Re: [PATCH 07/15] powerpc/watchpoint: Get watchpoint count dynamically while disabling them

On 3/18/20 12:27 PM, Ravi Bangoria wrote: On 3/17/20 4:02 PM, Christophe Leroy wrote: Le 09/03/2020 à 09:57, Ravi Bangoria a écrit : Instead of disabling only one watchpooint, get num of available watchpoints dynamically and disable all of them. Signed-off-by: Ravi Bangoria ---  

Re: [PATCH v2] Documentation/locking/locktypes: minor copy editor fixes

d-by: Paul E. McKenney > --- > Documentation/locking/locktypes.rst | 16 > 1 file changed, 8 insertions(+), 8 deletions(-) > > --- linux-next-20200325.orig/Documentation/locking/locktypes.rst > +++ linux-next-20200325/Documentation/locking/locktypes.rst > @@ -8

Re: [PATCH V2 0/3] mm/debug: Add more arch page table helper tests

On 03/24/2020 10:52 AM, Anshuman Khandual wrote: > This series adds more arch page table helper tests. The new tests here are > either related to core memory functions and advanced arch pgtable helpers. > This also creates a documentation file enlisting all expected semantics as > suggested by

Re: [PATCH V2 1/3] mm/debug: Add tests validating arch page table helpers for core features

On 03/24/2020 06:59 PM, Zi Yan wrote: > On 24 Mar 2020, at 1:22, Anshuman Khandual wrote: > >> This adds new tests validating arch page table helpers for these following >> core memory features. These tests create and test specific mapping types at >> various page table levels. >> >> 1. SPECIAL

Re: [PATCH 1/2] dma-mapping: add a dma_ops_bypass flag to struct device

On 25/03/2020 19:37, Christoph Hellwig wrote: > On Wed, Mar 25, 2020 at 03:51:36PM +1100, Alexey Kardashevskiy wrote: This is for persistent memory which you can DMA to/from but yet it does not appear in the system as a normal memory and therefore requires special handling anyway

Re: [PATCH] mm/sparse: Fix kernel crash with pfn_section_valid check

On Wed, 25 Mar 2020 08:49:14 +0530 "Aneesh Kumar K.V" wrote: > Fixes the below crash (cc's added) > BUG: Kernel NULL pointer dereference on read at 0x > Faulting instruction address: 0xc0c3447c > Oops: Kernel access of bad area, sig: 11 [#1] > LE PAGE_SIZE=64K MMU=Hash SMP

Re: hardcoded SIGSEGV in __die() ?

Joakim Tjernlund writes: > On Mon, 2020-03-23 at 15:45 +0100, Christophe Leroy wrote: >> Le 23/03/2020 à 15:43, Christophe Leroy a écrit : >> > Le 23/03/2020 à 15:17, Joakim Tjernlund a écrit : >> > > In __die(), see below, there is this call to notify_send() with >> > > SIGSEGV hardcoded, this

Re: hardcoded SIGSEGV in __die() ?

On Wed, 2020-03-25 at 17:02 +, David Laight wrote: > CAUTION: This email originated from outside of the organization. Do > not click links or open attachments unless you recognize the sender > and know the content is safe. > > > From: Joakim Tjernlund > > Sent: 23 March 2020 15:45 > ... > >

RE: hardcoded SIGSEGV in __die() ?

From: Joakim Tjernlund > Sent: 23 March 2020 15:45 ... > > > I tried to follow that chain thinking it would end up sending a signal to > > > user space but I cannot > see > > > that happens. Seems to be related to debugging. > > > > > > In short, I cannot see any signal being delivered to user

[PATCH v2] Documentation/locking/locktypes: minor copy editor fixes

eixner Cc: Sebastian Siewior Cc: Joel Fernandes Cc: Ingo Molnar Cc: Peter Zijlstra --- Documentation/locking/locktypes.rst | 16 1 file changed, 8 insertions(+), 8 deletions(-) --- linux-next-20200325.orig/Documentation/locking/locktypes.rst +++ linux-next-20200325/Doc

