000000000 a4 : 0000000000000000
[ 6.858114] a5 : 0000000000000000 a6 : 0000000000000008 a7 : 0000000000000038
[ 6.859484] s2 : ff60000001e6c068 s3 : ff6000000108abb0 s4 : 0000000000000000
[ 6.860751] s5 : 0000000000001000 s6 : ffffffff8089dc40 s7 : ffffffff8089dc38
[ 6.862029] s8 : ffffffff8089dc30 s9 : ff60000000fdbe38 s10: 000000000000005e
[ 6.863304] s11: ffffffff80cc3510 t3 : ffffffff80d1112f t4 : ffffffff80d1112f
[ 6.864565] t5 : ffffffff80d11130 t6 : ff6000000181fa00
[ 6.865561] status: 0000000000000120 badaddr: 0000000000000020 cause: 000000000000000d
[ 6.868046] [<ffffffff8008dc94>] timens_commit+0x38/0x11a
[ 6.869089] [<ffffffff8008dde8>] timens_on_fork+0x72/0xb4
[ 6.870055] [<ffffffff80190096>] begin_new_exec+0x3c6/0x9f0
[ 6.871231] [<ffffffff801d826c>] load_elf_binary+0x628/0x1214
[ 6.872304] [<ffffffff8018ee7a>] bprm_execve+0x1f2/0x4e4
[ 6.873243] [<ffffffff8018f90c>] do_execveat_common+0x16e/0x1ee
[ 6.874258] [<ffffffff8018f9c8>] sys_execve+0x3c/0x48
[ 6.875162] [<ffffffff80003556>] ret_from_syscall+0x0/0x2
[ 6.877484] ---[ end trace 0000000000000000 ]---
This is because the mm->context.vdso_info is NULL in vfork case. From
another side, mm->context.vdso_info either points to vdso info
for RV64 or vdso info for compat, there's no need to bloat riscv's
mm_context_t, we can handle the difference when setup the additional
page for vdso.
Signed-off-by: Jisheng Zhang <jszhang@kernel.org>
Suggested-by: Palmer Dabbelt <palmer@rivosinc.com>
Fixes: 3092eb456375 ("riscv: compat: vdso: Add setup additional pages implementation")
Link: https://lore.kernel.org/r/20220924070737.3048-1-jszhang@kernel.org
Cc: stable@vger.kernel.org
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
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There are no standard CSR registers to provide cache information, the
way for RISC-V is to get this information from DT. sysconf syscall
could use them to get information of cache through AUX vector.
The result of 'getconf -a|grep -i cache' as follows:
LEVEL1_ICACHE_SIZE 32768
LEVEL1_ICACHE_ASSOC 2
LEVEL1_ICACHE_LINESIZE 64
LEVEL1_DCACHE_SIZE 32768
LEVEL1_DCACHE_ASSOC 4
LEVEL1_DCACHE_LINESIZE 64
LEVEL2_CACHE_SIZE 524288
LEVEL2_CACHE_ASSOC 8
LEVEL2_CACHE_LINESIZE 64
LEVEL3_CACHE_SIZE 4194304
LEVEL3_CACHE_ASSOC 16
LEVEL3_CACHE_LINESIZE 64
LEVEL4_CACHE_SIZE 0
LEVEL4_CACHE_ASSOC 0
LEVEL4_CACHE_LINESIZE 0
Signed-off-by: Greentime Hu <greentime.hu@sifive.com>
Signed-off-by: Zong Li <zong.li@sifive.com>
Suggested-by: Zong Li <zong.li@sifive.com>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20220913061817.22564-8-zong.li@sifive.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
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Define the macro for the register shifts, it could make the code be
more readable
Signed-off-by: Zong Li <zong.li@sifive.com>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20220913061817.22564-7-zong.li@sifive.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
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Use the pr_fmt() macro to prefix all the output with "CCACHE:"
to avoid having to write it out each time, or make a large diff
when the next change comes along.
Signed-off-by: Ben Dooks <ben.dooks@sifive.com>
Signed-off-by: Zong Li <zong.li@sifive.com>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20220913061817.22564-6-zong.li@sifive.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
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The driver prints out 6 lines on startup, which can easily be redcued
to two lines without losing any information.
Note, to make the types work better, uint64_t has been replaced with
ULL to make the unsigned long long match the format in the print
statement.
Signed-off-by: Ben Dooks <ben.dooks@sifive.com>
Signed-off-by: Zong Li <zong.li@sifive.com>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20220913061817.22564-5-zong.li@sifive.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
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Composable cache could be L2 or L3 cache, use 'cache-level' property of
device node to determine the level.
Signed-off-by: Zong Li <zong.li@sifive.com>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20220913061817.22564-4-zong.li@sifive.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
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Since composable cache may be L3 cache if there is a L2 cache, we should
use its original name composable cache to prevent confusion.
