<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux.git/arch/riscv/include/asm, branch v5.4.264</title>
<subtitle>Clone of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git</subtitle>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/'/>
<entry>
<title>riscv: uaccess: fix type of 0 variable on error in get_user()</title>
<updated>2023-01-18T10:41:59+00:00</updated>
<author>
<name>Ben Dooks</name>
<email>ben-linux@fluff.org</email>
</author>
<published>2022-12-29T17:05:45+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=1464feb5b6fa7bd415fab95d21de1405885e8834'/>
<id>1464feb5b6fa7bd415fab95d21de1405885e8834</id>
<content type='text'>
commit b9b916aee6715cd7f3318af6dc360c4729417b94 upstream.

If the get_user(x, ptr) has x as a pointer, then the setting
of (x) = 0 is going to produce the following sparse warning,
so fix this by forcing the type of 'x' when access_ok() fails.

fs/aio.c:2073:21: warning: Using plain integer as NULL pointer

Signed-off-by: Ben Dooks &lt;ben-linux@fluff.org&gt;
Reviewed-by: Palmer Dabbelt &lt;palmer@rivosinc.com&gt;
Link: https://lore.kernel.org/r/20221229170545.718264-1-ben-linux@fluff.org
Cc: stable@vger.kernel.org
Signed-off-by: Palmer Dabbelt &lt;palmer@rivosinc.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit b9b916aee6715cd7f3318af6dc360c4729417b94 upstream.

If the get_user(x, ptr) has x as a pointer, then the setting
of (x) = 0 is going to produce the following sparse warning,
so fix this by forcing the type of 'x' when access_ok() fails.

fs/aio.c:2073:21: warning: Using plain integer as NULL pointer

Signed-off-by: Ben Dooks &lt;ben-linux@fluff.org&gt;
Reviewed-by: Palmer Dabbelt &lt;palmer@rivosinc.com&gt;
Link: https://lore.kernel.org/r/20221229170545.718264-1-ben-linux@fluff.org
Cc: stable@vger.kernel.org
Signed-off-by: Palmer Dabbelt &lt;palmer@rivosinc.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>RISC-V: Make port I/O string accessors actually work</title>
<updated>2022-10-26T11:22:15+00:00</updated>
<author>
<name>Maciej W. Rozycki</name>
<email>macro@orcam.me.uk</email>
</author>
<published>2022-09-22T21:56:06+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=2c60db6869fe5213471fcf4fe5704dc29da8b5ee'/>
<id>2c60db6869fe5213471fcf4fe5704dc29da8b5ee</id>
<content type='text'>
commit 9cc205e3c17d5716da7ebb7fa0c985555e95d009 upstream.

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
[&lt;ffffffff80543212&gt;] parport_pc_compat_write_block_pio+0xfe/0x200
[&lt;ffffffff8053bbc0&gt;] parport_write+0x46/0xf8
[&lt;ffffffff8050530e&gt;] lp_write+0x158/0x2d2
[&lt;ffffffff80185716&gt;] vfs_write+0x8e/0x2c2
[&lt;ffffffff80185a74&gt;] ksys_write+0x52/0xc2
[&lt;ffffffff80185af2&gt;] sys_write+0xe/0x16
[&lt;ffffffff80003770&gt;] 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 &lt;macro@orcam.me.uk&gt;
Fixes: fab957c11efe2 ("RISC-V: Atomic and Locking Code")
Cc: stable@vger.kernel.org # v4.15+
Reviewed-by: Arnd Bergmann &lt;arnd@arndb.de&gt;
Link: https://lore.kernel.org/r/alpine.DEB.2.21.2209220223080.29493@angie.orcam.me.uk
Signed-off-by: Palmer Dabbelt &lt;palmer@rivosinc.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 9cc205e3c17d5716da7ebb7fa0c985555e95d009 upstream.