Re: Documentation/locking/locktypes: Further clarifications and wordsmithing

On 2020-03-25 09:39:19 [-0700], Paul E. McKenney wrote: > > > --- a/Documentation/locking/locktypes.rst > > > +++ b/Documentation/locking/locktypes.rst > > … > > > +rw_semaphore > > > + > > > + > > > +rw_semaphore is a multiple readers and single writer lock mechanism. > > > + > > >

Re: Documentation/locking/locktypes: Further clarifications and wordsmithing

On Wed, Mar 25, 2020 at 05:02:12PM +0100, Sebastian Siewior wrote: > On 2020-03-25 13:27:49 [+0100], Thomas Gleixner wrote: > > The documentation of rw_semaphores is wrong as it claims that the non-owner > > reader release is not supported by RT. That's just history biased memory > > distortion. >

Re: Documentation/locking/locktypes: Further clarifications and wordsmithing

On 2020-03-25 13:27:49 [+0100], Thomas Gleixner wrote: > The documentation of rw_semaphores is wrong as it claims that the non-owner > reader release is not supported by RT. That's just history biased memory > distortion. > > Split the 'Owner semantics' section up and add separate sections for >

Re: [PATCH] powerpc/prom_init: Include the termination message in ibm, os-term RTAS call

Michael Ellerman writes: > Fabiano Rosas writes: > >> QEMU can now print the ibm,os-term message[1], so let's include it in >> the RTAS call. E.g.: >> >> qemu-system-ppc64: OS terminated: Switch to secure mode failed. >> >> 1- https://git.qemu.org/?p=qemu.git;a=commitdiff;h=a4c3791ae0 >> >>

Re: [PATCH] powerpc/prom_init: Include the termination message in ibm,os-term RTAS call

On Tue, Mar 24, 2020 at 05:12:11PM -0300, Fabiano Rosas wrote: > QEMU can now print the ibm,os-term message[1], so let's include it in > the RTAS call. E.g.: > > qemu-system-ppc64: OS terminated: Switch to secure mode failed. > > 1- https://git.qemu.org/?p=qemu.git;a=commitdiff;h=a4c3791ae0 >

Documentation/locking/locktypes: Further clarifications and wordsmithing

The documentation of rw_semaphores is wrong as it claims that the non-owner reader release is not supported by RT. That's just history biased memory distortion. Split the 'Owner semantics' section up and add separate sections for semaphore and rw_semaphore to reflect reality. Aside of that the

Re: [PATCH] powerpc/prom_init: Include the termination message in ibm,os-term RTAS call

On Wed, 25 Mar 2020 21:06:22 +1100 Michael Ellerman wrote: > Fabiano Rosas writes: > > > QEMU can now print the ibm,os-term message[1], so let's include it in > > the RTAS call. E.g.: > > > > qemu-system-ppc64: OS terminated: Switch to secure mode failed. > > > > 1-

Re: [PATCH v8 03/14] powerpc/vas: Define nx_fault_stamp in coprocessor_request_block

Haren Myneni writes: > On Mon, 2020-03-23 at 22:32 +1100, Michael Ellerman wrote: >> Nicholas Piggin writes: >> > Haren Myneni's on March 19, 2020 4:13 pm: >> >> >> >> Kernel sets fault address and status in CRB for NX page fault on user >> >> space address after processing page fault. User

Re: [PATCH] powerpc/boot: Delete unneeded .globl _zimage_start

Fangrui Song writes: > .globl sets the symbol binding to STB_GLOBAL while .weak sets the > binding to STB_WEAK. They should not be used together. It is accidetal > rather then intentional that GNU as let .weak override .globl while > clang integrated assembler let the last win. > Fixes:

[PATCH v2] powerpc/64: mark emergency stacks valid to unwind

Before: WARNING: CPU: 0 PID: 494 at arch/powerpc/kernel/irq.c:343 CPU: 0 PID: 494 Comm: a Tainted: GW NIP: c001ed2c LR: c0d13190 CTR: c003f910 REGS: c001fffd3870 TRAP: 0700 Tainted: GW MSR: 80021003 CR: 28000488 XER:

Re: [PATCH] cpufreq: powernv: Fix frame-size-overflow in powernv_cpufreq_work_fn

On Tuesday, March 24, 2020 7:34:56 AM CET Michael Ellerman wrote: > "Rafael J. Wysocki" writes: > > On Monday, March 16, 2020 2:57:43 PM CET Pratik Rajesh Sampat wrote: > >> The patch avoids allocating cpufreq_policy on stack hence fixing frame > >> size overflow in 'powernv_cpufreq_work_fn' > >>

[PATCH v2 12/12] powerpc/64s: system reset do not trace

Similarly to the previous patch, do not trace system reset. This code is used when there is a crash or hang, and tracing disturbs the system more and has been known to crash in the crash handling path. Signed-off-by: Nicholas Piggin --- arch/powerpc/kernel/traps.c | 5 + 1 file changed, 5

[PATCH v2 11/12] powerpc/64s: machine check do not trace real-mode handler

Rather than notrace annotations throughout a significant part of the machine check code across kernel/ pseries/ and powernv/ which can easily be broken and is infrequently tested, use paca->ftrace_enabled to blanket-disable tracing of the real-mode non-maskable handler. Signed-off-by: Nicholas

[PATCH v2 10/12] powerpc/64s: machine check interrupt update NMI accounting

machine_check_early is taken as an NMI, so nmi_enter is used there. machine_check_exception is no longer taken as an NMI (it's invoked via irq_work in the case a machine check hits in kernel mode), so remove the nmi_enter from that case. In NMI context, hash faults don't try to refill the hash

[PATCH v2 09/12] powerpc/pseries: machine check use rtas_call_unlocked with args on stack

With the previous patch, machine checks can use rtas_call_unlocked which avoids the rtas spinlock which would deadlock if a machine check hits while making an rtas call. This also avoids the complex rtas error logging which has more rtas calls and includes kmalloc (which can return memory beyond

[PATCH v2 08/12] powerpc/pseries: limit machine check stack to 4GB

This allows rtas_args to be put on the machine check stack, which avoids a lot of complications with re-entrancy deadlocks. Signed-off-by: Nicholas Piggin --- arch/powerpc/kernel/setup_64.c | 15 ++- 1 file changed, 14 insertions(+), 1 deletion(-) diff --git

[PATCH v2 07/12] powerpc/pseries/ras: fwnmi sreset should not interlock

PAPR does not specify that fwnmi sreset should be interlocked, and PowerVM (and therefore now QEMU) do not require it. These "ibm,nmi-interlock" calls are ignored by firmware, but there is a possibility that the sreset could have interrupted a machine check and release the machine check's

[PATCH v2 06/12] powerpc/pseries/ras: fwnmi avoid modifying r3 in error case

If there is some error with the fwnmi save area, r3 has already been modified which doesn't help with debugging. Only update r3 when to restore the saved value. Signed-off-by: Nicholas Piggin --- arch/powerpc/platforms/pseries/ras.c | 7 --- 1 file changed, 4 insertions(+), 3 deletions(-)

[PATCH v2 05/12] powerpc/pseries/ras: FWNMI_VALID off by one

This was discovered developing qemu fwnmi sreset support. This off-by-one bug means the last 16 bytes of the rtas area can not be used for a 16 byte save area. It's not a serious bug, and QEMU implementation has to retain a workaround for old kernels, but it's good to tighten it. Signed-off-by:

[PATCH v2 04/12] powerpc/pseries/ras: avoid calling rtas_token in NMI paths

In the interest of reducing code and possible failures in the machine check and system reset paths, grab the "ibm,nmi-interlock" token at init time. Signed-off-by: Nicholas Piggin --- arch/powerpc/include/asm/firmware.h| 1 + arch/powerpc/platforms/pseries/ras.c | 2 +-