There are some new lines were generated due to adding the compatible
"sifive,ccache0" into ID table and indent requirement.
The sifive L2 has been renamed to sifive CCACHE, EDAC driver needs to
apply the change as well.
Signed-off-by: Greentime Hu <greentime.hu@sifive.com>
Signed-off-by: Zong Li <zong.li@sifive.com>
Co-developed-by: Zong Li <zong.li@sifive.com>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20220913061817.22564-3-zong.li@sifive.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
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Since composable cache may be L3 cache if private L2 cache exists, we
should use its original name Composable cache to prevent confusion.
Signed-off-by: Zong Li <zong.li@sifive.com>
Suggested-by: Conor Dooley <conor.dooley@microchip.com>
Suggested-by: Ben Dooks <ben.dooks@sifive.com>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20220913061817.22564-2-zong.li@sifive.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
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The '-t/-T' parameters seem to have been swapped:
-t/--trace[=file]: save the stopped trace
to [file|timerlat_trace.txt]
-T/--thread us: stop trace if the thread latency
is higher than the argument in us
Swap them back.
Signed-off-by: Pierre Gondois <pierre.gondois@arm.com>
Acked-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Link: https://lore.kernel.org/r/20221006084409.3882542-1-pierre.gondois@arm.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
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The devm_request_region() function does not return error pointers, it
returns NULL on error.
Fixes: 914d9b2711dd ("sunhme: switch to devres")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Sean Anderson <seanga2@gmail.com>
Reviewed-by: Rolf Eike Beer <eike-kernel@sf-tec.de>
Link: https://lore.kernel.org/r/Y0bWzJL8JknX8MUf@kili
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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The __prestera_nexthop_group_create() function returns NULL on error
and the prestera_nexthop_group_get() returns error pointers. Fix these
two checks.
Fixes: 0a23ae237171 ("net: marvell: prestera: Add router nexthops ABI")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Link: https://lore.kernel.org/r/Y0bWq+7DoKK465z8@kili
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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syzbot found that kcm_tx_work() could crash [1] in:
/* Primarily for SOCK_SEQPACKET sockets */
if (likely(sk->sk_socket) &&
test_bit(SOCK_NOSPACE, &sk->sk_socket->flags)) {
<<*>> clear_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
sk->sk_write_space(sk);
}
I think the reason is that another thread might concurrently
run in kcm_release() and call sock_orphan(sk) while sk is not
locked. kcm_tx_work() find sk->sk_socket being NULL.
[1]
BUG: KASAN: null-ptr-deref in instrument_atomic_write include/linux/instrumented.h:86 [inline]
BUG: KASAN: null-ptr-deref in clear_bit include/asm-generic/bitops/instrumented-atomic.h:41 [inline]
BUG: KASAN: null-ptr-deref in kcm_tx_work+0xff/0x160 net/kcm/kcmsock.c:742
Write of size 8 at addr 0000000000000008 by task kworker/u4:3/53
CPU: 0 PID: 53 Comm: kworker/u4:3 Not tainted 5.19.0-rc3-next-20220621-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: kkcmd kcm_tx_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
kasan_report+0xbe/0x1f0 mm/kasan/report.c:495
check_region_inline mm/kasan/generic.c:183 [inline]
kasan_check_range+0x13d/0x180 mm/kasan/generic.c:189
instrument_atomic_write include/linux/instrumented.h:86 [inline]
clear_bit include/asm-generic/bitops/instrumented-atomic.h:41 [inline]
kcm_tx_work+0xff/0x160 net/kcm/kcmsock.c:742
process_one_work+0x996/0x1610 kernel/workqueue.c:2289
worker_thread+0x665/0x1080 kernel/workqueue.c:2436
kthread+0x2e9/0x3a0 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:302
</TASK>
Fixes: ab7ac4eb9832 ("kcm: Kernel Connection Multiplexor module")
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Tom Herbert <tom@herbertland.com>
Link: https://lore.kernel.org/r/20221012133412.519394-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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Eric Dumazet reported a use-after-free related to the per-netns ehash
series. [0]
When we create a TCP socket from userspace, the socket always holds a
refcnt of the netns. This guarantees that a reqsk timer is always fired
before netns dismantle. Each reqsk has a refcnt of its listener, so the
listener is not freed before the reqsk, and the net is not freed before
the listener as well.
OTOH, when in-kernel users create a TCP socket, it might not hold a refcnt
of its netns. Thus, a reqsk timer can be fired after the netns dismantle
and access freed per-netns ehash.
To avoid the use-after-free, we need to clean up TCP_NEW_SYN_RECV sockets
in inet_twsk_purge() if the netns uses a per-netns ehash.