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
[&lt;ffffffff80543212&gt;] parport_pc_compat_write_block_pio+0xfe/0x200
[&lt;ffffffff8053bbc0&gt;] parport_write+0x46/0xf8
[&lt;ffffffff8050530e&gt;] lp_write+0x158/0x2d2
[&lt;ffffffff80185716&gt;] vfs_write+0x8e/0x2c2
[&lt;ffffffff80185a74&gt;] ksys_write+0x52/0xc2
[&lt;ffffffff80185af2&gt;] sys_write+0xe/0x16
[&lt;ffffffff80003770&gt;] 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 &lt;macro@orcam.me.uk&gt;
Fixes: fab957c11efe2 ("RISC-V: Atomic and Locking Code")
Cc: stable@vger.kernel.org # v4.15+
Reviewed-by: Arnd Bergmann &lt;arnd@arndb.de&gt;
Link: https://lore.kernel.org/r/alpine.DEB.2.21.2209220223080.29493@angie.orcam.me.uk
Signed-off-by: Palmer Dabbelt &lt;palmer@rivosinc.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>riscv: Less inefficient gcc tishift helpers (and export their symbols)</title>
<updated>2022-06-22T12:11:24+00:00</updated>
<author>
<name>Olof Johansson</name>
<email>olof@lixom.net</email>
</author>
<published>2019-12-17T04:06:31+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=1a48a41f14222177365fd3cf2049705f39281eaa'/>
<id>1a48a41f14222177365fd3cf2049705f39281eaa</id>
<content type='text'>
commit fc585d4a5cf614727f64d86550b794bcad29d5c3 upstream.

The existing __lshrti3 was really inefficient, and the other two helpers
are also needed to compile some modules.

Add the missing versions, and export all of the symbols like arm64
already does.

This code is based on the assembly generated by libgcc builds.

This fixes a build break triggered by ubsan:

riscv64-unknown-linux-gnu-ld: lib/ubsan.o: in function `.L2':
ubsan.c:(.text.unlikely+0x38): undefined reference to `__ashlti3'
riscv64-unknown-linux-gnu-ld: ubsan.c:(.text.unlikely+0x42): undefined reference to `__ashrti3'

Signed-off-by: Olof Johansson &lt;olof@lixom.net&gt;
[paul.walmsley@sifive.com: use SYM_FUNC_{START,END} instead of
 ENTRY/ENDPROC; note libgcc origin]
Signed-off-by: Paul Walmsley &lt;paul.walmsley@sifive.com&gt;
Signed-off-by: Sudip Mukherjee &lt;sudipm.mukherjee@gmail.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit fc585d4a5cf614727f64d86550b794bcad29d5c3 upstream.

The existing __lshrti3 was really inefficient, and the other two helpers
are also needed to compile some modules.

Add the missing versions, and export all of the symbols like arm64
already does.

This code is based on the assembly generated by libgcc builds.

This fixes a build break triggered by ubsan:

riscv64-unknown-linux-gnu-ld: lib/ubsan.o: in function `.L2':
ubsan.c:(.text.unlikely+0x38): undefined reference to `__ashlti3'
riscv64-unknown-linux-gnu-ld: ubsan.c:(.text.unlikely+0x42): undefined reference to `__ashrti3'

Signed-off-by: Olof Johansson &lt;olof@lixom.net&gt;
[paul.walmsley@sifive.com: use SYM_FUNC_{START,END} instead of
 ENTRY/ENDPROC; note libgcc origin]
Signed-off-by: Paul Walmsley &lt;paul.walmsley@sifive.com&gt;
Signed-off-by: Sudip Mukherjee &lt;sudipm.mukherjee@gmail.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>RISC-V: fix barrier() use in &lt;vdso/processor.h&gt;</title>
<updated>2022-06-22T12:11:24+00:00</updated>
<author>
<name>Randy Dunlap</name>
<email>rdunlap@infradead.org</email>
</author>
<published>2020-11-17T01:39:51+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=2464a1c0de5390d668b2a286b4a6ba2365d8bd2d'/>
<id>2464a1c0de5390d668b2a286b4a6ba2365d8bd2d</id>
<content type='text'>
commit 30aca1bacb398dec6c1ed5eeca33f355bd7b6203 upstream.

riscv's &lt;vdso/processor.h&gt; uses barrier() so it should include
&lt;asm/barrier.h&gt;

Fixes this build error:
  CC [M]  drivers/net/ethernet/emulex/benet/be_main.o
In file included from ./include/vdso/processor.h:10,
                 from ./arch/riscv/include/asm/processor.h:11,
                 from ./include/linux/prefetch.h:15,
                 from drivers/net/ethernet/emulex/benet/be_main.c:14:
./arch/riscv/include/asm/vdso/processor.h: In function 'cpu_relax':
./arch/riscv/include/asm/vdso/processor.h:14:2: error: implicit declaration of function 'barrier' [-Werror=implicit-function-declaration]
   14 |  barrier();

This happens with a total of 5 networking drivers -- they all use
&lt;linux/prefetch.h&gt;.

rv64 allmodconfig now builds cleanly after this patch.

