* RE: [PATCH 12/14] x86: remove address space overrides using set_fs()
From: David Laight @ 2020-09-04 7:59 UTC (permalink / raw)
To: 'Linus Torvalds'
Cc: linux-arch@vger.kernel.org, Kees Cook, x86@kernel.org,
linux-kernel@vger.kernel.org, Christoph Hellwig, Luis Chamberlain,
Al Viro, linux-fsdevel@vger.kernel.org,
linuxppc-dev@lists.ozlabs.org, Alexey Dobriyan
In-Reply-To: <CAHk-=whDtnudkbZ8-hR8HiDE7zog0dv+Gu9Sx5i6SPakrDtajQ@mail.gmail.com>
From: Linus Torvalds
> Sent: 04 September 2020 00:26
>
> On Thu, Sep 3, 2020 at 2:30 PM David Laight <David.Laight@aculab.com> wrote:
> >
> > A non-canonical (is that the right term) address between the highest
> > valid user address and the lowest valid kernel address (7ffe to fffe?)
> > will fault anyway.
>
> Yes.
>
> But we actually warn against that fault, because it's been a good way
> to catch places that didn't use the proper "access_ok()" pattern.
>
> See ex_handler_uaccess() and the
>
> WARN_ONCE(trapnr == X86_TRAP_GP, "General protection fault in
> user access. Non-canonical address?");
>
> warning. It's been good for randomized testing - a missing range check
> on a user address will often hit this.
>
> Of course, you should never see it in real life (and hopefully not in
> testing either any more). But belt-and-suspenders..
That could still be effective, just pick an address limit that is
appropriate for the one access_ok() is using.
Even if access_ok() uses 1<<63 there are plenty of addresses above it that fault.
But the upper limit for 5-level page tables could be used all the time.
One option is to test '(address | length) < (3<<62)' in access_ok().
That is also moderately suitable for masking invalid addresses to 0.
David
-
Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK
Registration No: 1397386 (Wales)
^ permalink raw reply
* Re: ptrace_syscall_32 is failing
From: Thomas Gleixner @ 2020-09-04 10:13 UTC (permalink / raw)
To: Andy Lutomirski
Cc: linux-s390, linuxppc-dev, Vasily Gorbik, Brian Gerst,
Heiko Carstens, X86 ML, LKML, Christian Borntraeger,
Paul Mackerras, Catalin Marinas, Andy Lutomirski, Will Deacon,
linux-arm-kernel
In-Reply-To: <CALCETrUuyXpG0Vhrb-9m-G8J94+2bGqdrJkKfz+-5z7dsGLK8Q@mail.gmail.com>
Andy,
On Wed, Sep 02 2020 at 09:49, Andy Lutomirski wrote:
> On Wed, Sep 2, 2020 at 1:29 AM Thomas Gleixner <tglx@linutronix.de> wrote:
>>
>> But you might tell me where exactly you want to inject the SIGTRAP in
>> the syscall exit code flow.
>
> It would be a bit complicated. Definitely after any signals from the
> syscall are delivered. Right now, I think that we don't deliver a
> SIGTRAP on the instruction boundary after SYSCALL while
> single-stepping. (I think we used to, but only sometimes, and now we
> are at least consistent.) This is because IRET will not trap if it
> starts with TF clear and ends up setting it. (I asked Intel to
> document this, and I think they finally did, although I haven't gotten
> around to reading the new docs. Certainly the old docs as of a year
> or two ago had no description whatsoever of how TF changes worked.)
>
> Deciding exactly *when* a trap should occur would be nontrivial -- we
> can't trap on sigreturn() from a SIGTRAP, for example.
>
> So this isn't fully worked out.
Oh well.
>> >> I don't think we want that in general. The current variant is perfectly
>> >> fine for everything except the 32bit fast syscall nonsense. Also
>> >> irqentry_entry/exit is not equivalent to the syscall_enter/exit
>> >> counterparts.
>> >
>> > If there are any architectures in which actual work is needed to
>> > figure out whether something is a syscall in the first place, they'll
>> > want to do the usual kernel entry work before the syscall entry work.
>>
>> That's low level entry code which does not require RCU, lockdep, tracing
>> or whatever muck we setup before actual work can be done.
>>
>> arch_asm_entry()
>> ...
>> arch_c_entry(cause) {
>> switch(cause) {
>> case EXCEPTION: arch_c_exception(...);
>> case SYSCALL: arch_c_syscall(...);
>> ...
>> }
>
> You're assuming that figuring out the cause doesn't need the kernel
> entry code to run first. In the case of the 32-bit vDSO fast
> syscalls, we arguably don't know whether an entry is a syscall until
> we have done a user memory access. Logically, we're doing:
>
> if (get_user() < 0) {
> /* Not a syscall. This is actually a silly operation that sets AX =
> -EFAULT and returns. Do not audit or invoke ptrace. */
> } else {
> /* This actually is a syscall. */
> }
Yes, that's what I've addressed with providing split interfaces.
>> You really want to differentiate between exception and syscall
>> entry/exit.
>>
>
> Why do we want to distinguish between exception and syscall
> entry/exit? For the enter part, AFAICS the exception case boils down
> to enter_from_user_mode() and the syscall case is:
>
> enter_from_user_mode(regs);
> instrumentation_begin();
>
> local_irq_enable();
> ti_work = READ_ONCE(current_thread_info()->flags);
> if (ti_work & SYSCALL_ENTER_WORK)
> syscall = syscall_trace_enter(regs, syscall, ti_work);
> instrumentation_end();
>
> Which would decompose quite nicely as a regular (non-syscall) entry
> plus the syscall part later.
There is a difference between syscall entry and exception entry at least
in my view:
syscall:
enter_from_user_mode(regs);
local_irq_enable();
exception:
enter_from_user_mode(regs);
>> we'd have:
>>
>> arch_c_entry()
>> irqentry_enter();
>> local_irq_enble();
>> nr = syscall_enter_from_user_mode_work();
>> ...
>>
>> which enforces two calls for sane entries and more code in arch/....
>
> This is why I still like my:
>
> arch_c_entry()
> irqentry_enter_from_user_mode();
> generic_syscall();
> exit...
So what we have now (with my patch applied) is either:
1) arch_c_entry()
nr = syscall_enter_from_user_mode();
arch_handle_syscall(nr);
syscall_exit_to_user_mode();
or for that extra 32bit fast syscall thing:
2) arch_c_entry()
syscall_enter_from_user_mode_prepare();
arch_do_stuff();
nr = syscall_enter_from_user_mode_work();
arch_handle_syscall(nr);
syscall_exit_to_user_mode();
So for sane cases you just use #1.
Ideally we'd not need arch_handle_syscall(nr) at all, but that does not
work with multiple ABIs supported, i.e. the compat muck.
The only way we could make that work is to have:
syscall_enter_exit(regs, mode)
nr = syscall_enter_from_user_mode();
arch_handle_syscall(mode, nr);
syscall_exit_to_user_mode();
and then arch_c_entry() becomes:
syscall_enter_exit(regs, mode);
which means that arch_handle_syscall() would have to evaluate the mode
and chose the appropriate syscall table. Not sure whether that's a win.
Thanks,
tglx
^ permalink raw reply
* [PATCH] powerpc/uaccess: Add pre-update addressing to __put_user_asm_goto()
From: Christophe Leroy @ 2020-09-04 10:46 UTC (permalink / raw)
To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman
Cc: linuxppc-dev, linux-kernel
Enable pre-update addressing mode in __put_user_asm_goto()
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
arch/powerpc/include/asm/uaccess.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/powerpc/include/asm/uaccess.h b/arch/powerpc/include/asm/uaccess.h
index 7c2427f237e1..a5cfe867fbdc 100644
--- a/arch/powerpc/include/asm/uaccess.h
+++ b/arch/powerpc/include/asm/uaccess.h
@@ -254,7 +254,7 @@ do { \
"1: " op "%U1%X1 %0,%1 # put_user\n" \
EX_TABLE(1b, %l2) \
: \
- : "r" (x), "m" (*addr) \
+ : "r" (x), "m<>" (*addr) \
: \
: label)
--
2.25.0
^ permalink raw reply related
* [PATCH 1/3] powerpc/uaccess: Switch __put_user_size_allowed() to __put_user_asm_goto()
From: Christophe Leroy @ 2020-09-04 11:01 UTC (permalink / raw)
To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman
Cc: linuxppc-dev, linux-kernel
__put_user_asm_goto() provides more flexibility to GCC and avoids using
a local variable to tell if the write succeeded or not.
GCC can then avoid implementing a cmp in the fast path.
See the difference for a small function like the PPC64 version of
save_general_regs() in arch/powerpc/kernel/signal_32.c:
Before the patch (unreachable nop removed):
0000000000000c10 <.save_general_regs>:
c10: 39 20 00 2c li r9,44
c14: 39 40 00 00 li r10,0
c18: 7d 29 03 a6 mtctr r9
c1c: 38 c0 00 00 li r6,0
c20: 48 00 00 14 b c34 <.save_general_regs+0x24>
c30: 42 40 00 40 bdz c70 <.save_general_regs+0x60>
c34: 28 2a 00 27 cmpldi r10,39
c38: 7c c8 33 78 mr r8,r6
c3c: 79 47 1f 24 rldicr r7,r10,3,60
c40: 39 20 00 01 li r9,1
c44: 41 82 00 0c beq c50 <.save_general_regs+0x40>
c48: 7d 23 38 2a ldx r9,r3,r7
c4c: 79 29 00 20 clrldi r9,r9,32
c50: 91 24 00 00 stw r9,0(r4)
c54: 2c 28 00 00 cmpdi r8,0
c58: 39 4a 00 01 addi r10,r10,1
c5c: 38 84 00 04 addi r4,r4,4
c60: 41 82 ff d0 beq c30 <.save_general_regs+0x20>
c64: 38 60 ff f2 li r3,-14
c68: 4e 80 00 20 blr
c70: 38 60 00 00 li r3,0
c74: 4e 80 00 20 blr
0000000000000000 <.fixup>:
cc: 39 00 ff f2 li r8,-14
d0: 48 00 00 00 b d0 <.fixup+0xd0>
d0: R_PPC64_REL24 .text+0xc54
After the patch:
0000000000001490 <.save_general_regs>:
1490: 39 20 00 2c li r9,44
1494: 39 40 00 00 li r10,0
1498: 7d 29 03 a6 mtctr r9
149c: 60 00 00 00 nop
14a0: 28 2a 00 27 cmpldi r10,39
14a4: 79 48 1f 24 rldicr r8,r10,3,60
14a8: 39 20 00 01 li r9,1
14ac: 41 82 00 0c beq 14b8 <.save_general_regs+0x28>
14b0: 7d 23 40 2a ldx r9,r3,r8
14b4: 79 29 00 20 clrldi r9,r9,32
14b8: 91 24 00 00 stw r9,0(r4)
14bc: 39 4a 00 01 addi r10,r10,1
14c0: 38 84 00 04 addi r4,r4,4
14c4: 42 00 ff dc bdnz 14a0 <.save_general_regs+0x10>
14c8: 38 60 00 00 li r3,0
14cc: 4e 80 00 20 blr
14d0: 38 60 ff f2 li r3,-14
14d4: 4e 80 00 20 blr
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
arch/powerpc/include/asm/uaccess.h | 14 +++++++-------
1 file changed, 7 insertions(+), 7 deletions(-)
diff --git a/arch/powerpc/include/asm/uaccess.h b/arch/powerpc/include/asm/uaccess.h
index a5cfe867fbdc..96d1c144f92b 100644
--- a/arch/powerpc/include/asm/uaccess.h
+++ b/arch/powerpc/include/asm/uaccess.h
@@ -189,14 +189,14 @@ extern long __put_user_bad(void);
#define __put_user_size_allowed(x, ptr, size, retval) \
do { \
+ __label__ __pu_failed; \
+ \
retval = 0; \
- switch (size) { \
- case 1: __put_user_asm(x, ptr, retval, "stb"); break; \
- case 2: __put_user_asm(x, ptr, retval, "sth"); break; \
- case 4: __put_user_asm(x, ptr, retval, "stw"); break; \
- case 8: __put_user_asm2(x, ptr, retval); break; \
- default: __put_user_bad(); \
- } \
+ __put_user_size_goto(x, ptr, size, __pu_failed); \
+ break; \
+ \
+__pu_failed: \
+ retval = -EFAULT; \
} while (0)
#define __put_user_size(x, ptr, size, retval) \
--
2.25.0
^ permalink raw reply related
* [PATCH 2/3] powerpc/uaccess: Switch __patch_instruction() to __put_user_asm_goto()
From: Christophe Leroy @ 2020-09-04 11:01 UTC (permalink / raw)
To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman
Cc: linuxppc-dev, linux-kernel
In-Reply-To: <94ba5a5138f99522e1562dbcdb38d31aa790dc89.1599216721.git.christophe.leroy@csgroup.eu>
__patch_instruction() is the only user of __put_user_asm() outside
of asm/uaccess.h
Switch to the new __put_user_asm_goto() to enable retirement of
__put_user_asm() in a later patch.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
arch/powerpc/lib/code-patching.c | 17 +++++++----------
1 file changed, 7 insertions(+), 10 deletions(-)
diff --git a/arch/powerpc/lib/code-patching.c b/arch/powerpc/lib/code-patching.c
index 8c3934ea6220..2333625b5e31 100644
--- a/arch/powerpc/lib/code-patching.c
+++ b/arch/powerpc/lib/code-patching.c
@@ -21,21 +21,18 @@
static int __patch_instruction(struct ppc_inst *exec_addr, struct ppc_inst instr,
struct ppc_inst *patch_addr)
{
- int err = 0;
-
- if (!ppc_inst_prefixed(instr)) {
- __put_user_asm(ppc_inst_val(instr), patch_addr, err, "stw");
- } else {
- __put_user_asm(ppc_inst_as_u64(instr), patch_addr, err, "std");
- }
-
- if (err)
- return err;
+ if (!ppc_inst_prefixed(instr))
+ __put_user_asm_goto(ppc_inst_val(instr), patch_addr, failed, "stw");
+ else
+ __put_user_asm_goto(ppc_inst_as_u64(instr), patch_addr, failed, "std");
asm ("dcbst 0, %0; sync; icbi 0,%1; sync; isync" :: "r" (patch_addr),
"r" (exec_addr));
return 0;
+
+failed:
+ return -EFAULT;
}
int raw_patch_instruction(struct ppc_inst *addr, struct ppc_inst instr)
--
2.25.0
^ permalink raw reply related
* [PATCH 3/3] powerpc/uaccess: Remove __put_user_asm() and __put_user_asm2()
From: Christophe Leroy @ 2020-09-04 11:01 UTC (permalink / raw)
To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman
Cc: linuxppc-dev, linux-kernel
In-Reply-To: <94ba5a5138f99522e1562dbcdb38d31aa790dc89.1599216721.git.christophe.leroy@csgroup.eu>