[PATCH v2 03/12] powerpc/64s/exceptions: machine check reconcile irq state

pseries fwnmi machine check code pops the soft-irq checks in rtas_call (after the previous patch to remove rtas_token from this call path). Rather than play whack a mole with these and forever having fragile code, it seems better to have the early machine check handler perform the same kind of

[PATCH v2 02/12] powerpc/64s/exceptions: Change irq reconcile for NMIs from reusing _DAR to RESULT

A spare interrupt stack slot is needed to save irq state when reconciling NMIs (sreset and decrementer soft-nmi). _DAR is used for this, but we want to reconcile machine checks as well, which do use _DAR. Switch to using RESULT instead, as it's used by system calls. Signed-off-by: Nicholas Piggin

[PATCH v2 01/12] powerpc/64s/exceptions: Fix in_mce accounting in unrecoverable path

Signed-off-by: Nicholas Piggin --- arch/powerpc/kernel/exceptions-64s.S | 4 1 file changed, 4 insertions(+) diff --git a/arch/powerpc/kernel/exceptions-64s.S b/arch/powerpc/kernel/exceptions-64s.S index 6a936c9199d6..67cbcb2d0c7f 100644 --- a/arch/powerpc/kernel/exceptions-64s.S +++

[PATCH v2 00/12] powerpc/64: machine check and system reset fixes

There's a bunch of problems we hit bringing up fwnmi sreset and testing with mce injection on QEMU. Mostly pseries issues. This series of fixes applies on top of next-test, the machine check reconcile patch won't apply cleanly to previous kernels but it might want to be backported. We can do that

Re: [PATCH v4] powerpc: Replace setup_irq() by request_irq()

afzal mohammed writes: > Hi Michael Ellerman, > On Thu, Mar 12, 2020 at 12:12:55PM +0530, afzal mohammed wrote: >> request_irq() is preferred over setup_irq(). Invocations of setup_irq() >> occur after memory allocators are ready. >> >> Per tglx[1], setup_irq() existed in olden days when

Re: [PATCH] powerpc/prom_init: Include the termination message in ibm, os-term RTAS call

Fabiano Rosas writes: > QEMU can now print the ibm,os-term message[1], so let's include it in > the RTAS call. E.g.: > > qemu-system-ppc64: OS terminated: Switch to secure mode failed. > > 1- https://git.qemu.org/?p=qemu.git;a=commitdiff;h=a4c3791ae0 > > Signed-off-by: Fabiano Rosas > --- >

Re: [PATCH 1/4] hugetlbfs: add arch_hugetlb_valid_size

On 25.03.20 03:58, Longpeng (Mike, Cloud Infrastructure Service Product Dept.) wrote: [...] > Hi Mike, > > Inspired by Dave's opinion, it seems the x86-specific hugepages_supported > should > also need to use cpu_feature_enabled instead. > > Also, I wonder if the hugepages_supported is

[PATCH 1/2] Fix 2 "[v3, 25/32] powerpc/64: system call implement entry/exit logic in C"

This fixes 4 issues caught by TM selftests. First was a tm-syscall bug that hit due to tabort_syscall being called after interrupts were reconciled (in a subsequent patch), which led to interrupts being enabled before tabort_syscall was called. Rather than going through an un-reconciling

[PATCH 2/2] Fix 3 "[v3, 28/32] powerpc/64s: interrupt implement exit logic in C"

This fixes the interrupt-return part of the MSR_VSX restore bug caught by tm-unavailable selftest. Signed-off-by: Nicholas Piggin --- arch/powerpc/kernel/syscall_64.c | 24 +--- 1 file changed, 13 insertions(+), 11 deletions(-) diff --git a/arch/powerpc/kernel/syscall_64.c

