* Re: [PATCH 11/11 v2.2] ftrace: Add recording of functions that caused recursion
From: Steven Rostedt @ 2020-11-03 16:14 UTC (permalink / raw)
To: Petr Mladek
Cc: Anton Vorontsov, linux-doc, Peter Zijlstra,
Sebastian Andrzej Siewior, Kamalesh Babulal, James E.J. Bottomley,
Guo Ren, H. Peter Anvin, live-patching, Miroslav Benes,
Ingo Molnar, linux-s390, Joe Lawrence, Jonathan Corbet,
Mauro Carvalho Chehab, Helge Deller, x86, linux-csky,
Christian Borntraeger, Kees Cook, Vasily Gorbik, Heiko Carstens,
Jiri Kosina, Borislav Petkov, Josh Poimboeuf, Thomas Gleixner,
Tony Luck, linux-parisc, linux-kernel, Masami Hiramatsu,
Colin Cross, Paul Mackerras, Andrew Morton, linuxppc-dev
In-Reply-To: <20201103141043.GO20201@alley>
On Tue, 3 Nov 2020 15:10:43 +0100
Petr Mladek <pmladek@suse.com> wrote:
> BTW: What is actually the purpose of paranoid_test, please?
>
> It prevents nested ftrace_record_recursion() calls on the same CPU
> (recursion, nesting from IRQ, NMI context).
>
> Parallel calls from different CPUs are still possible:
>
> CPU0 CPU1
> if (!atomic_read(¶noid_test)) if (!atomic_read(¶noid_test))
> // passes // passes
> atomic_inc(¶noid_test); atomic_inc(¶noid_test);
>
>
> I do not see how a nested call could cause crash while a parallel
> one would be OK.
>
Yeah, I should make that per cpu, but was lazy. ;-)
It was added at the end.
I'll update that to a per cpu, and local inc operations.
-- Steve
^ permalink raw reply
* Re: [PATCH v3 2/4] PM: hibernate: make direct map manipulations more explicit
From: Mike Rapoport @ 2020-11-03 15:56 UTC (permalink / raw)
To: Kirill A. Shutemov
Cc: Rafael J . Wysocki, David Hildenbrand, Peter Zijlstra,
Dave Hansen, linux-mm, Paul Mackerras, Pavel Machek,
H. Peter Anvin, sparclinux, Christoph Lameter, Will Deacon,
linux-riscv, linux-s390, x86, Mike Rapoport,
Christian Borntraeger, Ingo Molnar, Catalin Marinas, Len Brown,
Albert Ou, Vasily Gorbik, linux-pm, Heiko Carstens,
David Rientjes, Borislav Petkov, Andy Lutomirski, Paul Walmsley,
Thomas Gleixner, Joonsoo Kim, linux-arm-kernel, Rafael J. Wysocki,
linux-kernel, Pekka Enberg, Palmer Dabbelt, Andrew Morton,
Edgecombe, Rick P, linuxppc-dev, David S. Miller
In-Reply-To: <20201103143916.otz2o4h2dlmewn3h@box>
On Tue, Nov 03, 2020 at 05:39:16PM +0300, Kirill A. Shutemov wrote:
> On Tue, Nov 03, 2020 at 02:13:50PM +0200, Mike Rapoport wrote:
> > > > +
> > > > + if (WARN_ON(ret))
> > >
> > > _ONCE?
> >
> > I've changed it to pr_warn() after David said people enable panic on
> > warn in production kernels.
>
> pr_warn_once()? :P
Sure :)
--
Sincerely yours,
Mike.