__put_user_asm() and __put_user_asm2() are not used anymore.
Remove them.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
arch/powerpc/include/asm/uaccess.h | 41 ++++--------------------------
1 file changed, 5 insertions(+), 36 deletions(-)
diff --git a/arch/powerpc/include/asm/uaccess.h b/arch/powerpc/include/asm/uaccess.h
index 96d1c144f92b..26781b044932 100644
--- a/arch/powerpc/include/asm/uaccess.h
+++ b/arch/powerpc/include/asm/uaccess.h
@@ -151,42 +151,6 @@ static inline int __access_ok(unsigned long addr, unsigned long size,
extern long __put_user_bad(void);
-/*
- * We don't tell gcc that we are accessing memory, but this is OK
- * because we do not write to any memory gcc knows about, so there
- * are no aliasing issues.
- */
-#define __put_user_asm(x, addr, err, op) \
- __asm__ __volatile__( \
- "1: " op "%U2%X2 %1,%2 # put_user\n" \
- "2:\n" \
- ".section .fixup,\"ax\"\n" \
- "3: li %0,%3\n" \
- " b 2b\n" \
- ".previous\n" \
- EX_TABLE(1b, 3b) \
- : "=r" (err) \
- : "r" (x), "m<>" (*addr), "i" (-EFAULT), "0" (err))
-
-#ifdef __powerpc64__
-#define __put_user_asm2(x, ptr, retval) \
- __put_user_asm(x, ptr, retval, "std")
-#else /* __powerpc64__ */
-#define __put_user_asm2(x, addr, err) \
- __asm__ __volatile__( \
- "1: stw%X2 %1,%2\n" \
- "2: stw%X2 %L1,%L2\n" \
- "3:\n" \
- ".section .fixup,\"ax\"\n" \
- "4: li %0,%3\n" \
- " b 3b\n" \
- ".previous\n" \
- EX_TABLE(1b, 4b) \
- EX_TABLE(2b, 4b) \
- : "=r" (err) \
- : "r" (x), "m" (*addr), "i" (-EFAULT), "0" (err))
-#endif /* __powerpc64__ */
-
#define __put_user_size_allowed(x, ptr, size, retval) \
do { \
__label__ __pu_failed; \
@@ -249,6 +213,11 @@ do { \
})
+/*
+ * We don't tell gcc that we are accessing memory, but this is OK
+ * because we do not write to any memory gcc knows about, so there
+ * are no aliasing issues.
+ */
#define __put_user_asm_goto(x, addr, label, op) \
asm volatile goto( \
"1: " op "%U1%X1 %0,%1 # put_user\n" \
--
2.25.0
^ permalink raw reply related
* [PATCH] kbuild: preprocess module linker script
From: Masahiro Yamada @ 2020-09-04 13:31 UTC (permalink / raw)
To: linux-kbuild
Cc: linux-ia64, Peter Zijlstra, Catalin Marinas, Paul Mackerras,
linux-riscv, Will Deacon, Ard Biesheuvel, Anton Ivanov,
linux-arch, Mauro Carvalho Chehab, Richard Weinberger,
Masahiro Yamada, Russell King, Ingo Molnar, Geert Uytterhoeven,
Fenghua Yu, Albert Ou, Kees Cook, Arnd Bergmann, Jeff Dike,
Jessica Yu, linux-um, linux-m68k, Tony Luck, Paul Walmsley,
linux-arm-kernel, Michal Marek, linux-kernel, Palmer Dabbelt,
linuxppc-dev
There was a request to preprocess the module linker script like we do
for the vmlinux one (https://lkml.org/lkml/2020/8/21/512).
The difference between vmlinux.lds and module.lds is that the latter
is needed for external module builds, thus must be cleaned up by
'make mrproper' instead of 'make clean' (also, it must be created by
'make modules_prepare').
You cannot put it in arch/*/kernel/ because 'make clean' descends into
it. I moved arch/*/kernel/module.lds to arch/*/include/asm/module.lds.h,
which is included from scripts/module.lds.S.
scripts/module.lds is fine because 'make clean' keeps all the build
artifacts under scripts/.
You can add arch-specific sections in <asm/module.lds.h>.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Tested-by: Jessica Yu <jeyu@kernel.org>
---
Makefile | 1 -
arch/arm/Makefile | 4 ----
.../{kernel/module.lds => include/asm/module.lds.h} | 2 ++
arch/arm64/Makefile | 4 ----
.../{kernel/module.lds => include/asm/module.lds.h} | 2 ++
arch/ia64/Makefile | 1 -
arch/ia64/{module.lds => include/asm/module.lds.h} | 0
arch/m68k/Makefile | 1 -
.../{kernel/module.lds => include/asm/module.lds.h} | 0
arch/powerpc/Makefile | 1 -
.../{kernel/module.lds => include/asm/module.lds.h} | 0
arch/riscv/Makefile | 3 ---
.../{kernel/module.lds => include/asm/module.lds.h} | 3 ++-
arch/um/include/asm/Kbuild | 1 +
include/asm-generic/Kbuild | 1 +
include/asm-generic/module.lds.h | 10 ++++++++++
scripts/.gitignore | 1 +
scripts/Makefile | 2 ++
scripts/Makefile.modfinal | 5 ++---
scripts/{module-common.lds => module.lds.S} | 3 +++
scripts/package/builddeb | 2 +-
21 files changed, 27 insertions(+), 20 deletions(-)
rename arch/arm/{kernel/module.lds => include/asm/module.lds.h} (72%)
rename arch/arm64/{kernel/module.lds => include/asm/module.lds.h} (76%)
rename arch/ia64/{module.lds => include/asm/module.lds.h} (100%)
rename arch/m68k/{kernel/module.lds => include/asm/module.lds.h} (100%)
rename arch/powerpc/{kernel/module.lds => include/asm/module.lds.h} (100%)
rename arch/riscv/{kernel/module.lds => include/asm/module.lds.h} (84%)
create mode 100644 include/asm-generic/module.lds.h
rename scripts/{module-common.lds => module.lds.S} (93%)
diff --git a/Makefile b/Makefile
index 9cac6fde3479..3d9b56c6b47e 100644
--- a/Makefile
+++ b/Makefile
@@ -506,7 +506,6 @@ KBUILD_CFLAGS_KERNEL :=
KBUILD_AFLAGS_MODULE := -DMODULE
KBUILD_CFLAGS_MODULE := -DMODULE
KBUILD_LDFLAGS_MODULE :=
-export KBUILD_LDS_MODULE := $(srctree)/scripts/module-common.lds
KBUILD_LDFLAGS :=
CLANG_FLAGS :=
diff --git a/arch/arm/Makefile b/arch/arm/Makefile
index 4e877354515f..a0cb15de9677 100644
--- a/arch/arm/Makefile
+++ b/arch/arm/Makefile
@@ -16,10 +16,6 @@ LDFLAGS_vmlinux += --be8
KBUILD_LDFLAGS_MODULE += --be8
endif
-ifeq ($(CONFIG_ARM_MODULE_PLTS),y)
-KBUILD_LDS_MODULE += $(srctree)/arch/arm/kernel/module.lds
-endif
-
GZFLAGS :=-9
#KBUILD_CFLAGS +=-pipe
diff --git a/arch/arm/kernel/module.lds b/arch/arm/include/asm/module.lds.h
similarity index 72%
rename from arch/arm/kernel/module.lds
rename to arch/arm/include/asm/module.lds.h
index 79cb6af565e5..0e7cb4e314b4 100644
--- a/arch/arm/kernel/module.lds
+++ b/arch/arm/include/asm/module.lds.h
@@ -1,5 +1,7 @@
/* SPDX-License-Identifier: GPL-2.0 */
+#ifdef CONFIG_ARM_MODULE_PLTS
SECTIONS {
.plt : { BYTE(0) }
.init.plt : { BYTE(0) }
}
+#endif
diff --git a/arch/arm64/Makefile b/arch/arm64/Makefile
index 55bc8546d9c7..232547ec07d8 100644
--- a/arch/arm64/Makefile
+++ b/arch/arm64/Makefile
@@ -115,10 +115,6 @@ endif
CHECKFLAGS += -D__aarch64__
-ifeq ($(CONFIG_ARM64_MODULE_PLTS),y)
-KBUILD_LDS_MODULE += $(srctree)/arch/arm64/kernel/module.lds
-endif
-
ifeq ($(CONFIG_DYNAMIC_FTRACE_WITH_REGS),y)
KBUILD_CPPFLAGS += -DCC_USING_PATCHABLE_FUNCTION_ENTRY
CC_FLAGS_FTRACE := -fpatchable-function-entry=2
diff --git a/arch/arm64/kernel/module.lds b/arch/arm64/include/asm/module.lds.h
similarity index 76%
rename from arch/arm64/kernel/module.lds
rename to arch/arm64/include/asm/module.lds.h
index 22e36a21c113..691f15af788e 100644
--- a/arch/arm64/kernel/module.lds
+++ b/arch/arm64/include/asm/module.lds.h
@@ -1,5 +1,7 @@
+#ifdef CONFIG_ARM64_MODULE_PLTS
SECTIONS {
.plt (NOLOAD) : { BYTE(0) }
.init.plt (NOLOAD) : { BYTE(0) }
.text.ftrace_trampoline (NOLOAD) : { BYTE(0) }
}
+#endif
diff --git a/arch/ia64/Makefile b/arch/ia64/Makefile
index 2876a7df1b0a..703b1c4f6d12 100644
--- a/arch/ia64/Makefile
+++ b/arch/ia64/Makefile
@@ -20,7 +20,6 @@ CHECKFLAGS += -D__ia64=1 -D__ia64__=1 -D_LP64 -D__LP64__
OBJCOPYFLAGS := --strip-all
LDFLAGS_vmlinux := -static
-KBUILD_LDS_MODULE += $(srctree)/arch/ia64/module.lds
KBUILD_AFLAGS_KERNEL := -mconstant-gp
EXTRA :=
diff --git a/arch/ia64/module.lds b/arch/ia64/include/asm/module.lds.h
similarity index 100%
rename from arch/ia64/module.lds
rename to arch/ia64/include/asm/module.lds.h
diff --git a/arch/m68k/Makefile b/arch/m68k/Makefile
index 4438ffb4bbe1..ea14f2046fb4 100644
--- a/arch/m68k/Makefile
+++ b/arch/m68k/Makefile
@@ -75,7 +75,6 @@ KBUILD_CPPFLAGS += -D__uClinux__
endif
KBUILD_LDFLAGS := -m m68kelf
-KBUILD_LDS_MODULE += $(srctree)/arch/m68k/kernel/module.lds
ifdef CONFIG_SUN3
LDFLAGS_vmlinux = -N
diff --git a/arch/m68k/kernel/module.lds b/arch/m68k/include/asm/module.lds.h
similarity index 100%
rename from arch/m68k/kernel/module.lds
rename to arch/m68k/include/asm/module.lds.h
diff --git a/arch/powerpc/Makefile b/arch/powerpc/Makefile
index 3e8da9cf2eb9..8935658fcd06 100644
--- a/arch/powerpc/Makefile
+++ b/arch/powerpc/Makefile
@@ -65,7 +65,6 @@ UTS_MACHINE := $(subst $(space),,$(machine-y))
ifdef CONFIG_PPC32
KBUILD_LDFLAGS_MODULE += arch/powerpc/lib/crtsavres.o
else
-KBUILD_LDS_MODULE += $(srctree)/arch/powerpc/kernel/module.lds
ifeq ($(call ld-ifversion, -ge, 225000000, y),y)