Fixes fallout from:
815f0ddb346c ("include/linux/compiler*.h: make compiler-*.h mutually exclusive")

Fixes: ad5d1122b82f ("riscv: use vDSO common flow to reduce the latency of the time-related functions")
Reported-by: Andreas Schwab &lt;schwab@linux-m68k.org&gt;
Signed-off-by: Randy Dunlap &lt;rdunlap@infradead.org&gt;
Acked-by: Arvind Sankar &lt;nivedita@alum.mit.edu&gt;
Signed-off-by: Palmer Dabbelt &lt;palmerdabbelt@google.com&gt;
Reviewed-by: Nick Desaulniers &lt;ndesaulniers@google.com&gt;
Signed-off-by: Palmer Dabbelt &lt;palmerdabbelt@google.com&gt;
[sudip: change in old path]
Signed-off-by: Sudip Mukherjee &lt;sudipm.mukherjee@gmail.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 30aca1bacb398dec6c1ed5eeca33f355bd7b6203 upstream.

riscv's &lt;vdso/processor.h&gt; uses barrier() so it should include
&lt;asm/barrier.h&gt;

Fixes this build error:
  CC [M]  drivers/net/ethernet/emulex/benet/be_main.o
In file included from ./include/vdso/processor.h:10,
                 from ./arch/riscv/include/asm/processor.h:11,
                 from ./include/linux/prefetch.h:15,
                 from drivers/net/ethernet/emulex/benet/be_main.c:14:
./arch/riscv/include/asm/vdso/processor.h: In function 'cpu_relax':
./arch/riscv/include/asm/vdso/processor.h:14:2: error: implicit declaration of function 'barrier' [-Werror=implicit-function-declaration]
   14 |  barrier();

This happens with a total of 5 networking drivers -- they all use
&lt;linux/prefetch.h&gt;.

rv64 allmodconfig now builds cleanly after this patch.

Fixes fallout from:
815f0ddb346c ("include/linux/compiler*.h: make compiler-*.h mutually exclusive")

Fixes: ad5d1122b82f ("riscv: use vDSO common flow to reduce the latency of the time-related functions")
Reported-by: Andreas Schwab &lt;schwab@linux-m68k.org&gt;
Signed-off-by: Randy Dunlap &lt;rdunlap@infradead.org&gt;
Acked-by: Arvind Sankar &lt;nivedita@alum.mit.edu&gt;
Signed-off-by: Palmer Dabbelt &lt;palmerdabbelt@google.com&gt;
Reviewed-by: Nick Desaulniers &lt;ndesaulniers@google.com&gt;
Signed-off-by: Palmer Dabbelt &lt;palmerdabbelt@google.com&gt;
[sudip: change in old path]
Signed-off-by: Sudip Mukherjee &lt;sudipm.mukherjee@gmail.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>riscv: Workaround mcount name prior to clang-13</title>
<updated>2021-05-22T09:38:29+00:00</updated>
<author>
<name>Nathan Chancellor</name>
<email>nathan@kernel.org</email>
</author>
<published>2021-03-25T22:38:06+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=e69c7c1491997407a44aa1101d93675d803647ec'/>
<id>e69c7c1491997407a44aa1101d93675d803647ec</id>
<content type='text'>
[ Upstream commit 7ce04771503074a7de7f539cc43f5e1b385cb99b ]

Prior to clang 13.0.0, the RISC-V name for the mcount symbol was
"mcount", which differs from the GCC version of "_mcount", which results
in the following errors:

riscv64-linux-gnu-ld: init/main.o: in function `__traceiter_initcall_level':
main.c:(.text+0xe): undefined reference to `mcount'
riscv64-linux-gnu-ld: init/main.o: in function `__traceiter_initcall_start':
main.c:(.text+0x4e): undefined reference to `mcount'
riscv64-linux-gnu-ld: init/main.o: in function `__traceiter_initcall_finish':
main.c:(.text+0x92): undefined reference to `mcount'
riscv64-linux-gnu-ld: init/main.o: in function `.LBB32_28':
main.c:(.text+0x30c): undefined reference to `mcount'
riscv64-linux-gnu-ld: init/main.o: in function `free_initmem':
main.c:(.text+0x54c): undefined reference to `mcount'

This has been corrected in https://reviews.llvm.org/D98881 but the
minimum supported clang version is 10.0.1. To avoid build errors and to
gain a working function tracer, adjust the name of the mcount symbol for
older versions of clang in mount.S and recordmcount.pl.