Re: [PATCH] powerpc/boot: Delete unneeded .globl _zimage_start

On Wed, Mar 25, 2020 at 05:22:31AM +, Joel Stanley wrote: > On Wed, 25 Mar 2020 at 05:19, Fangrui Song wrote: > > > > .globl sets the symbol binding to STB_GLOBAL while .weak sets the > > binding to STB_WEAK. They should not be used together. It is accidetal > > rather then intentional that

Re: [patch V3 03/20] usb: gadget: Use completion interface instead of open coding it

Thomas Gleixner writes: > From: Thomas Gleixner > > ep_io() uses a completion on stack and open codes the waiting with: > > wait_event_interruptible (done.wait, done.done); > and > wait_event (done.wait, done.done); > > This waits in non-exclusive mode for complete(), but there is no reason

Re: [PATCH 1/2] dma-mapping: add a dma_ops_bypass flag to struct device

On Wed, Mar 25, 2020 at 03:51:36PM +1100, Alexey Kardashevskiy wrote: > >> This is for persistent memory which you can DMA to/from but yet it does > >> not appear in the system as a normal memory and therefore requires > >> special handling anyway (O_DIRECT or DAX, I do not know the exact > >>

Re: [PATCH] mm/sparse: Fix kernel crash with pfn_section_valid check

On 03/25/20 at 01:42pm, Aneesh Kumar K.V wrote: > On 3/25/20 1:07 PM, Baoquan He wrote: > > On 03/25/20 at 03:06pm, Baoquan He wrote: > > > On 03/25/20 at 08:49am, Aneesh Kumar K.V wrote: > > > > > > mm/sparse.c | 2 ++ > > > > 1 file changed, 2 insertions(+) > > > > > > > > diff --git

Re: [PATCH] mm/sparse: Fix kernel crash with pfn_section_valid check

On 3/25/20 1:07 PM, Baoquan He wrote: On 03/25/20 at 03:06pm, Baoquan He wrote: On 03/25/20 at 08:49am, Aneesh Kumar K.V wrote: mm/sparse.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/mm/sparse.c b/mm/sparse.c index aadb7298dcef..3012d1f3771a 100644 --- a/mm/sparse.c +++

Re: [PATCH] mm/sparse: Fix kernel crash with pfn_section_valid check

On 03/25/20 at 03:06pm, Baoquan He wrote: > On 03/25/20 at 08:49am, Aneesh Kumar K.V wrote: > > mm/sparse.c | 2 ++ > > 1 file changed, 2 insertions(+) > > > > diff --git a/mm/sparse.c b/mm/sparse.c > > index aadb7298dcef..3012d1f3771a 100644 > > --- a/mm/sparse.c > > +++ b/mm/sparse.c > > @@

Re: [PATCH] mm/sparse: Fix kernel crash with pfn_section_valid check

On 03/25/20 at 08:49am, Aneesh Kumar K.V wrote: > Fixes the below crash > > BUG: Kernel NULL pointer dereference on read at 0x > Faulting instruction address: 0xc0c3447c > Oops: Kernel access of bad area, sig: 11 [#1] > LE PAGE_SIZE=64K MMU=Hash SMP NR_CPUS=2048 NUMA pSeries >

Re: [PATCH] powerpc/boot: Delete unneeded .globl _zimage_start

On Tue, Mar 24, 2020 at 10:18:20PM -0700, Fangrui Song wrote: > .globl sets the symbol binding to STB_GLOBAL while .weak sets the > binding to STB_WEAK. They should not be used together. It is accidetal > rather then intentional that GNU as let .weak override .globl while > clang integrated

Re: Argh, can't find dcache properties !

Qian Cai writes: >> On Mar 24, 2020, at 4:06 PM, Chris Packham >> wrote: >> On Tue, 2020-03-24 at 15:47 +1100, Michael Ellerman wrote: >>> Chris Packham writes: Hi All, Just booting up v5.5.11 on a Freescale T2080RDB and I'm seeing the following mesage.