# Have the linker provide sfpr if possible.
# There is a corresponding test in arch/powerpc/lib/Makefile
diff --git a/arch/powerpc/kernel/module.lds b/arch/powerpc/include/asm/module.lds.h
similarity index 100%
rename from arch/powerpc/kernel/module.lds
rename to arch/powerpc/include/asm/module.lds.h
diff --git a/arch/riscv/Makefile b/arch/riscv/Makefile
index fb6e37db836d..8edaa8bd86d6 100644
--- a/arch/riscv/Makefile
+++ b/arch/riscv/Makefile
@@ -53,9 +53,6 @@ endif
ifeq ($(CONFIG_CMODEL_MEDANY),y)
KBUILD_CFLAGS += -mcmodel=medany
endif
-ifeq ($(CONFIG_MODULE_SECTIONS),y)
- KBUILD_LDS_MODULE += $(srctree)/arch/riscv/kernel/module.lds
-endif
ifeq ($(CONFIG_PERF_EVENTS),y)
KBUILD_CFLAGS += -fno-omit-frame-pointer
endif
diff --git a/arch/riscv/kernel/module.lds b/arch/riscv/include/asm/module.lds.h
similarity index 84%
rename from arch/riscv/kernel/module.lds
rename to arch/riscv/include/asm/module.lds.h
index 295ecfb341a2..4254ff2ff049 100644
--- a/arch/riscv/kernel/module.lds
+++ b/arch/riscv/include/asm/module.lds.h
@@ -1,8 +1,9 @@
/* SPDX-License-Identifier: GPL-2.0 */
/* Copyright (C) 2017 Andes Technology Corporation */
-
+#ifdef CONFIG_MODULE_SECTIONS
SECTIONS {
.plt (NOLOAD) : { BYTE(0) }
.got (NOLOAD) : { BYTE(0) }
.got.plt (NOLOAD) : { BYTE(0) }
}
+#endif
diff --git a/arch/um/include/asm/Kbuild b/arch/um/include/asm/Kbuild
index 8d435f8a6dec..1c63b260ecc4 100644
--- a/arch/um/include/asm/Kbuild
+++ b/arch/um/include/asm/Kbuild
@@ -16,6 +16,7 @@ generic-y += kdebug.h
generic-y += mcs_spinlock.h
generic-y += mm-arch-hooks.h
generic-y += mmiowb.h
+generic-y += module.lds.h
generic-y += param.h
generic-y += pci.h
generic-y += percpu.h
diff --git a/include/asm-generic/Kbuild b/include/asm-generic/Kbuild
index 74b0612601dd..7cd4e627e00e 100644
--- a/include/asm-generic/Kbuild
+++ b/include/asm-generic/Kbuild
@@ -40,6 +40,7 @@ mandatory-y += mmiowb.h
mandatory-y += mmu.h
mandatory-y += mmu_context.h
mandatory-y += module.h
+mandatory-y += module.lds.h
mandatory-y += msi.h
mandatory-y += pci.h
mandatory-y += percpu.h
diff --git a/include/asm-generic/module.lds.h b/include/asm-generic/module.lds.h
new file mode 100644
index 000000000000..f210d5c1b78b
--- /dev/null
+++ b/include/asm-generic/module.lds.h
@@ -0,0 +1,10 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+#ifndef __ASM_GENERIC_MODULE_LDS_H
+#define __ASM_GENERIC_MODULE_LDS_H
+
+/*
+ * <asm/module.lds.h> can specify arch-specific sections for linking modules.
+ * Empty for the asm-generic header.
+ */
+
+#endif /* __ASM_GENERIC_MODULE_LDS_H */
diff --git a/scripts/.gitignore b/scripts/.gitignore
index 0d1c8e217cd7..a6c11316c969 100644
--- a/scripts/.gitignore
+++ b/scripts/.gitignore
@@ -8,3 +8,4 @@ asn1_compiler
extract-cert
sign-file
insert-sys-cert
+/module.lds
diff --git a/scripts/Makefile b/scripts/Makefile
index bc018e4b733e..a5058bfdd0f6 100644
--- a/scripts/Makefile
+++ b/scripts/Makefile
@@ -29,6 +29,8 @@ endif
# The following programs are only built on demand
hostprogs += unifdef
+always-$(CONFIG_MODULES) += module.lds
+
subdir-$(CONFIG_GCC_PLUGINS) += gcc-plugins
subdir-$(CONFIG_MODVERSIONS) += genksyms
subdir-$(CONFIG_SECURITY_SELINUX) += selinux
diff --git a/scripts/Makefile.modfinal b/scripts/Makefile.modfinal
index 411c1e600e7d..ae01baf96f4e 100644
--- a/scripts/Makefile.modfinal
+++ b/scripts/Makefile.modfinal
@@ -33,11 +33,10 @@ quiet_cmd_ld_ko_o = LD [M] $@
cmd_ld_ko_o = \
$(LD) -r $(KBUILD_LDFLAGS) \
$(KBUILD_LDFLAGS_MODULE) $(LDFLAGS_MODULE) \
- $(addprefix -T , $(KBUILD_LDS_MODULE)) \
- -o $@ $(filter %.o, $^); \
+ -T scripts/module.lds -o $@ $(filter %.o, $^); \
$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) $@, true)
-$(modules): %.ko: %.o %.mod.o $(KBUILD_LDS_MODULE) FORCE
+$(modules): %.ko: %.o %.mod.o scripts/module.lds FORCE
+$(call if_changed,ld_ko_o)
targets += $(modules) $(modules:.ko=.mod.o)
diff --git a/scripts/module-common.lds b/scripts/module.lds.S
similarity index 93%
rename from scripts/module-common.lds
rename to scripts/module.lds.S
index d61b9e8678e8..69b9b71a6a47 100644
--- a/scripts/module-common.lds
+++ b/scripts/module.lds.S
@@ -24,3 +24,6 @@ SECTIONS {
__jump_table 0 : ALIGN(8) { KEEP(*(__jump_table)) }
}
+
+/* bring in arch-specific sections */
+#include <asm/module.lds.h>
diff --git a/scripts/package/builddeb b/scripts/package/builddeb
index 6df3c9f8b2da..44f212e37935 100755
--- a/scripts/package/builddeb
+++ b/scripts/package/builddeb
@@ -55,7 +55,7 @@ deploy_kernel_headers () {
cd $srctree
find . arch/$SRCARCH -maxdepth 1 -name Makefile\*
find include scripts -type f -o -type l
- find arch/$SRCARCH -name module.lds -o -name Kbuild.platforms -o -name Platform
+ find arch/$SRCARCH -name Kbuild.platforms -o -name Platform
find $(find arch/$SRCARCH -name include -o -name scripts -type d) -type f
) > debian/hdrsrcfiles
--
2.25.1
^ permalink raw reply related
* Re: remove the last set_fs() in common code, and remove it for x86 and powerpc v3
From: Alexey Dobriyan @ 2020-09-04 17:58 UTC (permalink / raw)
To: Ingo Molnar
Cc: linux-arch, linuxppc-dev, Kees Cook, x86, linux-kernel,
Luis Chamberlain, Al Viro, linux-fsdevel, Linus Torvalds,
Christoph Hellwig
In-Reply-To: <20200904060024.GA2779810@gmail.com>
On Fri, Sep 04, 2020 at 08:00:24AM +0200, Ingo Molnar wrote:
> * Christoph Hellwig <hch@lst.de> wrote:
> > this series removes the last set_fs() used to force a kernel address
> > space for the uaccess code in the kernel read/write/splice code, and then
> > stops implementing the address space overrides entirely for x86 and
> > powerpc.
>
> Cool! For the x86 bits:
>
> Acked-by: Ingo Molnar <mingo@kernel.org>
set_fs() is older than some kernel hackers!
$ cd linux-0.11/
$ find . -type f -name '*.h' | xargs grep -e set_fs -w -n -A3
./include/asm/segment.h:61:extern inline void set_fs(unsigned long val)
./include/asm/segment.h-62-{
./include/asm/segment.h-63- __asm__("mov %0,%%fs"::"a" ((unsigned short) val));
./include/asm/segment.h-64-}
^ permalink raw reply
* Re: remove the last set_fs() in common code, and remove it for x86 and powerpc v3
From: Linus Torvalds @ 2020-09-04 18:42 UTC (permalink / raw)
To: Alexey Dobriyan
Cc: linux-arch, Kees Cook, the arch/x86 maintainers,
Linux Kernel Mailing List, Christoph Hellwig, Luis Chamberlain,
Al Viro, linux-fsdevel, linuxppc-dev, Ingo Molnar
In-Reply-To: <20200904175823.GA500051@localhost.localdomain>
On Fri, Sep 4, 2020 at 10:58 AM Alexey Dobriyan <adobriyan@gmail.com> wrote:
>
> set_fs() is older than some kernel hackers!
>
> $ cd linux-0.11/
> $ find . -type f -name '*.h' | xargs grep -e set_fs -w -n -A3
Oh, it's older than that. It was there (as set_fs) in 0.10, and may
even predate that. But sadly, I don't have tar-balls for 0.02 and
0.03, so can't check.
The actual use of %fs as the user space segment is already there in
0.01, but there was no 'set_fs()'. That was a simpler and more direct
time, and "get_fs()" looked like this back then:
#define _fs() ({ \
register unsigned short __res; \
__asm__("mov %%fs,%%ax":"=a" (__res):); \
__res;})
and all the setting was basically part of the kernel entry asm and. Lovely.
Linus
^ permalink raw reply
* Re: [PATCH 0/1] powerpc/numa: do not skip node 0 in lookup table
From: Daniel Henrique Barboza @ 2020-09-04 20:06 UTC (permalink / raw)
To: linuxppc-dev
In-Reply-To: <20200814203413.542050-1-danielhb413@gmail.com>
I discussed this a bit with Aneesh Kumar in IBM internal Slack, a few weeks
ago, and he informed me that that this patch does not make sense with the
design used by the kernel. The kernel will assume that, for node 0, all
associativity domains must also be zeroed. This is why node 0 is skipped
when creating the distance table.
This of course has consequences for QEMU, so based on that, I've adapted
the QEMU implementation to not touch node 0.
Daniel
On 8/14/20 5:34 PM, Daniel Henrique Barboza wrote:
> Hi,
>
> This is a simple fix that I made while testing NUMA changes
> I'm making in QEMU [1]. Setting any non-zero value to the
> associativity of NUMA node 0 has no impact in the output
> of 'numactl' because the distance_lookup_table is never
> initialized for node 0.