[0]: https://lore.kernel.org/netdev/CANn89iLXMup0dRD_Ov79Xt8N9FM0XdhCHEN05sf3eLwxKweM6w@mail.gmail.com/
BUG: KASAN: use-after-free in tcp_or_dccp_get_hashinfo
include/net/inet_hashtables.h:181 [inline]
BUG: KASAN: use-after-free in reqsk_queue_unlink+0x320/0x350
net/ipv4/inet_connection_sock.c:913
Read of size 8 at addr ffff88807545bd80 by task syz-executor.2/8301
CPU: 1 PID: 8301 Comm: syz-executor.2 Not tainted
6.0.0-syzkaller-02757-gaf7d23f9d96a #0
Hardware name: Google Google Compute Engine/Google Compute Engine,
BIOS Google 09/22/2022
Call Trace:
<IRQ>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
print_address_description mm/kasan/report.c:317 [inline]
print_report.cold+0x2ba/0x719 mm/kasan/report.c:433
kasan_report+0xb1/0x1e0 mm/kasan/report.c:495
tcp_or_dccp_get_hashinfo include/net/inet_hashtables.h:181 [inline]
reqsk_queue_unlink+0x320/0x350 net/ipv4/inet_connection_sock.c:913
inet_csk_reqsk_queue_drop net/ipv4/inet_connection_sock.c:927 [inline]
inet_csk_reqsk_queue_drop_and_put net/ipv4/inet_connection_sock.c:939 [inline]
reqsk_timer_handler+0x724/0x1160 net/ipv4/inet_connection_sock.c:1053
call_timer_fn+0x1a0/0x6b0 kernel/time/timer.c:1474
expire_timers kernel/time/timer.c:1519 [inline]
__run_timers.part.0+0x674/0xa80 kernel/time/timer.c:1790
__run_timers kernel/time/timer.c:1768 [inline]
run_timer_softirq+0xb3/0x1d0 kernel/time/timer.c:1803
__do_softirq+0x1d0/0x9c8 kernel/softirq.c:571
invoke_softirq kernel/softirq.c:445 [inline]
__irq_exit_rcu+0x123/0x180 kernel/softirq.c:650
irq_exit_rcu+0x5/0x20 kernel/softirq.c:662
sysvec_apic_timer_interrupt+0x93/0xc0 arch/x86/kernel/apic/apic.c:1107
</IRQ>
Fixes: d1e5e6408b30 ("tcp: Introduce optional per-netns ehash.")
Reported-by: syzbot <syzkaller@googlegroups.com>
Reported-by: Eric Dumazet <edumazet@google.com>
Suggested-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/20221012145036.74960-1-kuniyu@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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Pantelis has not been active in recent years so no need to maintain
a separate entry for device tree overlays.
Signed-off-by: Frank Rowand <frank.rowand@sony.com>
Link: https://lore.kernel.org/r/20221012220548.4163865-1-frowand.list@gmail.com
Signed-off-by: Rob Herring <robh@kernel.org>
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The t-head variant of page-based memory types should also check first
for the enabled kernel config option.
Fixes: a35707c3d850 ("riscv: add memory-type errata for T-Head")
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: Guo Ren <guoren@kernel.org>
Link: https://lore.kernel.org/r/20220905111027.2463297-6-heiko@sntech.de
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
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Using the appropriate BIT macro makes the code better readable.
Suggested-by: Conor Dooley <conor.dooley@microchip.com>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20220905111027.2463297-5-heiko@sntech.de
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
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Using the appropriate BIT macro makes the code better readable.
Suggested-by: Conor Dooley <conor.dooley@microchip.com>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Reviewed-by: Guo Ren <guoren@kernel.org>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Link: https://lore.kernel.org/r/20220905111027.2463297-4-heiko@sntech.de
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
|
|
Wrapping things in #ifdefs makes the code harder to read
while we also have IS_ENABLED() macros to do this in regular code
and the extension detection is not _that_ runtime critical.
So define a stub for riscv_noncoherent_supported() in the
non-CONFIG_RISCV_DMA_NONCOHERENT case and move the code to
us IS_ENABLED.
Suggested-by: Conor Dooley <conor.dooley@microchip.com>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Reviewed-by: Guo Ren <guoren@kernel.org>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Link: https://lore.kernel.org/r/20220905111027.2463297-3-heiko@sntech.de
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
|
|
For better readability (and compile time coverage) use IS_ENABLED
instead of ifdef and drop the new unneeded switch statement.