^ permalink raw reply
* [PATCH 25/25] soc: fsl: qbman: qman: Remove unused variable 'dequeue_wq'
From: Lee Jones @ 2020-11-03 15:28 UTC (permalink / raw)
To: lee.jones
Cc: linuxppc-dev, YueHaibing, linux-kernel, linux-arm-kernel, Li Yang
In-Reply-To: <20201103152838.1290217-1-lee.jones@linaro.org>
Fixes the following W=1 kernel build warning(s):
drivers/soc/fsl/qbman/qman.c: In function ‘qman_shutdown_fq’:
drivers/soc/fsl/qbman/qman.c:2700:8: warning: variable ‘dequeue_wq’ set but not used [-Wunused-but-set-variable]
Cc: Li Yang <leoyang.li@nxp.com>
Cc: YueHaibing <yuehaibing@huawei.com>
Cc: linuxppc-dev@lists.ozlabs.org
Signed-off-by: Lee Jones <lee.jones@linaro.org>
---
drivers/soc/fsl/qbman/qman.c | 8 ++------
1 file changed, 2 insertions(+), 6 deletions(-)
diff --git a/drivers/soc/fsl/qbman/qman.c b/drivers/soc/fsl/qbman/qman.c
index 9888a70618730..62b182c3a8b04 100644
--- a/drivers/soc/fsl/qbman/qman.c
+++ b/drivers/soc/fsl/qbman/qman.c
@@ -2622,7 +2622,7 @@ int qman_shutdown_fq(u32 fqid)
union qm_mc_command *mcc;
union qm_mc_result *mcr;
int orl_empty, drain = 0, ret = 0;
- u32 channel, wq, res;
+ u32 channel, res;
u8 state;
p = get_affine_portal();
@@ -2655,7 +2655,7 @@ int qman_shutdown_fq(u32 fqid)
DPAA_ASSERT((mcr->verb & QM_MCR_VERB_MASK) == QM_MCR_VERB_QUERYFQ);
/* Need to store these since the MCR gets reused */
channel = qm_fqd_get_chan(&mcr->queryfq.fqd);
- wq = qm_fqd_get_wq(&mcr->queryfq.fqd);
+ qm_fqd_get_wq(&mcr->queryfq.fqd);
if (channel < qm_channel_pool1) {
channel_portal = get_portal_for_channel(channel);
@@ -2697,7 +2697,6 @@ int qman_shutdown_fq(u32 fqid)
* to dequeue from the channel the FQ is scheduled on
*/
int found_fqrn = 0;
- u16 dequeue_wq = 0;
/* Flag that we need to drain FQ */
drain = 1;
@@ -2705,11 +2704,8 @@ int qman_shutdown_fq(u32 fqid)
if (channel >= qm_channel_pool1 &&
channel < qm_channel_pool1 + 15) {
/* Pool channel, enable the bit in the portal */
- dequeue_wq = (channel -
- qm_channel_pool1 + 1)<<4 | wq;
} else if (channel < qm_channel_pool1) {
/* Dedicated channel */
- dequeue_wq = wq;
} else {
dev_err(dev, "Can't recover FQ 0x%x, ch: 0x%x",
fqid, channel);
--
2.25.1
^ permalink raw reply related
* [PATCH 11/25] soc: fsl: qe: qe_common: Fix misnamed function attribute 'addr'
From: Lee Jones @ 2020-11-03 15:28 UTC (permalink / raw)
To: lee.jones
Cc: Software, Inc, linux-kernel, Li Yang, act, Dan Malek,
Vitaly Bordug, Scott Wood, linuxppc-dev, linux-arm-kernel,
Qiang Zhao
In-Reply-To: <20201103152838.1290217-1-lee.jones@linaro.org>
Fixes the following W=1 kernel build warning(s):
drivers/soc/fsl/qe/qe_common.c:237: warning: Function parameter or member 'addr' not described in 'cpm_muram_dma'
drivers/soc/fsl/qe/qe_common.c:237: warning: Excess function parameter 'offset' description in 'cpm_muram_dma'
Cc: Qiang Zhao <qiang.zhao@nxp.com>
Cc: Li Yang <leoyang.li@nxp.com>
Cc: Scott Wood <scottwood@freescale.com>
Cc: act <dmalek@jlc.net>
Cc: Dan Malek <dan@embeddedalley.com>
Cc: "Software, Inc" <source@mvista.com>
Cc: Vitaly Bordug <vbordug@ru.mvista.com>
Cc: linuxppc-dev@lists.ozlabs.org
Signed-off-by: Lee Jones <lee.jones@linaro.org>
---
drivers/soc/fsl/qe/qe_common.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/soc/fsl/qe/qe_common.c b/drivers/soc/fsl/qe/qe_common.c
index 75075591f6308..497a7e0fd0272 100644
--- a/drivers/soc/fsl/qe/qe_common.c
+++ b/drivers/soc/fsl/qe/qe_common.c
@@ -231,7 +231,7 @@ EXPORT_SYMBOL(cpm_muram_offset);
/**
* cpm_muram_dma - turn a muram virtual address into a DMA address
- * @offset: virtual address from cpm_muram_addr() to convert
+ * @addr: virtual address from cpm_muram_addr() to convert
*/
dma_addr_t cpm_muram_dma(void __iomem *addr)
{
--
2.25.1
^ permalink raw reply related
* [PATCH 04/25] soc: fsl: dpio: qbman-portal: Fix a bunch of kernel-doc misdemeanours
From: Lee Jones @ 2020-11-03 15:28 UTC (permalink / raw)
To: lee.jones
Cc: Roy Pledge, linuxppc-dev, linux-kernel, linux-arm-kernel, Li Yang
In-Reply-To: <20201103152838.1290217-1-lee.jones@linaro.org>
Fixes the following W=1 kernel build warning(s):
drivers/soc/fsl/dpio/qbman-portal.c:430: warning: Function parameter or member 'inhibit' not described in 'qbman_swp_interrupt_set_inhibit'