>
> Seeing through the LOPAPR spec and git history I found no
> technical reason to skip node 0, which makes me believe this is
> a bug that got under the radar up until now because no one
> attempted to set node 0 associativity like I'm doing now.
>
> For anyone wishing to give it a spin, using the QEMU build
> in [1] and experimenting with NUMA distances, such as:
>
> sudo ./qemu-system-ppc64 -machine pseries-5.2,accel=kvm,usb=off,dump-guest-core=off -m 65536 -overcommit mem-lock=off -smp 4,sockets=4,cores=1,threads=1 -rtc base=utc -display none -vga none -nographic -boot menu=on -device spapr-pci-host-bridge,index=1,id=pci.1 -device spapr-pci-host-bridge,index=2,id=pci.2 -device spapr-pci-host-bridge,index=3,id=pci.3 -device spapr-pci-host-bridge,index=4,id=pci.4 -device qemu-xhci,id=usb,bus=pci.0,addr=0x2 -drive file=/home/danielhb/f32.qcow2,format=qcow2,if=none,id=drive-virtio-disk0 -device virtio-blk-pci,scsi=off,bus=pci.0,addr=0x3,drive=drive-virtio-disk0,id=virtio-disk0,bootindex=1 -device usb-kbd,id=input0,bus=usb.0,port=1 -device usb-mouse,id=input1,bus=usb.0,port=2 -device virtio-balloon-pci,id=balloon0,bus=pci.0,addr=0x4 -msg timestamp=on \
> -numa node,nodeid=0,cpus=0 -numa node,nodeid=1,cpus=1 \
> -numa node,nodeid=2,cpus=2 -numa node,nodeid=3,cpus=3 \
> -numa dist,src=0,dst=1,val=80 -numa dist,src=0,dst=2,val=80 \
> -numa dist,src=0,dst=3,val=80 -numa dist,src=1,dst=2,val=80 \
> -numa dist,src=1,dst=3,val=80 -numa dist,src=2,dst=3,val=80
>
> The current kernel code will ignore the associativity of
> node 0, and numactl will output this:
>
> node distances:
> node 0 1 2 3
> 0: 10 160 160 160
> 1: 160 10 80 80
> 2: 160 80 10 80
> 3: 160 80 80 10
>
> With this patch:
>
> node distances:
> node 0 1 2 3
> 0: 10 160 160 160
> 1: 160 10 80 40
> 2: 160 80 10 20
> 3: 160 40 20 10
>
>
> If anyone wonders, this patch has no conflict with the proposed
> NUMA changes in [2] because Aneesh isn't changing this line.
>
>
> [1] https://github.com/danielhb/qemu/tree/spapr_numa_v1
> [2] https://patchwork.ozlabs.org/project/linuxppc-dev/patch/20200731111916.243569-1-aneesh.kumar@linux.ibm.com/
>
>
> Daniel Henrique Barboza (1):
> powerpc/numa: do not skip node 0 when init lookup table
>
> arch/powerpc/mm/numa.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
^ permalink raw reply
* RE: remove the last set_fs() in common code, and remove it for x86 and powerpc v3
From: David Laight @ 2020-09-04 21:01 UTC (permalink / raw)
To: 'Alexey Dobriyan', Ingo Molnar
Cc: linux-arch@vger.kernel.org, linuxppc-dev@lists.ozlabs.org,
Kees Cook, x86@kernel.org, linux-kernel@vger.kernel.org,
Luis Chamberlain, Al Viro, linux-fsdevel@vger.kernel.org,
Linus Torvalds, Christoph Hellwig
In-Reply-To: <20200904175823.GA500051@localhost.localdomain>
From: Alexey Dobriyan
> Sent: 04 September 2020 18:58
>
> On Fri, Sep 04, 2020 at 08:00:24AM +0200, Ingo Molnar wrote:
> > * Christoph Hellwig <hch@lst.de> wrote:
> > > this series removes the last set_fs() used to force a kernel address
> > > space for the uaccess code in the kernel read/write/splice code, and then
> > > stops implementing the address space overrides entirely for x86 and
> > > powerpc.
> >
> > Cool! For the x86 bits:
> >
> > Acked-by: Ingo Molnar <mingo@kernel.org>
>
> set_fs() is older than some kernel hackers!
>
> $ cd linux-0.11/
> $ find . -type f -name '*.h' | xargs grep -e set_fs -w -n -A3
> ./include/asm/segment.h:61:extern inline void set_fs(unsigned long val)
> ./include/asm/segment.h-62-{
> ./include/asm/segment.h-63- __asm__("mov %0,%%fs"::"a" ((unsigned short) val));
> ./include/asm/segment.h-64-}
What is this strange %fs register you are talking about.
Figure 2-4 only has CS, DS, SS and ES.
David
-
Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK
Registration No: 1397386 (Wales)
^ permalink raw reply
* [Bug 208181] BUG: KASAN: stack-out-of-bounds in strcmp+0x58/0xd8
From: bugzilla-daemon @ 2020-09-04 22:19 UTC (permalink / raw)
To: linuxppc-dev
In-Reply-To: <bug-208181-206035@https.bugzilla.kernel.org/>
https://bugzilla.kernel.org/show_bug.cgi?id=208181
--- Comment #17 from Erhard F. (erhard_f@mailbox.org) ---
Created attachment 292337
--> https://bugzilla.kernel.org/attachment.cgi?id=292337&action=edit
dmesg (5.9-rc3, INLINE KASAN, PowerMac G4 DP)
Re-tried with 5.9-rc3 (inline KASAN). The original problem (stack-out-of-bounds
in strcmp+0x58/0xd8) is gone, but still problems with stack usage when doing
larger build jobs:
[...]
[ 1929.683510] do_IRQ: stack overflow: 1696
[ 1929.690727] CPU: 1 PID: 735 Comm: mount.nfs Tainted: G W
5.9.0-rc3-PowerMacG4 #1
[ 1929.697847] Call Trace:
[ 1929.704633] [d0ca4670] [c0a75518] dump_stack+0xfc/0x130 (unreliable)
[ 1929.711507] [d0ca46a0] [c000b094] do_IRQ+0x128/0x180
[ 1929.717998] [d0ca46d0] [c002e560] ret_from_except+0x0/0x14
[ 1929.724652] --- interrupt: 501 at _raw_spin_unlock_irqrestore+0x3c/0xa4
LR = _raw_spin_unlock_irqrestore+0x38/0xa4
[ 1929.738722] [d0ca47b8] [c0a6dc90] stack_depot_save+0x20c/0x390
[ 1929.746132] [d0ca4818] [c04d4b70] kasan_save_stack+0x40/0x48
[ 1929.753675] [d0ca4928] [c04d4b9c] kasan_set_track+0x24/0x30
[ 1929.761298] [d0ca4938] [c04d710c] kasan_set_free_info+0x28/0x3c
[ 1929.769073] [d0ca4948] [c04d4f74] __kasan_slab_free+0x104/0x118
[ 1929.776983] [d0ca4968] [c04ce800] slab_free_freelist_hook+0xec/0x17c
[ 1929.785111] [d0ca49a8] [c04d3468] kmem_cache_free+0x58/0x2a0
[ 1929.793391] [d0ca49f8] [c11b251c] packet_rcv+0xb9c/0xbb4
[ 1929.801797] [d0ca4a48] [c0dbfd98] dev_queue_xmit_nit+0x6e4/0x748
[ 1929.810434] [d0ca4ab8] [c0dcaf80] dev_hard_start_xmit+0xec/0x880
[ 1929.819207] [d0ca4b18] [c0ea4814] sch_direct_xmit+0x1f8/0x818
[ 1929.828111] [d0ca4bf8] [c0dcc884] __dev_queue_xmit+0xed4/0x136c
[ 1929.837202] [d0ca4d28] [c0f256dc] ip_finish_output2+0xfcc/0x1028
[ 1929.846472] [d0ca4d88] [c0f2d848] __ip_queue_xmit+0xde0/0x1018
[ 1929.855892] [d0ca4df8] [c0f929d8] __tcp_transmit_skb+0x2550/0x2cb8
[ 1929.865486] [d0ca4ee8] [c0f98470] tcp_write_xmit+0x1d28/0x3498
[ 1929.875216] [d0ca4f78] [c0f99c8c] __tcp_push_pending_frames+0xac/0x1c4
[ 1929.885189] [d0ca4f98] [c0f5a970] tcp_sendmsg_locked+0x1c50/0x2294
[ 1929.895338] [d0ca5098] [c0f5afe4] tcp_sendmsg+0x30/0x48
[ 1929.905564] [d0ca50b8] [c0d598b0] sock_sendmsg_nosec+0xf4/0x10c
[ 1929.916463] [d0ca50d8] [b0a31840] xprt_sock_sendmsg+0x2c0/0x6e8 [sunrpc]
[ 1929.927494] [d0ca51b8] [b0a34ce8] xs_tcp_send_request+0x360/0x580 [sunrpc]
[ 1929.938699] [d0ca52e8] [b0a2eae8] xprt_transmit+0x4f8/0xe30 [sunrpc]
[ 1929.950044] [d0ca5368] [b0a1dcd8] call_transmit+0x238/0x25c [sunrpc]
[ 1929.961450] [d0ca5388] [b0a6641c] __rpc_execute+0x35c/0xbf8 [sunrpc]
[ 1929.972996] [d0ca5448] [b0a21d18] rpc_run_task+0x790/0x79c [sunrpc]
[ 1929.984850] [d0ca5498] [b1282e50] nfs4_call_sync_custom+0x14/0x80 [nfsv4]
[ 1929.996821] [d0ca54b8] [b128302c] nfs4_do_call_sync+0x170/0x1a8 [nfsv4]
[ 1930.008922] [d0ca55a8] [b12b3570] nfs4_proc_lookup_common+0x314/0xc54
[nfsv4]
[ 1930.020820] [d0ca5758] [b12b4244] nfs4_proc_lookup+0x158/0x2f0 [nfsv4]
[ 1930.032753] [d0ca57f8] [b0b49544] nfs_lookup+0x2ac/0x9ac [nfs]
[ 1930.044062] [d0ca5838] [c052c984] __lookup_slow+0x278/0x2a8
[ 1930.055461] [d0ca5958] [c05340a0] walk_component+0x288/0x30c
[ 1930.066816] [d0ca5a08] [c0534e5c] path_lookupat.isra.0+0x1b8/0x438
[ 1930.078282] [d0ca5a48] [c05372a0] filename_lookup+0x144/0x1c4
[ 1930.089834] [d0ca5b98] [c05373fc] vfs_path_lookup+0x94/0xc0
[ 1930.101389] [d0ca5c18] [c05714b8] mount_subtree+0x1c4/0x250
[ 1930.113267] [d0ca5ca8] [b12e1b2c] do_nfs4_mount+0x570/0x7fc [nfsv4]
[ 1930.125298] [d0ca5d68] [b12e202c] nfs4_try_get_tree+0xfc/0x16c [nfsv4]
[ 1930.137200] [d0ca5d88] [c050e434] vfs_get_tree+0xf8/0x398
[ 1930.149133] [d0ca5db8] [c056f968] path_mount+0x1074/0x113c
[ 1930.161107] [d0ca5e78] [c056fad8] do_mount+0xa8/0xe4
[ 1930.173109] [d0ca5f08] [c0570054] sys_mount+0xa8/0xb8
[ 1930.185160] [d0ca5f38] [c002e1cc] ret_from_syscall+0x0/0x34
[ 1930.197313] --- interrupt: c01 at 0x8b5754
LR = 0xac0be0
[ 1930.222896] Kernel panic - not syncing: corrupted stack end detected inside
scheduler
But feel free to close this bug if appropriate as the original issue is solved.
--
You are receiving this mail because:
You are watching the assignee of the bug.
^ permalink raw reply
* [Bug 208181] BUG: KASAN: stack-out-of-bounds in strcmp+0x58/0xd8
From: bugzilla-daemon @ 2020-09-04 22:21 UTC (permalink / raw)
To: linuxppc-dev
In-Reply-To: <bug-208181-206035@https.bugzilla.kernel.org/>
https://bugzilla.kernel.org/show_bug.cgi?id=208181
--- Comment #18 from Erhard F. (erhard_f@mailbox.org) ---
Created attachment 292339
--> https://bugzilla.kernel.org/attachment.cgi?id=292339&action=edit
kernel .config (5.9-rc3, PowerMac G4 DP)
--
You are receiving this mail because:
You are watching the assignee of the bug.