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Reviewed-by: Guo Ren <guoren@kernel.org>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Link: https://lore.kernel.org/r/20220905111027.2463297-2-heiko@sntech.de
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
|
|
lld since llvm:6611d58f5bbc ("[ELF] Relax R_RISCV_ALIGN"), which will be
included in the 15.0.0 release, has implemented some RISC-V linker
relaxation. -mno-relax is no longer needed in
KBUILD_CFLAGS/KBUILD_AFLAGS to suppress R_RISCV_ALIGN which older lld
can not handle:
ld.lld: error: capability.c:(.fixup+0x0): relocation R_RISCV_ALIGN
requires unimplemented linker relaxation; recompile with -mno-relax
but the .o is already compiled with -mno-relax
Signed-off-by: Fangrui Song <maskray@google.com>
Link: https://lore.kernel.org/r/20220710071117.446112-1-maskray@google.com/
Link: https://lore.kernel.org/r/20220918092933.19943-1-palmer@rivosinc.com
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Tested-by: Nick Desaulniers <ndesaulniers@google.com>
Tested-by: Nathan Chancellor <nathan@kernel.org>
Tested-by: Conor Dooley <conor.dooley@microchip.com>
Cc: stable@vger.kernel.org
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
|
|
Zhu Lingshan has been writing and reviewing ifcvf patches for
a while now, add as reviewer.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Zhu Lingshan <lingshan.zhu@intel.com>
Acked-by: Jason Wang <jasowang@redhat.com>
|
|
commit 71491c54eafa ("virtio_pci: don't try to use intxif pin is zero")
breaks virtio_pci on powerpc, when running as a qemu guest.
vp_find_vqs() bails out because pci_dev->pin == 0.
But pci_dev->irq is populated correctly, so vp_find_vqs_intx() would
succeed if we called it - which is what the code used to do.
This seems to happen because pci_dev->pin is not populated in
pci_assign_irq(). A PCI core bug? Maybe.
However Linus said:
I really think that that is basically the only time you should use
that 'pci_dev->pin' thing: it basically exists not for "does this
device have an IRQ", but for "what is the routing of this irq on this
device".
and
The correct way to check for "no irq" doesn't use NO_IRQ at all, it just does
if (dev->irq) ...
so let's just check irq and be done with it.
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Reported-by: Michael Ellerman <mpe@ellerman.id.au>
Fixes: 71491c54eafa ("virtio_pci: don't try to use intxif pin is zero")
Cc: "Angus Chen" <angus.chen@jaguarmicro.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Tested-by: Michael Ellerman <mpe@ellerman.id.au>
Acked-by: Jason Wang <jasowang@redhat.com>
Message-Id: <20221012220312.308522-1-mst@redhat.com>
|
|
The recently moved dtl code must be compiled-in if
CONFIG_VIRT_CPU_ACCOUNTING_NATIVE=y even if CONFIG_DTL=n.
Fixes: 6ba5aa541aaa0 ("powerpc/pseries: Move dtl scanning and steal time accounting to pseries platform")
Reported-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20221013073131.1485742-1-npiggin@gmail.com
|
|
It's possible for an interrupt returning to an irqs-disabled context to
lose a pending soft-masked irq because it branches to part of the exit
code for irqs-enabled contexts, which is meant to clear only the
PACA_IRQS_HARD_DIS flag from PACAIRQHAPPENED by zeroing the byte. This
just looks like a simple thinko from a recent commit (if there was no
hard mask pending, there would be no reason to clear it anyway).
This also adds comment to the code that actually does need to clear the
flag.
Fixes: e485f6c751e0a ("powerpc/64/interrupt: Fix return to masked context after hard-mask irq becomes pending")
Reported-by: Sachin Sant <sachinp@linux.ibm.com>
Reported-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20221013064418.1311104-1-npiggin@gmail.com
|
|
I don't think we can actually die() without a regs pointer, but the
compiler was warning about a NULL check after a dereference. It seems
prudent to just avoid the possibly-NULL dereference, given that when
die()ing the system is already toast so who knows how we got there.
Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20220920200037.6727-1-palmer@rivosinc.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
|
|
kmap_to_page() is used to get the page for a virtual address which may
be kmap'ed. Unfortunately, kmap_local_page() stores mappings in a
thread local array separate from kmap(). These mappings were not
checked by the call.
Check the kmap_local_page() mappings and return the page if found.
Because it is intended to remove kmap_to_page() add a warn on once to
the kmap checks to flag potential issues early.
NOTE Due to 32bit x86 use of kmap local in iomap atmoic, KMAP_LOCAL does
not require HIGHMEM to be set. Therefore the support calls required a
new KMAP_LOCAL section to fix 0day build errors.
[akpm@linux-foundation.org: fix warning]
Link: https://lkml.kernel.org/r/20221006040555.1502679-1-ira.weiny@intel.com
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
Reported-by: Al Viro <viro@zeniv.linux.org.uk>
Reported-by: kernel test robot <lkp@intel.com>
Cc: "Fabio M. De Francesco" <fmdefrancesco@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
PGFREE and PGALLOC represent the number of freed and allocated pages. So
the page order must be considered.