Link: https://github.com/ClangBuiltLinux/linux/issues/1331
Signed-off-by: Nathan Chancellor &lt;nathan@kernel.org&gt;
Reviewed-by: Nick Desaulniers &lt;ndesaulniers@google.com&gt;
Signed-off-by: Palmer Dabbelt &lt;palmerdabbelt@google.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 7ce04771503074a7de7f539cc43f5e1b385cb99b ]

Prior to clang 13.0.0, the RISC-V name for the mcount symbol was
"mcount", which differs from the GCC version of "_mcount", which results
in the following errors:

riscv64-linux-gnu-ld: init/main.o: in function `__traceiter_initcall_level':
main.c:(.text+0xe): undefined reference to `mcount'
riscv64-linux-gnu-ld: init/main.o: in function `__traceiter_initcall_start':
main.c:(.text+0x4e): undefined reference to `mcount'
riscv64-linux-gnu-ld: init/main.o: in function `__traceiter_initcall_finish':
main.c:(.text+0x92): undefined reference to `mcount'
riscv64-linux-gnu-ld: init/main.o: in function `.LBB32_28':
main.c:(.text+0x30c): undefined reference to `mcount'
riscv64-linux-gnu-ld: init/main.o: in function `free_initmem':
main.c:(.text+0x54c): undefined reference to `mcount'

This has been corrected in https://reviews.llvm.org/D98881 but the
minimum supported clang version is 10.0.1. To avoid build errors and to
gain a working function tracer, adjust the name of the mcount symbol for
older versions of clang in mount.S and recordmcount.pl.

Link: https://github.com/ClangBuiltLinux/linux/issues/1331
Signed-off-by: Nathan Chancellor &lt;nathan@kernel.org&gt;
Reviewed-by: Nick Desaulniers &lt;ndesaulniers@google.com&gt;
Signed-off-by: Palmer Dabbelt &lt;palmerdabbelt@google.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>riscv: virt_addr_valid must check the address belongs to linear mapping</title>
<updated>2021-02-17T09:35:16+00:00</updated>
<author>
<name>Alexandre Ghiti</name>
<email>alex@ghiti.fr</email>
</author>
<published>2021-01-29T17:31:05+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=91d604ab2a9910c1c585abe5f491cc016a77e1ac'/>
<id>91d604ab2a9910c1c585abe5f491cc016a77e1ac</id>
<content type='text'>
[ Upstream commit 2ab543823322b564f205cb15d0f0302803c87d11 ]

virt_addr_valid macro checks that a virtual address is valid, ie that
the address belongs to the linear mapping and that the corresponding
 physical page exists.

Add the missing check that ensures the virtual address belongs to the
linear mapping, otherwise __virt_to_phys, when compiled with
CONFIG_DEBUG_VIRTUAL enabled, raises a WARN that is interpreted as a
kernel bug by syzbot.

Signed-off-by: Alexandre Ghiti &lt;alex@ghiti.fr&gt;
Reviewed-by: Atish Patra &lt;atish.patra@wdc.com&gt;
Signed-off-by: Palmer Dabbelt &lt;palmerdabbelt@google.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 2ab543823322b564f205cb15d0f0302803c87d11 ]

virt_addr_valid macro checks that a virtual address is valid, ie that
the address belongs to the linear mapping and that the corresponding
 physical page exists.

Add the missing check that ensures the virtual address belongs to the
linear mapping, otherwise __virt_to_phys, when compiled with
CONFIG_DEBUG_VIRTUAL enabled, raises a WARN that is interpreted as a
kernel bug by syzbot.