^ permalink raw reply
* [Bug 205099] KASAN hit at raid6_pq: BUG: Unable to handle kernel data access at 0x00f0fd0d
From: bugzilla-daemon @ 2020-09-04 22:50 UTC (permalink / raw)
To: linuxppc-dev
In-Reply-To: <bug-205099-206035@https.bugzilla.kernel.org/>
https://bugzilla.kernel.org/show_bug.cgi?id=205099
Erhard F. (erhard_f@mailbox.org) changed:
What |Removed |Added
----------------------------------------------------------------------------
Attachment #287625|0 |1
is obsolete| |
Attachment #288411|0 |1
is obsolete| |
--- Comment #30 from Erhard F. (erhard_f@mailbox.org) ---
Created attachment 292345
--> https://bugzilla.kernel.org/attachment.cgi?id=292345&action=edit
dmesg (5.9-rc3, OUTLINE KASAN, PowerMac G4 DP)
Re-tested with v5.9-rc3 out of curiosity. Not much change here, the bug shows
up with OUTLINE KASAN but not with INLINE KASAN, everything else being equal:
==================================================================
BUG: KASAN: user-memory-access in raid6_altivec8_gen_syndrome_real+0x2b0/0x480
[raid6_pq]
Read of size 4 at addr 5764b118 by task modprobe/126
CPU: 1 PID: 126 Comm: modprobe Tainted: G W 5.9.0-rc3-PowerMacG4
#2
Call Trace:
[e32cb7b8] [c0517aac] dump_stack+0xc4/0xf8 (unreliable)
[e32cb7e8] [c026e73c] kasan_report+0x16c/0x170
[e32cb828] [b02004e0] raid6_altivec8_gen_syndrome_real+0x2b0/0x480 [raid6_pq]
[e32cba18] [b02006fc] raid6_altivec8_gen_syndrome+0x4c/0x88 [raid6_pq]
[e32cba38] [b021a42c] init_module+0x42c/0x590 [raid6_pq]
[e32cbb08] [c00058a0] do_one_initcall+0xb8/0x3dc
[e32cbbd8] [c011c0fc] do_init_module+0xa8/0x2c4
[e32cbc08] [c011f02c] load_module+0x2b98/0x2d4c
[e32cbe18] [c011f448] sys_finit_module+0x100/0x138
[e32cbf38] [c001a1cc] ret_from_syscall+0x0/0x34
--- interrupt: c01 at 0x3d2068
LR = 0x506104
==================================================================
BUG: Unable to handle kernel data access on read at 0x5764b118
Faulting instruction address: 0xb02004e0
Oops: Kernel access of bad area, sig: 11 [#1]
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^ permalink raw reply
* [Bug 205099] KASAN hit at raid6_pq: BUG: Unable to handle kernel data access at 0x00f0fd0d
From: bugzilla-daemon @ 2020-09-04 22:54 UTC (permalink / raw)
To: linuxppc-dev
In-Reply-To: <bug-205099-206035@https.bugzilla.kernel.org/>
https://bugzilla.kernel.org/show_bug.cgi?id=205099
Erhard F. (erhard_f@mailbox.org) changed:
What |Removed |Added
----------------------------------------------------------------------------
Attachment #288413|0 |1
is obsolete| |
--- Comment #31 from Erhard F. (erhard_f@mailbox.org) ---
Created attachment 292347
--> https://bugzilla.kernel.org/attachment.cgi?id=292347&action=edit
kernel .config (5.9-rc3, OUTLINE KASAN, PowerMac G4 DP)
Does happen even if RAID support is not actively selected in the config as
btrfs pulls in RAID6_PQ on its own.
# CONFIG_DM_RAID is not set
CONFIG_RAID6_PQ=m
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^ permalink raw reply
* [Bug 208181] BUG: KASAN: stack-out-of-bounds in strcmp+0x58/0xd8
From: bugzilla-daemon @ 2020-09-04 22:57 UTC (permalink / raw)
To: linuxppc-dev
In-Reply-To: <bug-208181-206035@https.bugzilla.kernel.org/>
https://bugzilla.kernel.org/show_bug.cgi?id=208181
Erhard F. (erhard_f@mailbox.org) changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|NEW |RESOLVED
Resolution|--- |OBSOLETE
--- Comment #19 from Erhard F. (erhard_f@mailbox.org) ---
I noticed that I covered the "do_IRQ: stack overflow: ...." problem already in
bug #207129 so closing this one as suggested before.
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^ permalink raw reply
* [PATCH 0/5] powerpc/tau: TAU driver fixes
From: Finn Thain @ 2020-09-04 23:02 UTC (permalink / raw)
To: Michael Ellerman, Benjamin Herrenschmidt, Paul Mackerras
Cc: linuxppc-dev, linux-kernel
This patch series fixes various bugs in the Thermal Assist Unit driver.
It was tested on 266 MHz and 292 MHz PowerBook G3 laptops.
Finn Thain (5):
powerpc/tau: Use appropriate temperature sample interval
powerpc/tau: Convert from timer to workqueue
powerpc/tau: Remove duplicated set_thresholds() call
powerpc/tau: Check processor type before enabling TAU interrupt
powerpc/tau: Disable TAU between measurements
arch/powerpc/include/asm/reg.h | 2 +-
arch/powerpc/kernel/tau_6xx.c | 147 +++++++++++++--------------------
arch/powerpc/platforms/Kconfig | 14 +---
3 files changed, 62 insertions(+), 101 deletions(-)
--
2.26.2
^ permalink raw reply
* [PATCH 1/5] powerpc/tau: Use appropriate temperature sample interval
From: Finn Thain @ 2020-09-04 23:02 UTC (permalink / raw)
To: Michael Ellerman, Benjamin Herrenschmidt, Paul Mackerras
Cc: linuxppc-dev, linux-kernel
In-Reply-To: <cover.1599260540.git.fthain@telegraphics.com.au>
According to the MPC750 Users Manual, the SITV value in Thermal
Management Register 3 is 13 bits long. The present code calculates the
SITV value as 60 * 500 cycles. This would overflow to give 10 us on
a 500 MHz CPU rather than the intended 60 us. (But according to the
Microprocessor Datasheet, there is also a factor of 266 that has to be
applied to this value on certain parts i.e. speed sort above 266 MHz.)
Always use the maximum cycle count, as recommended by the Datasheet.
Fixes: 1da177e4c3f41 ("Linux-2.6.12-rc2")
Tested-by: Stan Johnson <userm57@yahoo.com>
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
---
arch/powerpc/include/asm/reg.h | 2 +-
arch/powerpc/kernel/tau_6xx.c | 12 ++++--------
2 files changed, 5 insertions(+), 9 deletions(-)
diff --git a/arch/powerpc/include/asm/reg.h b/arch/powerpc/include/asm/reg.h
index 88e6c78100d9b..c750afc62887c 100644
--- a/arch/powerpc/include/asm/reg.h
+++ b/arch/powerpc/include/asm/reg.h
@@ -815,7 +815,7 @@
#define THRM1_TIN (1 << 31)
#define THRM1_TIV (1 << 30)
#define THRM1_THRES(x) ((x&0x7f)<<23)
-#define THRM3_SITV(x) ((x&0x3fff)<<1)
+#define THRM3_SITV(x) ((x & 0x1fff) << 1)
#define THRM1_TID (1<<2)
#define THRM1_TIE (1<<1)
#define THRM1_V (1<<0)
diff --git a/arch/powerpc/kernel/tau_6xx.c b/arch/powerpc/kernel/tau_6xx.c
index e2ab8a111b693..976d5bc1b5176 100644
--- a/arch/powerpc/kernel/tau_6xx.c
+++ b/arch/powerpc/kernel/tau_6xx.c
@@ -178,15 +178,11 @@ static void tau_timeout(void * info)
* complex sleep code needs to be added. One mtspr every time
* tau_timeout is called is probably not a big deal.
*
- * Enable thermal sensor and set up sample interval timer
- * need 20 us to do the compare.. until a nice 'cpu_speed' function
- * call is implemented, just assume a 500 mhz clock. It doesn't really
- * matter if we take too long for a compare since it's all interrupt
- * driven anyway.
- *
- * use a extra long time.. (60 us @ 500 mhz)
+ * The "PowerPC 740 and PowerPC 750 Microprocessor Datasheet"
+ * recommends that "the maximum value be set in THRM3 under all
+ * conditions."
*/
- mtspr(SPRN_THRM3, THRM3_SITV(500*60) | THRM3_E);
+ mtspr(SPRN_THRM3, THRM3_SITV(0x1fff) | THRM3_E);
local_irq_restore(flags);
}
--
2.26.2
^ permalink raw reply related
* [PATCH 3/5] powerpc/tau: Remove duplicated set_thresholds() call
From: Finn Thain @ 2020-09-04 23:02 UTC (permalink / raw)
To: Michael Ellerman, Benjamin Herrenschmidt, Paul Mackerras
Cc: linuxppc-dev, linux-kernel
In-Reply-To: <cover.1599260540.git.fthain@telegraphics.com.au>
The commentary at the call site seems to disagree with the code. The
conditional prevents calling set_thresholds() via the exception handler,
which appears to crash. Perhaps that's because it immediately triggers
another TAU exception. Anyway, calling set_thresholds() from TAUupdate()
is redundant because tau_timeout() does so.
Fixes: 1da177e4c3f41 ("Linux-2.6.12-rc2")
Tested-by: Stan Johnson <userm57@yahoo.com>
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
---
arch/powerpc/kernel/tau_6xx.c | 5 -----
1 file changed, 5 deletions(-)
diff --git a/arch/powerpc/kernel/tau_6xx.c b/arch/powerpc/kernel/tau_6xx.c
index 268205cc347da..b8d7e7d498e0a 100644
--- a/arch/powerpc/kernel/tau_6xx.c
+++ b/arch/powerpc/kernel/tau_6xx.c
@@ -110,11 +110,6 @@ static void TAUupdate(int cpu)
#ifdef DEBUG
printk("grew = %d\n", tau[cpu].grew);
#endif
-
-#ifndef CONFIG_TAU_INT /* tau_timeout will do this if not using interrupts */
- set_thresholds(cpu);
-#endif
-
}
#ifdef CONFIG_TAU_INT
--
2.26.2
^ permalink raw reply related
* [PATCH 2/5] powerpc/tau: Convert from timer to workqueue
From: Finn Thain @ 2020-09-04 23:02 UTC (permalink / raw)
To: Michael Ellerman, Benjamin Herrenschmidt, Paul Mackerras
Cc: linuxppc-dev, linux-kernel
In-Reply-To: <cover.1599260540.git.fthain@telegraphics.com.au>
Since commit 19dbdcb8039cf ("smp: Warn on function calls from softirq
context") the Thermal Assist Unit driver causes a warning like the
following when CONFIG_SMP is enabled.
------------[ cut here ]------------
WARNING: CPU: 0 PID: 0 at kernel/smp.c:428 smp_call_function_many_cond+0xf4/0x38c
Modules linked in:
CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.7.0-pmac #3
NIP: c00b37a8 LR: c00b3abc CTR: c001218c
REGS: c0799c60 TRAP: 0700 Not tainted (5.7.0-pmac)
MSR: 00029032 <EE,ME,IR,DR,RI> CR: 42000224 XER: 00000000
GPR00: c00b3abc c0799d18 c076e300 c079ef5c c0011fec 00000000 00000000 00000000
GPR08: 00000100 00000100 00008000 ffffffff 42000224 00000000 c079d040 c079d044
GPR16: 00000001 00000000 00000004 c0799da0 c079f054 c07a0000 c07a0000 00000000
GPR24: c0011fec 00000000 c079ef5c c079ef5c 00000000 00000000 00000000 00000000
NIP [c00b37a8] smp_call_function_many_cond+0xf4/0x38c
LR [c00b3abc] on_each_cpu+0x38/0x68
Call Trace:
[c0799d18] [ffffffff] 0xffffffff (unreliable)
[c0799d68] [c00b3abc] on_each_cpu+0x38/0x68
[c0799d88] [c0096704] call_timer_fn.isra.26+0x20/0x7c
[c0799d98] [c0096b40] run_timer_softirq+0x1d4/0x3fc
[c0799df8] [c05b4368] __do_softirq+0x118/0x240
[c0799e58] [c0039c44] irq_exit+0xc4/0xcc
[c0799e68] [c000ade8] timer_interrupt+0x1b0/0x230
[c0799ea8] [c0013520] ret_from_except+0x0/0x14
--- interrupt: 901 at arch_cpu_idle+0x24/0x6c
LR = arch_cpu_idle+0x24/0x6c
[c0799f70] [00000001] 0x1 (unreliable)
[c0799f80] [c0060990] do_idle+0xd8/0x17c
[c0799fa0] [c0060ba8] cpu_startup_entry+0x24/0x28
[c0799fb0] [c072d220] start_kernel+0x434/0x44c
[c0799ff0] [00003860] 0x3860
Instruction dump:
8129f204 2f890000 40beff98 3d20c07a 8929eec4 2f890000 40beff88 0fe00000
81220000 552805de 550802ef 4182ff84 <0fe00000> 3860ffff 7f65db78 7f44d378
---[ end trace 34a886e47819c2eb ]---
Don't call on_each_cpu() from a timer callback, call it from a worker
thread instead.