Link: https://lkml.kernel.org/r/20221006101540.40686-1-laoar.shao@gmail.com
Fixes: 44042b449872 ("mm/page_alloc: allow high-order pages to be stored on the per-cpu lists")
Signed-off-by: Yafang Shao <laoar.shao@gmail.com>
Acked-by: Mel Gorman <mgorman@techsingularity.net>
Reviewed-by: Miaohe Lin <linmiaohe@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
It's not obvious why we had a write check for each of the missing
messages, especially when it should be a locking op. Add a rich comment
for that, and also try to explain its good side and limitations, so that
if someone hit it again for either a bug or a different glibc impl
there'll be some clue to start with.
Link: https://lkml.kernel.org/r/20221004193400.110155-4-peterx@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Nadav Amit <nadav.amit@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
After hugetlb_pte_stable() introduced, we can also rewrite the migration
race condition against page allocation to use the new helper too.
Link: https://lkml.kernel.org/r/20221004193400.110155-3-peterx@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Nadav Amit <nadav.amit@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
Patch series "mm/hugetlb: Fix selftest failures with write check", v3.
Currently akpm mm-unstable fails with uffd hugetlb private mapping test
randomly on a write check.
The initial bisection of that points to the recent pmd unshare series, but
it turns out there's no direction relationship with the series but only
some timing change caused the race to start trigger.
The race should be fixed in patch 1. Patch 2 is a trivial cleanup on the
similar race with hugetlb migrations, patch 3 comment on the write check
so when anyone read it again it'll be clear why it's there.
This patch (of 3):
After the recent rework patchset of hugetlb locking on pmd sharing,
kselftest for userfaultfd sometimes fails on hugetlb private tests with
unexpected write fault checks.
It turns out there's nothing wrong within the locking series regarding
this matter, but it could have changed the timing of threads so it can
trigger an old bug.
The real bug is when we call hugetlb_no_page() we're not with the pgtable
lock. It means we're reading the pte values lockless. It's perfectly
fine in most cases because before we do normal page allocations we'll take
the lock and check pte_same() again. However before that, there are
actually two paths on userfaultfd missing/minor handling that may directly
move on with the fault process without checking the pte values.
It means for these two paths we may be generating an uffd message based on
an unstable pte, while an unstable pte can legally be anything as long as
the modifier holds the pgtable lock.
One example, which is also what happened in the failing kselftest and
caused the test failure, is that for private mappings wr-protection
changes can happen on one page. While hugetlb_change_protection()
generally requires pte being cleared before being changed, then there can
be a race condition like:
thread 1 thread 2
-------- --------
UFFDIO_WRITEPROTECT hugetlb_fault
hugetlb_change_protection
pgtable_lock()
huge_ptep_modify_prot_start
pte==NULL
hugetlb_no_page
generate uffd missing event
even if page existed!!
huge_ptep_modify_prot_commit
pgtable_unlock()
Fix this by rechecking the pte after pgtable lock for both userfaultfd
missing & minor fault paths.
This bug should have been around starting from uffd hugetlb introduced, so
attaching a Fixes to the commit. Also attach another Fixes to the minor
support commit for easier tracking.
Note that userfaultfd is actually fine with false positives (e.g. caused
by pte changed), but not wrong logical events (e.g. caused by reading a
pte during changing). The latter can confuse the userspace, so the
strictness is very much preferred. E.g., MISSING event should never
happen on the page after UFFDIO_COPY has correctly installed the page and
returned.
Link: https://lkml.kernel.org/r/20221004193400.110155-1-peterx@redhat.com
Link: https://lkml.kernel.org/r/20221004193400.110155-2-peterx@redhat.com
Fixes: 1a1aad8a9b7b ("userfaultfd: hugetlbfs: add userfaultfd hugetlb hook")
Fixes: 7677f7fd8be7 ("userfaultfd: add minor fault registration mode")
Signed-off-by: Peter Xu <peterx@redhat.com>
Co-developed-by: Mike Kravetz <mike.kravetz@oracle.com>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: Nadav Amit <nadav.amit@gmail.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
Currently zram will adjust its fops to a version which does not contain
rw_page when a backing device has been assigned. This is done to prevent
upper layers from assuming a synchronous operation when a page may have
been written back. This forces every operation through bio which has
overhead associated with bio_alloc/frees.
The code can be simplified to always expose an rw_page method and only in
the rare event that a page is written back we instead will return
-EOPNOTSUPP forcing the upper layer to fallback to bio.