Signed-off-by: Alexandre Ghiti &lt;alex@ghiti.fr&gt;
Reviewed-by: Atish Patra &lt;atish.patra@wdc.com&gt;
Signed-off-by: Palmer Dabbelt &lt;palmerdabbelt@google.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>arch: pgtable: define MAX_POSSIBLE_PHYSMEM_BITS where needed</title>
<updated>2020-12-02T07:49:50+00:00</updated>
<author>
<name>Arnd Bergmann</name>
<email>arnd@arndb.de</email>
</author>
<published>2020-11-11T16:52:58+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=1bef5f25a69234613b92a0e2456870fee4a57efc'/>
<id>1bef5f25a69234613b92a0e2456870fee4a57efc</id>
<content type='text'>
[ Upstream commit cef397038167ac15d085914493d6c86385773709 ]

Stefan Agner reported a bug when using zsram on 32-bit Arm machines
with RAM above the 4GB address boundary:

  Unable to handle kernel NULL pointer dereference at virtual address 00000000
  pgd = a27bd01c
  [00000000] *pgd=236a0003, *pmd=1ffa64003
  Internal error: Oops: 207 [#1] SMP ARM
  Modules linked in: mdio_bcm_unimac(+) brcmfmac cfg80211 brcmutil raspberrypi_hwmon hci_uart crc32_arm_ce bcm2711_thermal phy_generic genet
  CPU: 0 PID: 123 Comm: mkfs.ext4 Not tainted 5.9.6 #1
  Hardware name: BCM2711
  PC is at zs_map_object+0x94/0x338
  LR is at zram_bvec_rw.constprop.0+0x330/0xa64
  pc : [&lt;c0602b38&gt;]    lr : [&lt;c0bda6a0&gt;]    psr: 60000013
  sp : e376bbe0  ip : 00000000  fp : c1e2921c
  r10: 00000002  r9 : c1dda730  r8 : 00000000
  r7 : e8ff7a00  r6 : 00000000  r5 : 02f9ffa0  r4 : e3710000
  r3 : 000fdffe  r2 : c1e0ce80  r1 : ebf979a0  r0 : 00000000
  Flags: nZCv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment user
  Control: 30c5383d  Table: 235c2a80  DAC: fffffffd
  Process mkfs.ext4 (pid: 123, stack limit = 0x495a22e6)
  Stack: (0xe376bbe0 to 0xe376c000)

As it turns out, zsram needs to know the maximum memory size, which
is defined in MAX_PHYSMEM_BITS when CONFIG_SPARSEMEM is set, or in
MAX_POSSIBLE_PHYSMEM_BITS on the x86 architecture.

The same problem will be hit on all 32-bit architectures that have a
physical address space larger than 4GB and happen to not enable sparsemem
and include asm/sparsemem.h from asm/pgtable.h.

After the initial discussion, I suggested just always defining
MAX_POSSIBLE_PHYSMEM_BITS whenever CONFIG_PHYS_ADDR_T_64BIT is
set, or provoking a build error otherwise. This addresses all
configurations that can currently have this runtime bug, but
leaves all other configurations unchanged.

I looked up the possible number of bits in source code and
datasheets, here is what I found:

 - on ARC, CONFIG_ARC_HAS_PAE40 controls whether 32 or 40 bits are used
 - on ARM, CONFIG_LPAE enables 40 bit addressing, without it we never
   support more than 32 bits, even though supersections in theory allow
   up to 40 bits as well.
 - on MIPS, some MIPS32r1 or later chips support 36 bits, and MIPS32r5
   XPA supports up to 60 bits in theory, but 40 bits are more than
   anyone will ever ship
 - On PowerPC, there are three different implementations of 36 bit
   addressing, but 32-bit is used without CONFIG_PTE_64BIT
 - On RISC-V, the normal page table format can support 34 bit
   addressing. There is no highmem support on RISC-V, so anything
   above 2GB is unused, but it might be useful to eventually support
   CONFIG_ZRAM for high pages.

Fixes: 61989a80fb3a ("staging: zsmalloc: zsmalloc memory allocation library")
Fixes: 02390b87a945 ("mm/zsmalloc: Prepare to variable MAX_PHYSMEM_BITS")
Acked-by: Thomas Bogendoerfer &lt;tsbogend@alpha.franken.de&gt;
Reviewed-by: Stefan Agner &lt;stefan@agner.ch&gt;
Tested-by: Stefan Agner &lt;stefan@agner.ch&gt;
Acked-by: Mike Rapoport &lt;rppt@linux.ibm.com&gt;
Link: https://lore.kernel.org/linux-mm/bdfa44bf1c570b05d6c70898e2bbb0acf234ecdf.1604762181.git.stefan@agner.ch/
Signed-off-by: Arnd Bergmann &lt;arnd@arndb.de&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit cef397038167ac15d085914493d6c86385773709 ]