Fixes: 1da177e4c3f41 ("Linux-2.6.12-rc2")
Tested-by: Stan Johnson <userm57@yahoo.com>
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
---
arch/powerpc/kernel/tau_6xx.c | 38 +++++++++++++++++------------------
1 file changed, 18 insertions(+), 20 deletions(-)
diff --git a/arch/powerpc/kernel/tau_6xx.c b/arch/powerpc/kernel/tau_6xx.c
index 976d5bc1b5176..268205cc347da 100644
--- a/arch/powerpc/kernel/tau_6xx.c
+++ b/arch/powerpc/kernel/tau_6xx.c
@@ -13,13 +13,14 @@
*/
#include <linux/errno.h>
-#include <linux/jiffies.h>
#include <linux/kernel.h>
#include <linux/param.h>
#include <linux/string.h>
#include <linux/mm.h>
#include <linux/interrupt.h>
#include <linux/init.h>
+#include <linux/delay.h>
+#include <linux/workqueue.h>
#include <asm/io.h>
#include <asm/reg.h>
@@ -39,8 +40,6 @@ static struct tau_temp
unsigned char grew;
} tau[NR_CPUS];
-struct timer_list tau_timer;
-
#undef DEBUG
/* TODO: put these in a /proc interface, with some sanity checks, and maybe
@@ -50,7 +49,7 @@ struct timer_list tau_timer;
#define step_size 2 /* step size when temp goes out of range */
#define window_expand 1 /* expand the window by this much */
/* configurable values for shrinking the window */
-#define shrink_timer 2*HZ /* period between shrinking the window */
+#define shrink_timer 2000 /* period between shrinking the window */
#define min_window 2 /* minimum window size, degrees C */
static void set_thresholds(unsigned long cpu)
@@ -187,14 +186,18 @@ static void tau_timeout(void * info)
local_irq_restore(flags);
}
-static void tau_timeout_smp(struct timer_list *unused)
-{
+static struct workqueue_struct *tau_workq;
- /* schedule ourselves to be run again */
- mod_timer(&tau_timer, jiffies + shrink_timer) ;
+static void tau_work_func(struct work_struct *work)
+{
+ msleep(shrink_timer);
on_each_cpu(tau_timeout, NULL, 0);
+ /* schedule ourselves to be run again */
+ queue_work(tau_workq, work);
}
+DECLARE_WORK(tau_work, tau_work_func);
+
/*
* setup the TAU
*
@@ -227,21 +230,16 @@ static int __init TAU_init(void)
return 1;
}
-
- /* first, set up the window shrinking timer */
- timer_setup(&tau_timer, tau_timeout_smp, 0);
- tau_timer.expires = jiffies + shrink_timer;
- add_timer(&tau_timer);
+ tau_workq = alloc_workqueue("tau", WQ_UNBOUND, 1, 0);
+ if (!tau_workq)
+ return -ENOMEM;
on_each_cpu(TAU_init_smp, NULL, 0);
- printk("Thermal assist unit ");
-#ifdef CONFIG_TAU_INT
- printk("using interrupts, ");
-#else
- printk("using timers, ");
-#endif
- printk("shrink_timer: %d jiffies\n", shrink_timer);
+ queue_work(tau_workq, &tau_work);
+
+ pr_info("Thermal assist unit using %s, shrink_timer: %d ms\n",
+ IS_ENABLED(CONFIG_TAU_INT) ? "interrupts" : "workqueue", shrink_timer);
tau_initialized = 1;
return 0;
--
2.26.2
^ permalink raw reply related
* [PATCH 4/5] powerpc/tau: Check processor type before enabling TAU interrupt
From: Finn Thain @ 2020-09-04 23:02 UTC (permalink / raw)
To: Michael Ellerman, Benjamin Herrenschmidt, Paul Mackerras
Cc: linuxppc-dev, linux-kernel
In-Reply-To: <cover.1599260540.git.fthain@telegraphics.com.au>
According to Freescale's documentation, MPC74XX processors have an
erratum that prevents the TAU interrupt from working, so don't try to
use it when running on those processors.
Fixes: 1da177e4c3f41 ("Linux-2.6.12-rc2")
Tested-by: Stan Johnson <userm57@yahoo.com>
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
---
arch/powerpc/kernel/tau_6xx.c | 33 ++++++++++++++-------------------
arch/powerpc/platforms/Kconfig | 5 ++---
2 files changed, 16 insertions(+), 22 deletions(-)
diff --git a/arch/powerpc/kernel/tau_6xx.c b/arch/powerpc/kernel/tau_6xx.c
index b8d7e7d498e0a..614b5b272d9c6 100644
--- a/arch/powerpc/kernel/tau_6xx.c
+++ b/arch/powerpc/kernel/tau_6xx.c
@@ -40,6 +40,8 @@ static struct tau_temp
unsigned char grew;
} tau[NR_CPUS];
+static bool tau_int_enable;
+
#undef DEBUG
/* TODO: put these in a /proc interface, with some sanity checks, and maybe
@@ -54,22 +56,13 @@ static struct tau_temp
static void set_thresholds(unsigned long cpu)
{
-#ifdef CONFIG_TAU_INT
- /*
- * setup THRM1,
- * threshold, valid bit, enable interrupts, interrupt when below threshold
- */
- mtspr(SPRN_THRM1, THRM1_THRES(tau[cpu].low) | THRM1_V | THRM1_TIE | THRM1_TID);
+ u32 maybe_tie = tau_int_enable ? THRM1_TIE : 0;
- /* setup THRM2,
- * threshold, valid bit, enable interrupts, interrupt when above threshold
- */
- mtspr (SPRN_THRM2, THRM1_THRES(tau[cpu].high) | THRM1_V | THRM1_TIE);
-#else
- /* same thing but don't enable interrupts */
- mtspr(SPRN_THRM1, THRM1_THRES(tau[cpu].low) | THRM1_V | THRM1_TID);
- mtspr(SPRN_THRM2, THRM1_THRES(tau[cpu].high) | THRM1_V);
-#endif
+ /* setup THRM1, threshold, valid bit, interrupt when below threshold */
+ mtspr(SPRN_THRM1, THRM1_THRES(tau[cpu].low) | THRM1_V | maybe_tie | THRM1_TID);
+
+ /* setup THRM2, threshold, valid bit, interrupt when above threshold */
+ mtspr(SPRN_THRM2, THRM1_THRES(tau[cpu].high) | THRM1_V | maybe_tie);
}
static void TAUupdate(int cpu)
@@ -142,9 +135,8 @@ static void tau_timeout(void * info)
local_irq_save(flags);
cpu = smp_processor_id();
-#ifndef CONFIG_TAU_INT
- TAUupdate(cpu);
-#endif
+ if (!tau_int_enable)
+ TAUupdate(cpu);
size = tau[cpu].high - tau[cpu].low;
if (size > min_window && ! tau[cpu].grew) {
@@ -225,6 +217,9 @@ static int __init TAU_init(void)
return 1;
}
+ tau_int_enable = IS_ENABLED(CONFIG_TAU_INT) &&
+ !strcmp(cur_cpu_spec->platform, "ppc750");
+
tau_workq = alloc_workqueue("tau", WQ_UNBOUND, 1, 0);
if (!tau_workq)
return -ENOMEM;
@@ -234,7 +229,7 @@ static int __init TAU_init(void)
queue_work(tau_workq, &tau_work);
pr_info("Thermal assist unit using %s, shrink_timer: %d ms\n",
- IS_ENABLED(CONFIG_TAU_INT) ? "interrupts" : "workqueue", shrink_timer);
+ tau_int_enable ? "interrupts" : "workqueue", shrink_timer);
tau_initialized = 1;
return 0;
diff --git a/arch/powerpc/platforms/Kconfig b/arch/powerpc/platforms/Kconfig
index fb7515b4fa9c6..9fe36f0b54c1a 100644
--- a/arch/powerpc/platforms/Kconfig
+++ b/arch/powerpc/platforms/Kconfig
@@ -223,9 +223,8 @@ config TAU
temperature within 2-4 degrees Celsius. This option shows the current
on-die temperature in /proc/cpuinfo if the cpu supports it.
- Unfortunately, on some chip revisions, this sensor is very inaccurate
- and in many cases, does not work at all, so don't assume the cpu
- temp is actually what /proc/cpuinfo says it is.
+ Unfortunately, this sensor is very inaccurate when uncalibrated, so
+ don't assume the cpu temp is actually what /proc/cpuinfo says it is.
config TAU_INT
bool "Interrupt driven TAU driver (DANGEROUS)"
--
2.26.2
^ permalink raw reply related
* [PATCH 5/5] powerpc/tau: Disable TAU between measurements
From: Finn Thain @ 2020-09-04 23:02 UTC (permalink / raw)
To: Michael Ellerman, Benjamin Herrenschmidt, Paul Mackerras
Cc: linuxppc-dev, linux-kernel
In-Reply-To: <cover.1599260540.git.fthain@telegraphics.com.au>
Enabling CONFIG_TAU_INT causes random crashes:
Unrecoverable exception 1700 at c0009414 (msr=1000)
Oops: Unrecoverable exception, sig: 6 [#1]
BE PAGE_SIZE=4K MMU=Hash SMP NR_CPUS=2 PowerMac
Modules linked in:
CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.7.0-pmac-00043-gd5f545e1a8593 #5
NIP: c0009414 LR: c0009414 CTR: c00116fc
REGS: c0799eb8 TRAP: 1700 Not tainted (5.7.0-pmac-00043-gd5f545e1a8593)
MSR: 00001000 <ME> CR: 22000228 XER: 00000100
GPR00: 00000000 c0799f70 c076e300 00800000 0291c0ac 00e00000 c076e300 00049032
GPR08: 00000001 c00116fc 00000000 dfbd3200 ffffffff 007f80a8 00000000 00000000
GPR16: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 c075ce04
GPR24: c075ce04 dfff8880 c07b0000 c075ce04 00080000 00000001 c079ef98 c079ef5c
NIP [c0009414] arch_cpu_idle+0x24/0x6c
LR [c0009414] arch_cpu_idle+0x24/0x6c
Call Trace:
[c0799f70] [00000001] 0x1 (unreliable)
[c0799f80] [c0060990] do_idle+0xd8/0x17c
[c0799fa0] [c0060ba4] cpu_startup_entry+0x20/0x28
[c0799fb0] [c072d220] start_kernel+0x434/0x44c
[c0799ff0] [00003860] 0x3860
Instruction dump:
XXXXXXXX XXXXXXXX XXXXXXXX 3d20c07b XXXXXXXX XXXXXXXX XXXXXXXX 7c0802a6
XXXXXXXX XXXXXXXX XXXXXXXX 4e800421 XXXXXXXX XXXXXXXX XXXXXXXX 7d2000a6
---[ end trace 3a0c9b5cb216db6b ]---
Resolve this problem by disabling each THRMn comparator when handling
the associated THRMn interrupt and by disabling the TAU entirely when
updating THRMn thresholds.