Link: https://lkml.kernel.org/r/20221003144832.2906610-1-bgeffon@google.com
Signed-off-by: Brian Geffon <bgeffon@google.com>
Reviewed-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Nitin Gupta <ngupta@vflare.org>
Cc: Rom Lemarchand <romlem@google.com>
Cc: Suleiman Souhlal <suleiman@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
Currently, the implementation of update_mmu_tlb() is empty if
__HAVE_ARCH_UPDATE_MMU_TLB is not defined. Then if two threads
concurrently fault at the same page, the second thread that did not win
the race will give up and do nothing. In the LoongArch architecture, this
second thread will trigger another fault, and only updates its local TLB.
Instead of triggering another fault, it's better to implement
update_mmu_tlb() to directly update the local TLB of the second thread.
Just do it.
Link: https://lkml.kernel.org/r/20220929112318.32393-3-zhengqi.arch@bytedance.com
Signed-off-by: Qi Zheng <zhengqi.arch@bytedance.com>
Suggested-by: Bibo Mao <maobibo@loongson.cn>
Acked-by: Huacai Chen <chenhuacai@loongson.cn>
Cc: Chris Zankel <chris@zankel.net>
Cc: David Hildenbrand <david@redhat.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Muchun Song <songmuchun@bytedance.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
As message in commit 7df676974359 ("mm/memory.c: Update local TLB if PTE
entry exists") said, we should update local TLB only on the second thread.
So in the do_anonymous_page() here, we should use update_mmu_tlb()
instead of update_mmu_cache() on the second thread.
As David pointed out, this is a performance improvement, not a
correctness fix.
Link: https://lkml.kernel.org/r/20220929112318.32393-2-zhengqi.arch@bytedance.com
Signed-off-by: Qi Zheng <zhengqi.arch@bytedance.com>
Reviewed-by: Muchun Song <songmuchun@bytedance.com>
Acked-by: David Hildenbrand <david@redhat.com>
Cc: Bibo Mao <maobibo@loongson.cn>
Cc: Chris Zankel <chris@zankel.net>
Cc: Huacai Chen <chenhuacai@loongson.cn>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
GCC's -Warray-bounds option detects out-of-bounds accesses to
statically-sized allocations in krealloc out-of-bounds tests.
Use OPTIMIZER_HIDE_VAR to suppress the warning.
Also change kmalloc_memmove_invalid_size to use OPTIMIZER_HIDE_VAR
instead of a volatile variable.
Link: https://lkml.kernel.org/r/e94399242d32e00bba6fd0d9ec4c897f188128e8.1664215688.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reported-by: kernel test robot <lkp@intel.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Marco Elver <elver@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
Link: https://lkml.kernel.org/r/a73cf109de0224cfd118d22be58ddebac3ae2897.1664366292.git-series.apopple@nvidia.com
Signed-off-by: Alistair Popple <apopple@nvidia.com>
Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: Ralph Campbell <rcampbell@nvidia.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Alex Sierra <alex.sierra@amd.com>
Cc: Felix Kuehling <Felix.Kuehling@amd.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: Ben Skeggs <bskeggs@redhat.com>
Cc: Christian König <christian.koenig@amd.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: "Huang, Ying" <ying.huang@intel.com>
Cc: Lyude Paul <lyude@redhat.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Yang Shi <shy828301@gmail.com>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
When the module is unloaded or a GPU is unbound from the module it is
possible for device private pages to still be mapped in currently running
processes. This can lead to a hangs and RCU stall warnings when unbinding
the device as memunmap_pages() will wait in an uninterruptible state until
all device pages have been freed which may never happen.
Fix this by migrating device mappings back to normal CPU memory prior to
freeing the GPU memory chunks and associated device private pages.
Link: https://lkml.kernel.org/r/66277601fb8fda9af408b33da9887192bf895bda.1664366292.git-series.apopple@nvidia.com
Signed-off-by: Alistair Popple <apopple@nvidia.com>
Cc: Lyude Paul <lyude@redhat.com>
Cc: Ben Skeggs <bskeggs@redhat.com>
Cc: Ralph Campbell <rcampbell@nvidia.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: Alex Sierra <alex.sierra@amd.com>
Cc: Christian König <christian.koenig@amd.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Felix Kuehling <Felix.Kuehling@amd.com>
Cc: "Huang, Ying" <ying.huang@intel.com>
Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Yang Shi <shy828301@gmail.com>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
nouveau_dmem_fault_copy_one() is used during handling of CPU faults via
the migrate_to_ram() callback and is used to copy data from GPU to CPU
memory. It is currently specific to fault handling, however a future
patch implementing eviction of data during teardown needs similar
functionality.
Refactor out the core functionality so that it is not specific to fault
handling.