Stefan Agner reported a bug when using zsram on 32-bit Arm machines
with RAM above the 4GB address boundary:

  Unable to handle kernel NULL pointer dereference at virtual address 00000000
  pgd = a27bd01c
  [00000000] *pgd=236a0003, *pmd=1ffa64003
  Internal error: Oops: 207 [#1] SMP ARM
  Modules linked in: mdio_bcm_unimac(+) brcmfmac cfg80211 brcmutil raspberrypi_hwmon hci_uart crc32_arm_ce bcm2711_thermal phy_generic genet
  CPU: 0 PID: 123 Comm: mkfs.ext4 Not tainted 5.9.6 #1
  Hardware name: BCM2711
  PC is at zs_map_object+0x94/0x338
  LR is at zram_bvec_rw.constprop.0+0x330/0xa64
  pc : [&lt;c0602b38&gt;]    lr : [&lt;c0bda6a0&gt;]    psr: 60000013
  sp : e376bbe0  ip : 00000000  fp : c1e2921c
  r10: 00000002  r9 : c1dda730  r8 : 00000000
  r7 : e8ff7a00  r6 : 00000000  r5 : 02f9ffa0  r4 : e3710000
  r3 : 000fdffe  r2 : c1e0ce80  r1 : ebf979a0  r0 : 00000000
  Flags: nZCv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment user
  Control: 30c5383d  Table: 235c2a80  DAC: fffffffd
  Process mkfs.ext4 (pid: 123, stack limit = 0x495a22e6)
  Stack: (0xe376bbe0 to 0xe376c000)

As it turns out, zsram needs to know the maximum memory size, which
is defined in MAX_PHYSMEM_BITS when CONFIG_SPARSEMEM is set, or in
MAX_POSSIBLE_PHYSMEM_BITS on the x86 architecture.

The same problem will be hit on all 32-bit architectures that have a
physical address space larger than 4GB and happen to not enable sparsemem
and include asm/sparsemem.h from asm/pgtable.h.

After the initial discussion, I suggested just always defining
MAX_POSSIBLE_PHYSMEM_BITS whenever CONFIG_PHYS_ADDR_T_64BIT is
set, or provoking a build error otherwise. This addresses all
configurations that can currently have this runtime bug, but
leaves all other configurations unchanged.

I looked up the possible number of bits in source code and
datasheets, here is what I found:

 - on ARC, CONFIG_ARC_HAS_PAE40 controls whether 32 or 40 bits are used
 - on ARM, CONFIG_LPAE enables 40 bit addressing, without it we never
   support more than 32 bits, even though supersections in theory allow
   up to 40 bits as well.
 - on MIPS, some MIPS32r1 or later chips support 36 bits, and MIPS32r5
   XPA supports up to 60 bits in theory, but 40 bits are more than
   anyone will ever ship
 - On PowerPC, there are three different implementations of 36 bit
   addressing, but 32-bit is used without CONFIG_PTE_64BIT
 - On RISC-V, the normal page table format can support 34 bit
   addressing. There is no highmem support on RISC-V, so anything
   above 2GB is unused, but it might be useful to eventually support
   CONFIG_ZRAM for high pages.

Fixes: 61989a80fb3a ("staging: zsmalloc: zsmalloc memory allocation library")
Fixes: 02390b87a945 ("mm/zsmalloc: Prepare to variable MAX_PHYSMEM_BITS")
Acked-by: Thomas Bogendoerfer &lt;tsbogend@alpha.franken.de&gt;
Reviewed-by: Stefan Agner &lt;stefan@agner.ch&gt;
Tested-by: Stefan Agner &lt;stefan@agner.ch&gt;
Acked-by: Mike Rapoport &lt;rppt@linux.ibm.com&gt;
Link: https://lore.kernel.org/linux-mm/bdfa44bf1c570b05d6c70898e2bbb0acf234ecdf.1604762181.git.stefan@agner.ch/
Signed-off-by: Arnd Bergmann &lt;arnd@arndb.de&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>RISC-V: Take text_mutex in ftrace_init_nop()</title>
<updated>2020-10-01T11:18:14+00:00</updated>
<author>
<name>Palmer Dabbelt</name>
<email>palmerdabbelt@google.com</email>
</author>
<published>2020-08-25T00:21:22+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=66d987b80dc34236777318000ca94c3b963f8aca'/>
<id>66d987b80dc34236777318000ca94c3b963f8aca</id>
<content type='text'>
[ Upstream commit 66d18dbda8469a944dfec6c49d26d5946efba218 ]

Without this we get lockdep failures.  They're spurious failures as SMP isn't
up when ftrace_init_nop() is called.  As far as I can tell the easiest fix is
to just take the lock, which also seems like the safest fix.