Fixes: 1da177e4c3f41 ("Linux-2.6.12-rc2")
Tested-by: Stan Johnson <userm57@yahoo.com>
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
---
arch/powerpc/kernel/tau_6xx.c | 65 +++++++++++++---------------------
arch/powerpc/platforms/Kconfig | 9 ++---
2 files changed, 26 insertions(+), 48 deletions(-)
diff --git a/arch/powerpc/kernel/tau_6xx.c b/arch/powerpc/kernel/tau_6xx.c
index 614b5b272d9c6..0b4694b8d2482 100644
--- a/arch/powerpc/kernel/tau_6xx.c
+++ b/arch/powerpc/kernel/tau_6xx.c
@@ -42,8 +42,6 @@ static struct tau_temp
static bool tau_int_enable;
-#undef DEBUG
-
/* TODO: put these in a /proc interface, with some sanity checks, and maybe
* dynamic adjustment to minimize # of interrupts */
/* configurable values for step size and how much to expand the window when
@@ -67,42 +65,33 @@ static void set_thresholds(unsigned long cpu)
static void TAUupdate(int cpu)
{
- unsigned thrm;
-
-#ifdef DEBUG
- printk("TAUupdate ");
-#endif
+ u32 thrm;
+ u32 bits = THRM1_TIV | THRM1_TIN | THRM1_V;
/* if both thresholds are crossed, the step_sizes cancel out
* and the window winds up getting expanded twice. */
- if((thrm = mfspr(SPRN_THRM1)) & THRM1_TIV){ /* is valid? */
- if(thrm & THRM1_TIN){ /* crossed low threshold */
- if (tau[cpu].low >= step_size){
- tau[cpu].low -= step_size;
- tau[cpu].high -= (step_size - window_expand);
- }
- tau[cpu].grew = 1;
-#ifdef DEBUG
- printk("low threshold crossed ");
-#endif
+ thrm = mfspr(SPRN_THRM1);
+ if ((thrm & bits) == bits) {
+ mtspr(SPRN_THRM1, 0);
+
+ if (tau[cpu].low >= step_size) {
+ tau[cpu].low -= step_size;
+ tau[cpu].high -= (step_size - window_expand);
}
+ tau[cpu].grew = 1;
+ pr_debug("%s: low threshold crossed\n", __func__);
}
- if((thrm = mfspr(SPRN_THRM2)) & THRM1_TIV){ /* is valid? */
- if(thrm & THRM1_TIN){ /* crossed high threshold */
- if (tau[cpu].high <= 127-step_size){
- tau[cpu].low += (step_size - window_expand);
- tau[cpu].high += step_size;
- }
- tau[cpu].grew = 1;
-#ifdef DEBUG
- printk("high threshold crossed ");
-#endif
+ thrm = mfspr(SPRN_THRM2);
+ if ((thrm & bits) == bits) {
+ mtspr(SPRN_THRM2, 0);
+
+ if (tau[cpu].high <= 127 - step_size) {
+ tau[cpu].low += (step_size - window_expand);
+ tau[cpu].high += step_size;
}
+ tau[cpu].grew = 1;
+ pr_debug("%s: high threshold crossed\n", __func__);
}
-
-#ifdef DEBUG
- printk("grew = %d\n", tau[cpu].grew);
-#endif
}
#ifdef CONFIG_TAU_INT
@@ -127,17 +116,17 @@ void TAUException(struct pt_regs * regs)
static void tau_timeout(void * info)
{
int cpu;
- unsigned long flags;
int size;
int shrink;
- /* disabling interrupts *should* be okay */
- local_irq_save(flags);
cpu = smp_processor_id();
if (!tau_int_enable)
TAUupdate(cpu);
+ /* Stop thermal sensor comparisons and interrupts */
+ mtspr(SPRN_THRM3, 0);
+
size = tau[cpu].high - tau[cpu].low;
if (size > min_window && ! tau[cpu].grew) {
/* do an exponential shrink of half the amount currently over size */
@@ -159,18 +148,12 @@ static void tau_timeout(void * info)
set_thresholds(cpu);
- /*
- * Do the enable every time, since otherwise a bunch of (relatively)
- * complex sleep code needs to be added. One mtspr every time
- * tau_timeout is called is probably not a big deal.
- *
+ /* Restart thermal sensor comparisons and interrupts.
* The "PowerPC 740 and PowerPC 750 Microprocessor Datasheet"
* recommends that "the maximum value be set in THRM3 under all
* conditions."
*/
mtspr(SPRN_THRM3, THRM3_SITV(0x1fff) | THRM3_E);
-
- local_irq_restore(flags);
}
static struct workqueue_struct *tau_workq;
diff --git a/arch/powerpc/platforms/Kconfig b/arch/powerpc/platforms/Kconfig
index 9fe36f0b54c1a..b439b027a42f1 100644
--- a/arch/powerpc/platforms/Kconfig
+++ b/arch/powerpc/platforms/Kconfig
@@ -227,7 +227,7 @@ config TAU
don't assume the cpu temp is actually what /proc/cpuinfo says it is.
config TAU_INT
- bool "Interrupt driven TAU driver (DANGEROUS)"
+ bool "Interrupt driven TAU driver (EXPERIMENTAL)"
depends on TAU
help
The TAU supports an interrupt driven mode which causes an interrupt
@@ -235,12 +235,7 @@ config TAU_INT
to get notified the temp has exceeded a range. With this option off,
a timer is used to re-check the temperature periodically.
- However, on some cpus it appears that the TAU interrupt hardware
- is buggy and can cause a situation which would lead unexplained hard
- lockups.
-
- Unless you are extending the TAU driver, or enjoy kernel/hardware
- debugging, leave this option off.
+ If in doubt, say N here.
config TAU_AVERAGE
bool "Average high and low temp"
--
2.26.2
^ permalink raw reply related
* [PATCH v3 1/2] scsi: ibmvfc: use compiler attribute defines instead of __attribute__()
From: Tyrel Datwyler @ 2020-09-04 23:29 UTC (permalink / raw)
To: james.bottomley
Cc: Tyrel Datwyler, martin.petersen, linux-scsi, linux-kernel, brking,
linuxppc-dev
Update ibmvfc.h structs to use the preferred __packed and __aligned()
attribute macros defined in include/linux/compiler_attributes.h in place
of __attribute__().
Signed-off-by: Tyrel Datwyler <tyreld@linux.ibm.com>
---
drivers/scsi/ibmvscsi/ibmvfc.h | 56 +++++++++++++++++-----------------
1 file changed, 28 insertions(+), 28 deletions(-)
diff --git a/drivers/scsi/ibmvscsi/ibmvfc.h b/drivers/scsi/ibmvscsi/ibmvfc.h
index 907889f1fa9d..6da23666f5be 100644
--- a/drivers/scsi/ibmvscsi/ibmvfc.h
+++ b/drivers/scsi/ibmvscsi/ibmvfc.h
@@ -133,16 +133,16 @@ struct ibmvfc_mad_common {
__be16 status;
__be16 length;
__be64 tag;
-}__attribute__((packed, aligned (8)));
+} __packed __aligned(8);
struct ibmvfc_npiv_login_mad {
struct ibmvfc_mad_common common;
struct srp_direct_buf buffer;
-}__attribute__((packed, aligned (8)));
+} __packed __aligned(8);
struct ibmvfc_npiv_logout_mad {
struct ibmvfc_mad_common common;
-}__attribute__((packed, aligned (8)));
+} __packed __aligned(8);
#define IBMVFC_MAX_NAME 256
@@ -168,7 +168,7 @@ struct ibmvfc_npiv_login {
u8 device_name[IBMVFC_MAX_NAME];
u8 drc_name[IBMVFC_MAX_NAME];
__be64 reserved2[2];
-}__attribute__((packed, aligned (8)));
+} __packed __aligned(8);
struct ibmvfc_common_svc_parms {
__be16 fcph_version;
@@ -177,7 +177,7 @@ struct ibmvfc_common_svc_parms {
__be16 bb_rcv_sz; /* upper nibble is BB_SC_N */
__be32 ratov;
__be32 edtov;
-}__attribute__((packed, aligned (4)));
+} __packed __aligned(4);
struct ibmvfc_service_parms {
struct ibmvfc_common_svc_parms common;
@@ -192,7 +192,7 @@ struct ibmvfc_service_parms {
__be32 ext_len;
__be32 reserved[30];
__be32 clk_sync_qos[2];
-}__attribute__((packed, aligned (4)));
+} __packed __aligned(4);
struct ibmvfc_npiv_login_resp {
__be32 version;
@@ -217,12 +217,12 @@ struct ibmvfc_npiv_login_resp {
u8 drc_name[IBMVFC_MAX_NAME];
struct ibmvfc_service_parms service_parms;
__be64 reserved2;
-}__attribute__((packed, aligned (8)));
+} __packed __aligned(8);
union ibmvfc_npiv_login_data {
struct ibmvfc_npiv_login login;
struct ibmvfc_npiv_login_resp resp;
-}__attribute__((packed, aligned (8)));
+} __packed __aligned(8);
struct ibmvfc_discover_targets_buf {
__be32 scsi_id[1];
@@ -239,7 +239,7 @@ struct ibmvfc_discover_targets {
__be32 num_avail;
__be32 num_written;
__be64 reserved[2];
-}__attribute__((packed, aligned (8)));
+} __packed __aligned(8);
enum ibmvfc_fc_reason {
IBMVFC_INVALID_ELS_CMD_CODE = 0x01,
@@ -283,7 +283,7 @@ struct ibmvfc_port_login {
struct ibmvfc_service_parms service_parms;
struct ibmvfc_service_parms service_parms_change;
__be64 reserved3[2];
-}__attribute__((packed, aligned (8)));
+} __packed __aligned(8);
struct ibmvfc_prli_svc_parms {
u8 type;
@@ -303,7 +303,7 @@ struct ibmvfc_prli_svc_parms {
#define IBMVFC_PRLI_TARGET_FUNC 0x00000010
#define IBMVFC_PRLI_READ_FCP_XFER_RDY_DISABLED 0x00000002
#define IBMVFC_PRLI_WR_FCP_XFER_RDY_DISABLED 0x00000001
-}__attribute__((packed, aligned (4)));
+} __packed __aligned(4);
struct ibmvfc_process_login {
struct ibmvfc_mad_common common;
@@ -314,7 +314,7 @@ struct ibmvfc_process_login {
__be16 error; /* also fc_reason */
__be32 reserved2;
__be64 reserved3[2];
-}__attribute__((packed, aligned (8)));
+} __packed __aligned(8);
struct ibmvfc_query_tgt {
struct ibmvfc_mad_common common;
@@ -325,13 +325,13 @@ struct ibmvfc_query_tgt {
__be16 fc_explain;
__be16 fc_type;
__be64 reserved[2];
-}__attribute__((packed, aligned (8)));
+} __packed __aligned(8);
struct ibmvfc_implicit_logout {
struct ibmvfc_mad_common common;
__be64 old_scsi_id;
__be64 reserved[2];
-}__attribute__((packed, aligned (8)));
+} __packed __aligned(8);
struct ibmvfc_tmf {
struct ibmvfc_mad_common common;
@@ -348,7 +348,7 @@ struct ibmvfc_tmf {
__be32 my_cancel_key;
__be32 pad;
__be64 reserved[2];
-}__attribute__((packed, aligned (8)));
+} __packed __aligned(8);
enum ibmvfc_fcp_rsp_info_codes {
RSP_NO_FAILURE = 0x00,
@@ -361,7 +361,7 @@ struct ibmvfc_fcp_rsp_info {
u8 reserved[3];
u8 rsp_code;
u8 reserved2[4];
-}__attribute__((packed, aligned (2)));
+} __packed __aligned(2);
enum ibmvfc_fcp_rsp_flags {
FCP_BIDI_RSP = 0x80,
@@ -377,7 +377,7 @@ enum ibmvfc_fcp_rsp_flags {
union ibmvfc_fcp_rsp_data {
struct ibmvfc_fcp_rsp_info info;
u8 sense[SCSI_SENSE_BUFFERSIZE + sizeof(struct ibmvfc_fcp_rsp_info)];