Link: https://lkml.kernel.org/r/20573d7b4e641a78fde9935f948e64e71c9e709e.1664366292.git-series.apopple@nvidia.com
Signed-off-by: Alistair Popple <apopple@nvidia.com>
Reviewed-by: Lyude Paul <lyude@redhat.com>
Cc: Ben Skeggs <bskeggs@redhat.com>
Cc: Ralph Campbell <rcampbell@nvidia.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: Alex Sierra <alex.sierra@amd.com>
Cc: Christian König <christian.koenig@amd.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Felix Kuehling <Felix.Kuehling@amd.com>
Cc: "Huang, Ying" <ying.huang@intel.com>
Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Yang Shi <shy828301@gmail.com>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
Device drivers can use the migrate_vma family of functions to migrate
existing private anonymous mappings to device private pages. These pages
are backed by memory on the device with drivers being responsible for
copying data to and from device memory.
Device private pages are freed via the pgmap->page_free() callback when
they are unmapped and their refcount drops to zero. Alternatively they
may be freed indirectly via migration back to CPU memory in response to a
pgmap->migrate_to_ram() callback called whenever the CPU accesses an
address mapped to a device private page.
In other words drivers cannot control the lifetime of data allocated on
the devices and must wait until these pages are freed from userspace.
This causes issues when memory needs to reclaimed on the device, either
because the device is going away due to a ->release() callback or because
another user needs to use the memory.
Drivers could use the existing migrate_vma functions to migrate data off
the device. However this would require them to track the mappings of each
page which is both complicated and not always possible. Instead drivers
need to be able to migrate device pages directly so they can free up
device memory.
To allow that this patch introduces the migrate_device family of functions
which are functionally similar to migrate_vma but which skips the initial
lookup based on mapping.
Link: https://lkml.kernel.org/r/868116aab70b0c8ee467d62498bb2cf0ef907295.1664366292.git-series.apopple@nvidia.com
Signed-off-by: Alistair Popple <apopple@nvidia.com>
Cc: "Huang, Ying" <ying.huang@intel.com>
Cc: Zi Yan <ziy@nvidia.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Yang Shi <shy828301@gmail.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Ralph Campbell <rcampbell@nvidia.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: Alex Sierra <alex.sierra@amd.com>
Cc: Ben Skeggs <bskeggs@redhat.com>
Cc: Christian König <christian.koenig@amd.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Felix Kuehling <Felix.Kuehling@amd.com>
Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: Lyude Paul <lyude@redhat.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
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migrate_device_coherent_page() reuses the existing migrate_vma family of
functions to migrate a specific page without providing a valid mapping or
vma. This looks a bit odd because it means we are calling migrate_vma_*()
without setting a valid vma, however it was considered acceptable at the
time because the details were internal to migrate_device.c and there was
only a single user.
One of the reasons the details could be kept internal was that this was
strictly for migrating device coherent memory. Such memory can be copied
directly by the CPU without intervention from a driver. However this
isn't true for device private memory, and a future change requires similar
functionality for device private memory. So refactor the code into
something more sensible for migrating device memory without a vma.
Link: https://lkml.kernel.org/r/c7b2ff84e9b33d022cf4a40f87d051f281a16d8f.1664366292.git-series.apopple@nvidia.com
Signed-off-by: Alistair Popple <apopple@nvidia.com>
Cc: "Huang, Ying" <ying.huang@intel.com>
Cc: Zi Yan <ziy@nvidia.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Yang Shi <shy828301@gmail.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Ralph Campbell <rcampbell@nvidia.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: Alex Sierra <alex.sierra@amd.com>
Cc: Ben Skeggs <bskeggs@redhat.com>
Cc: Christian König <christian.koenig@amd.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Felix Kuehling <Felix.Kuehling@amd.com>
Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: Lyude Paul <lyude@redhat.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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ZONE_DEVICE pages have a struct dev_pagemap which is allocated by a
driver. When the struct page is first allocated by the kernel in
memremap_pages() a reference is taken on the associated pagemap to ensure
it is not freed prior to the pages being freed.
Prior to 27674ef6c73f ("mm: remove the extra ZONE_DEVICE struct page
refcount") pages were considered free and returned to the driver when the
reference count dropped to one. However the pagemap reference was not
dropped until the page reference count hit zero. This would occur as part
of the final put_page() in memunmap_pages() which would wait for all pages
to be freed prior to returning.
When the extra refcount was removed the pagemap reference was no longer
being dropped in put_page(). Instead memunmap_pages() was changed to
explicitly drop the pagemap references. This means that memunmap_pages()
can complete even though pages are still mapped by the kernel which can
lead to kernel crashes, particularly if a driver frees the pagemap.
To fix this drivers should take a pagemap reference when allocating the
page. This reference can then be returned when the page is freed.