Signed-off-by: Palmer Dabbelt &lt;palmerdabbelt@google.com&gt;
Acked-by: Guo Ren &lt;guoren@kernel.org&gt;
Signed-off-by: Palmer Dabbelt &lt;palmerdabbelt@google.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 66d18dbda8469a944dfec6c49d26d5946efba218 ]

Without this we get lockdep failures.  They're spurious failures as SMP isn't
up when ftrace_init_nop() is called.  As far as I can tell the easiest fix is
to just take the lock, which also seems like the safest fix.

Signed-off-by: Palmer Dabbelt &lt;palmerdabbelt@google.com&gt;
Acked-by: Guo Ren &lt;guoren@kernel.org&gt;
Signed-off-by: Palmer Dabbelt &lt;palmerdabbelt@google.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>RISC-V: Upgrade smp_mb__after_spinlock() to iorw,iorw</title>
<updated>2020-07-29T08:18:40+00:00</updated>
<author>
<name>Palmer Dabbelt</name>
<email>palmerdabbelt@google.com</email>
</author>
<published>2020-07-16T18:57:26+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=35728cac176a1cc1c57aa87a1e55e95a0ee3e985'/>
<id>35728cac176a1cc1c57aa87a1e55e95a0ee3e985</id>
<content type='text'>
[ Upstream commit 38b7c2a3ffb1fce8358ddc6006cfe5c038ff9963 ]

While digging through the recent mmiowb preemption issue it came up that
we aren't actually preventing IO from crossing a scheduling boundary.
While it's a bit ugly to overload smp_mb__after_spinlock() with this
behavior, it's what PowerPC is doing so there's some precedent.

Signed-off-by: Palmer Dabbelt &lt;palmerdabbelt@google.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 38b7c2a3ffb1fce8358ddc6006cfe5c038ff9963 ]

While digging through the recent mmiowb preemption issue it came up that
we aren't actually preventing IO from crossing a scheduling boundary.
While it's a bit ugly to overload smp_mb__after_spinlock() with this
behavior, it's what PowerPC is doing so there's some precedent.

Signed-off-by: Palmer Dabbelt &lt;palmerdabbelt@google.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>riscv: use 16KB kernel stack on 64-bit</title>
<updated>2020-07-22T07:33:14+00:00</updated>
<author>
<name>Andreas Schwab</name>
<email>schwab@suse.de</email>
</author>
<published>2020-07-06T12:32:26+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=9125d5762590bb99d65b0f3f1c37c0585a576e67'/>
<id>9125d5762590bb99d65b0f3f1c37c0585a576e67</id>
<content type='text'>
commit 0cac21b02ba5f3095fd2dcc77c26a25a0b2432ed upstream.

With the current 8KB stack size there are frequent overflows in a 64-bit
configuration.  We may split IRQ stacks off in the future, but this fixes a
number of issues right now.

Signed-off-by: Andreas Schwab &lt;schwab@suse.de&gt;
Reviewed-by: Anup Patel &lt;anup@brainfault.org&gt;
[Palmer: mention irqstack in the commit text]
Fixes: 7db91e57a0ac ("RISC-V: Task implementation")
Cc: stable@vger.kernel.org
Signed-off-by: Palmer Dabbelt &lt;palmerdabbelt@google.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
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<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 0cac21b02ba5f3095fd2dcc77c26a25a0b2432ed upstream.

With the current 8KB stack size there are frequent overflows in a 64-bit
configuration.  We may split IRQ stacks off in the future, but this fixes a
number of issues right now.

Signed-off-by: Andreas Schwab &lt;schwab@suse.de&gt;
Reviewed-by: Anup Patel &lt;anup@brainfault.org&gt;
[Palmer: mention irqstack in the commit text]
Fixes: 7db91e57a0ac ("RISC-V: Task implementation")
Cc: stable@vger.kernel.org
Signed-off-by: Palmer Dabbelt &lt;palmerdabbelt@google.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
</feed>