-}__attribute__((packed, aligned (8)));
+} __packed __aligned(8);
struct ibmvfc_fcp_rsp {
__be64 reserved;
@@ -388,7 +388,7 @@ struct ibmvfc_fcp_rsp {
__be32 fcp_sense_len;
__be32 fcp_rsp_len;
union ibmvfc_fcp_rsp_data data;
-}__attribute__((packed, aligned (8)));
+} __packed __aligned(8);
enum ibmvfc_cmd_flags {
IBMVFC_SCATTERLIST = 0x0001,
@@ -422,7 +422,7 @@ struct ibmvfc_fcp_cmd_iu {
#define IBMVFC_WRDATA 0x01
u8 cdb[IBMVFC_MAX_CDB_LEN];
__be32 xfer_len;
-}__attribute__((packed, aligned (4)));
+} __packed __aligned(4);
struct ibmvfc_cmd {
__be64 task_tag;
@@ -446,7 +446,7 @@ struct ibmvfc_cmd {
__be64 reserved3[2];
struct ibmvfc_fcp_cmd_iu iu;
struct ibmvfc_fcp_rsp rsp;
-}__attribute__((packed, aligned (8)));
+} __packed __aligned(8);
struct ibmvfc_passthru_fc_iu {
__be32 payload[7];
@@ -473,18 +473,18 @@ struct ibmvfc_passthru_iu {
__be64 scsi_id;
__be64 tag;
__be64 reserved2[2];
-}__attribute__((packed, aligned (8)));
+} __packed __aligned(8);
struct ibmvfc_passthru_mad {
struct ibmvfc_mad_common common;
struct srp_direct_buf cmd_ioba;
struct ibmvfc_passthru_iu iu;
struct ibmvfc_passthru_fc_iu fc_iu;
-}__attribute__((packed, aligned (8)));
+} __packed __aligned(8);
struct ibmvfc_trace_start_entry {
u32 xfer_len;
-}__attribute__((packed));
+} __packed;
struct ibmvfc_trace_end_entry {
u16 status;
@@ -493,7 +493,7 @@ struct ibmvfc_trace_end_entry {
u8 rsp_code;
u8 scsi_status;
u8 reserved;
-}__attribute__((packed));
+} __packed;
struct ibmvfc_trace_entry {
struct ibmvfc_event *evt;
@@ -510,7 +510,7 @@ struct ibmvfc_trace_entry {
struct ibmvfc_trace_start_entry start;
struct ibmvfc_trace_end_entry end;
} u;
-}__attribute__((packed, aligned (8)));
+} __packed __aligned(8);
enum ibmvfc_crq_formats {
IBMVFC_CMD_FORMAT = 0x01,
@@ -545,7 +545,7 @@ struct ibmvfc_crq {
volatile u8 format;
u8 reserved[6];
volatile __be64 ioba;
-}__attribute__((packed, aligned (8)));
+} __packed __aligned(8);
struct ibmvfc_crq_queue {
struct ibmvfc_crq *msgs;
@@ -570,7 +570,7 @@ struct ibmvfc_async_crq {
volatile __be64 wwpn;
volatile __be64 node_name;
__be64 reserved;
-}__attribute__((packed, aligned (8)));
+} __packed __aligned(8);
struct ibmvfc_async_crq_queue {
struct ibmvfc_async_crq *msgs;
@@ -590,7 +590,7 @@ union ibmvfc_iu {
struct ibmvfc_tmf tmf;
struct ibmvfc_cmd cmd;
struct ibmvfc_passthru_mad passthru;
-}__attribute__((packed, aligned (8)));
+} __packed __aligned(8);
enum ibmvfc_target_action {
IBMVFC_TGT_ACTION_NONE = 0,
--
2.27.0
^ permalink raw reply related
* [PATCH v3 2/2] scsi: ibmvfc: interface updates for future FPIN and MQ support
From: Tyrel Datwyler @ 2020-09-04 23:29 UTC (permalink / raw)
To: james.bottomley
Cc: Tyrel Datwyler, martin.petersen, linux-scsi, linux-kernel, brking,
linuxppc-dev
In-Reply-To: <20200904232936.840193-1-tyreld@linux.ibm.com>
VIOS partitions with SLI-4 enabled Emulex adapters will be capable of
driving IO in parallel through mulitple work queues or channels, and
with new hyperviosr firmware that supports multiple interrupt sources
an ibmvfc NPIV single initiator can be modified to exploit end to end
channelization in a PowerVM environment.
VIOS hosts will also be able to expose fabric perfromance impact
notifications (FPIN) via a new asynchronous event to ibmvfc clients that
advertise support via IBMVFC_CAN_HANDLE_FPIN in their capabilities flag
during NPIV_LOGIN.
This patch introduces three new Management Datagrams (MADs) for
channelization support negotiation as well as the FPIN asynchronous
event and FPIN status flags. Follow up work is required to plumb the
ibmvfc client driver to use these new interfaces.
Signed-off-by: Tyrel Datwyler <tyreld@linux.ibm.com>
---
v2 -> v3:
Fixup checkpatch warnings about using __attribute__()
v1 -> v2:
Fixup complier errors from neglected commit --amend
---
drivers/scsi/ibmvscsi/ibmvfc.h | 66 +++++++++++++++++++++++++++++++++-
1 file changed, 65 insertions(+), 1 deletion(-)
diff --git a/drivers/scsi/ibmvscsi/ibmvfc.h b/drivers/scsi/ibmvscsi/ibmvfc.h
index 6da23666f5be..e6e1c255a79c 100644
--- a/drivers/scsi/ibmvscsi/ibmvfc.h
+++ b/drivers/scsi/ibmvscsi/ibmvfc.h
@@ -124,6 +124,9 @@ enum ibmvfc_mad_types {
IBMVFC_PASSTHRU = 0x0200,
IBMVFC_TMF_MAD = 0x0100,
IBMVFC_NPIV_LOGOUT = 0x0800,
+ IBMVFC_CHANNEL_ENQUIRY = 0x1000,
+ IBMVFC_CHANNEL_SETUP = 0x2000,
+ IBMVFC_CONNECTION_INFO = 0x4000,
};
struct ibmvfc_mad_common {
@@ -162,6 +165,8 @@ struct ibmvfc_npiv_login {
__be32 max_cmds;
__be64 capabilities;
#define IBMVFC_CAN_MIGRATE 0x01
+#define IBMVFC_CAN_USE_CHANNELS 0x02
+#define IBMVFC_CAN_HANDLE_FPIN 0x04
__be64 node_name;
struct srp_direct_buf async;
u8 partition_name[IBMVFC_MAX_NAME];
@@ -204,6 +209,7 @@ struct ibmvfc_npiv_login_resp {
__be64 capabilities;
#define IBMVFC_CAN_FLUSH_ON_HALT 0x08
#define IBMVFC_CAN_SUPPRESS_ABTS 0x10
+#define IBMVFC_CAN_SUPPORT_CHANNELS 0x20
__be32 max_cmds;
__be32 scsi_id_sz;
__be64 max_dma_len;
@@ -482,6 +488,52 @@ struct ibmvfc_passthru_mad {
struct ibmvfc_passthru_fc_iu fc_iu;
} __packed __aligned(8);
+struct ibmvfc_channel_enquiry {
+ struct ibmvfc_mad_common common;
+ __be32 flags;
+#define IBMVFC_NO_CHANNELS_TO_CRQ_SUPPORT 0x01
+#define IBMVFC_SUPPORT_VARIABLE_SUBQ_MSG 0x02
+#define IBMVFC_NO_N_TO_M_CHANNELS_SUPPORT 0x04
+ __be32 num_scsi_subq_channels;
+ __be32 num_nvmeof_subq_channels;
+ __be32 num_scsi_vas_channels;
+ __be32 num_nvmeof_vas_channels;
+} __packed __aligned(8);
+
+struct ibmvfc_channel_setup_mad {
+ struct ibmvfc_mad_common common;
+ struct srp_direct_buf buffer;
+} __packed __aligned(8);
+
+#define IBMVFC_MAX_CHANNELS 502
+
+struct ibmvfc_channel_setup {
+ __be32 flags;
+#define IBMVFC_CANCEL_CHANNELS 0x01
+#define IBMVFC_USE_BUFFER 0x02
+#define IBMVFC_CHANNELS_CANCELED 0x04
+ __be32 reserved;
+ __be32 num_scsi_subq_channels;
+ __be32 num_nvmeof_subq_channels;
+ __be32 num_scsi_vas_channels;
+ __be32 num_nvmeof_vas_channels;
+ struct srp_direct_buf buffer;
+ __be64 reserved2[5];
+ __be64 channel_handles[IBMVFC_MAX_CHANNELS];
+} __packed __aligned(8);
+
+struct ibmvfc_connection_info {
+ struct ibmvfc_mad_common common;
+ __be64 information_bits;
+#define IBMVFC_NO_FC_IO_CHANNEL 0x01
+#define IBMVFC_NO_PHYP_VAS 0x02
+#define IBMVFC_NO_PHYP_SUBQ 0x04
+#define IBMVFC_PHYP_DEPRECATED_SUBQ 0x08
+#define IBMVFC_PHYP_PRESERVED_SUBQ 0x10
+#define IBMVFC_PHYP_FULL_SUBQ 0x20
+ __be64 reserved[16];
+} __packed __aligned(8);
+
struct ibmvfc_trace_start_entry {
u32 xfer_len;
} __packed;
@@ -532,6 +584,7 @@ enum ibmvfc_async_event {
IBMVFC_AE_HALT = 0x0400,
IBMVFC_AE_RESUME = 0x0800,
IBMVFC_AE_ADAPTER_FAILED = 0x1000,
+ IBMVFC_AE_FPIN = 0x2000,
};
struct ibmvfc_async_desc {
@@ -560,10 +613,18 @@ enum ibmvfc_ae_link_state {
IBMVFC_AE_LS_LINK_DEAD = 0x08,
};
+enum ibmvfc_ae_fpin_status {
+ IBMVFC_AE_FPIN_LINK_CONGESTED = 0x1,
+ IBMVFC_AE_FPIN_PORT_CONGESTED = 0x2,
+ IBMVFC_AE_FPIN_PORT_CLEARED = 0x3,
+ IBMVFC_AE_FPIN_PORT_DEGRADED = 0x4,
+};
+
struct ibmvfc_async_crq {
volatile u8 valid;
u8 link_state;
- u8 pad[2];
+ u8 fpin_status;
+ u8 pad;
__be32 pad2;
volatile __be64 event;
volatile __be64 scsi_id;
@@ -590,6 +651,9 @@ union ibmvfc_iu {
struct ibmvfc_tmf tmf;
struct ibmvfc_cmd cmd;
struct ibmvfc_passthru_mad passthru;
+ struct ibmvfc_channel_enquiry channel_enquiry;
+ struct ibmvfc_channel_setup_mad channel_setup;
+ struct ibmvfc_connection_info connection_info;
} __packed __aligned(8);
enum ibmvfc_target_action {
--
2.27.0
^ permalink raw reply related
* Re: remove the last set_fs() in common code, and remove it for x86 and powerpc v3
From: Christophe Leroy @ 2020-09-05 7:16 UTC (permalink / raw)
To: David Laight, 'Alexey Dobriyan', Ingo Molnar
Cc: linux-arch@vger.kernel.org, Kees Cook, Linus Torvalds,
x86@kernel.org, linux-kernel@vger.kernel.org, Luis Chamberlain,
Al Viro, linux-fsdevel@vger.kernel.org,
linuxppc-dev@lists.ozlabs.org, Christoph Hellwig
In-Reply-To: <63f3c9342a784a0890b3b641a71a8aa1@AcuMS.aculab.com>
Le 04/09/2020 à 23:01, David Laight a écrit :
> From: Alexey Dobriyan
>> Sent: 04 September 2020 18:58
>>
>> On Fri, Sep 04, 2020 at 08:00:24AM +0200, Ingo Molnar wrote:
>>> * Christoph Hellwig <hch@lst.de> wrote:
>>>> this series removes the last set_fs() used to force a kernel address
>>>> space for the uaccess code in the kernel read/write/splice code, and then
>>>> stops implementing the address space overrides entirely for x86 and
>>>> powerpc.
>>>
>>> Cool! For the x86 bits:
>>>
>>> Acked-by: Ingo Molnar <mingo@kernel.org>
>>
>> set_fs() is older than some kernel hackers!
>>
>> $ cd linux-0.11/
>> $ find . -type f -name '*.h' | xargs grep -e set_fs -w -n -A3
>> ./include/asm/segment.h:61:extern inline void set_fs(unsigned long val)
>> ./include/asm/segment.h-62-{
>> ./include/asm/segment.h-63- __asm__("mov %0,%%fs"::"a" ((unsigned short) val));
>> ./include/asm/segment.h-64-}
>
> What is this strange %fs register you are talking about.
> Figure 2-4 only has CS, DS, SS and ES.
>
Intel added registers FS and GS in the i386
Christophe
^ permalink raw reply
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