Link: https://lkml.kernel.org/r/12d155ec727935ebfbb4d639a03ab374917ea51b.1664366292.git-series.apopple@nvidia.com
Signed-off-by: Alistair Popple <apopple@nvidia.com>
Fixes: 27674ef6c73f ("mm: remove the extra ZONE_DEVICE struct page refcount")
Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: Felix Kuehling <Felix.Kuehling@amd.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: Christian König <christian.koenig@amd.com>
Cc: Ben Skeggs <bskeggs@redhat.com>
Cc: Lyude Paul <lyude@redhat.com>
Cc: Ralph Campbell <rcampbell@nvidia.com>
Cc: Alex Sierra <alex.sierra@amd.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: "Huang, Ying" <ying.huang@intel.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Yang Shi <shy828301@gmail.com>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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Since 27674ef6c73f ("mm: remove the extra ZONE_DEVICE struct page
refcount") device private pages have no longer had an extra reference
count when the page is in use. However before handing them back to the
owning device driver we add an extra reference count such that free pages
have a reference count of one.
This makes it difficult to tell if a page is free or not because both free
and in use pages will have a non-zero refcount. Instead we should return
pages to the drivers page allocator with a zero reference count. Kernel
code can then safely use kernel functions such as get_page_unless_zero().
Link: https://lkml.kernel.org/r/cf70cf6f8c0bdb8aaebdbfb0d790aea4c683c3c6.1664366292.git-series.apopple@nvidia.com
Signed-off-by: Alistair Popple <apopple@nvidia.com>
Acked-by: Felix Kuehling <Felix.Kuehling@amd.com>
Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: Christian König <christian.koenig@amd.com>
Cc: Ben Skeggs <bskeggs@redhat.com>
Cc: Lyude Paul <lyude@redhat.com>
Cc: Ralph Campbell <rcampbell@nvidia.com>
Cc: Alex Sierra <alex.sierra@amd.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: "Huang, Ying" <ying.huang@intel.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Yang Shi <shy828301@gmail.com>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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Patch series "Fix several device private page reference counting issues",
v2
This series aims to fix a number of page reference counting issues in
drivers dealing with device private ZONE_DEVICE pages. These result in
use-after-free type bugs, either from accessing a struct page which no
longer exists because it has been removed or accessing fields within the
struct page which are no longer valid because the page has been freed.
During normal usage it is unlikely these will cause any problems. However
without these fixes it is possible to crash the kernel from userspace.
These crashes can be triggered either by unloading the kernel module or
unbinding the device from the driver prior to a userspace task exiting.
In modules such as Nouveau it is also possible to trigger some of these
issues by explicitly closing the device file-descriptor prior to the task
exiting and then accessing device private memory.
This involves some minor changes to both PowerPC and AMD GPU code.
Unfortunately I lack hardware to test either of those so any help there
would be appreciated. The changes mimic what is done in for both Nouveau
and hmm-tests though so I doubt they will cause problems.
This patch (of 8):
When the CPU tries to access a device private page the migrate_to_ram()
callback associated with the pgmap for the page is called. However no
reference is taken on the faulting page. Therefore a concurrent migration
of the device private page can free the page and possibly the underlying
pgmap. This results in a race which can crash the kernel due to the
migrate_to_ram() function pointer becoming invalid. It also means drivers
can't reliably read the zone_device_data field because the page may have
been freed with memunmap_pages().
Close the race by getting a reference on the page while holding the ptl to
ensure it has not been freed. Unfortunately the elevated reference count
will cause the migration required to handle the fault to fail. To avoid
this failure pass the faulting page into the migrate_vma functions so that
if an elevated reference count is found it can be checked to see if it's
expected or not.
[mpe@ellerman.id.au: fix build]
Link: https://lkml.kernel.org/r/87fsgbf3gh.fsf@mpe.ellerman.id.au
Link: https://lkml.kernel.org/r/cover.60659b549d8509ddecafad4f498ee7f03bb23c69.1664366292.git-series.apopple@nvidia.com
Link: https://lkml.kernel.org/r/d3e813178a59e565e8d78d9b9a4e2562f6494f90.1664366292.git-series.apopple@nvidia.com
Signed-off-by: Alistair Popple <apopple@nvidia.com>
Acked-by: Felix Kuehling <Felix.Kuehling@amd.com>
Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Ralph Campbell <rcampbell@nvidia.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Lyude Paul <lyude@redhat.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: Alex Sierra <alex.sierra@amd.com>
Cc: Ben Skeggs <bskeggs@redhat.com>
Cc: Christian König <christian.koenig@amd.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: "Huang, Ying" <ying.huang@intel.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Yang Shi <shy828301@gmail.com>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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In many places we can use damon_sz_region() to instead of "r->ar.end -
r->ar.start".
Link: https://lkml.kernel.org/r/20220927001946.85375-2-xhao@linux.alibaba.com
Signed-off-by: Xin Hao <xhao@linux.alibaba.com>
Suggested-by: SeongJae Park <sj@kernel.org>
Reviewed-by: SeongJae Park <sj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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