drivers/soc/fsl/dpio/qbman-portal.c:430: warning: Excess function parameter 'mask' description in 'qbman_swp_interrupt_set_inhibit'
drivers/soc/fsl/dpio/qbman-portal.c:518: warning: Function parameter or member 'd' not described in 'qbman_eq_desc_clear'
drivers/soc/fsl/dpio/qbman-portal.c:529: warning: Function parameter or member 'respond_success' not described in 'qbman_eq_desc_set_no_orp'
drivers/soc/fsl/dpio/qbman-portal.c:529: warning: Excess function parameter 'response_success' description in 'qbman_eq_desc_set_no_orp'
drivers/soc/fsl/dpio/qbman-portal.c:941: warning: Function parameter or member 's' not described in 'qbman_swp_push_get'
drivers/soc/fsl/dpio/qbman-portal.c:941: warning: Excess function parameter 'p' description in 'qbman_swp_push_get'
drivers/soc/fsl/dpio/qbman-portal.c:955: warning: Function parameter or member 's' not described in 'qbman_swp_push_set'
drivers/soc/fsl/dpio/qbman-portal.c:955: warning: Excess function parameter 'p' description in 'qbman_swp_push_set'
drivers/soc/fsl/dpio/qbman-portal.c:1052: warning: Function parameter or member 'd' not described in 'qbman_pull_desc_set_fq'
drivers/soc/fsl/dpio/qbman-portal.c:1065: warning: Function parameter or member 'd' not described in 'qbman_pull_desc_set_wq'
drivers/soc/fsl/dpio/qbman-portal.c:1079: warning: Function parameter or member 'd' not described in 'qbman_pull_desc_set_channel'
drivers/soc/fsl/dpio/qbman-portal.c:1403: warning: Function parameter or member 'd' not described in 'qbman_release_desc_clear'
drivers/soc/fsl/dpio/qbman-portal.c:1412: warning: Function parameter or member 'd' not described in 'qbman_release_desc_set_bpid'
drivers/soc/fsl/dpio/qbman-portal.c:1412: warning: Function parameter or member 'bpid' not described in 'qbman_release_desc_set_bpid'
drivers/soc/fsl/dpio/qbman-portal.c:1421: warning: Function parameter or member 'd' not described in 'qbman_release_desc_set_rcdi'
drivers/soc/fsl/dpio/qbman-portal.c:1421: warning: Function parameter or member 'enable' not described in 'qbman_release_desc_set_rcdi'
Cc: Roy Pledge <Roy.Pledge@nxp.com>
Cc: Li Yang <leoyang.li@nxp.com>
Cc: linuxppc-dev@lists.ozlabs.org
Signed-off-by: Lee Jones <lee.jones@linaro.org>
---
drivers/soc/fsl/dpio/qbman-portal.c | 18 +++++++++++++-----
1 file changed, 13 insertions(+), 5 deletions(-)
diff --git a/drivers/soc/fsl/dpio/qbman-portal.c b/drivers/soc/fsl/dpio/qbman-portal.c
index 659b4a570d5b5..f13da4d7d1c52 100644
--- a/drivers/soc/fsl/dpio/qbman-portal.c
+++ b/drivers/soc/fsl/dpio/qbman-portal.c
@@ -424,7 +424,7 @@ int qbman_swp_interrupt_get_inhibit(struct qbman_swp *p)
/**
* qbman_swp_interrupt_set_inhibit() - write interrupt mask register
* @p: the given software portal object
- * @mask: The mask to set in SWP_IIR register
+ * @inhibit: whether to inhibit the IRQs
*/
void qbman_swp_interrupt_set_inhibit(struct qbman_swp *p, int inhibit)
{
@@ -510,7 +510,7 @@ enum qb_enqueue_commands {
#define QB_ENQUEUE_CMD_TARGET_TYPE_SHIFT 4
#define QB_ENQUEUE_CMD_DCA_EN_SHIFT 7
-/**
+/*
* qbman_eq_desc_clear() - Clear the contents of a descriptor to
* default/starting state.
*/
@@ -522,7 +522,7 @@ void qbman_eq_desc_clear(struct qbman_eq_desc *d)
/**
* qbman_eq_desc_set_no_orp() - Set enqueue descriptor without orp
* @d: the enqueue descriptor.
- * @response_success: 1 = enqueue with response always; 0 = enqueue with
+ * @respond_success: 1 = enqueue with response always; 0 = enqueue with
* rejections returned on a FQ.
*/
void qbman_eq_desc_set_no_orp(struct qbman_eq_desc *d, int respond_success)
@@ -932,7 +932,7 @@ int qbman_swp_enqueue_multiple_desc_mem_back(struct qbman_swp *s,
/**
* qbman_swp_push_get() - Get the push dequeue setup
- * @p: the software portal object
+ * @s: the software portal object
* @channel_idx: the channel index to query
* @enabled: returned boolean to show whether the push dequeue is enabled
* for the given channel
@@ -947,7 +947,7 @@ void qbman_swp_push_get(struct qbman_swp *s, u8 channel_idx, int *enabled)
/**
* qbman_swp_push_set() - Enable or disable push dequeue
- * @p: the software portal object
+ * @s: the software portal object
* @channel_idx: the channel index (0 to 15)
* @enable: enable or disable push dequeue
*/
@@ -1046,6 +1046,7 @@ void qbman_pull_desc_set_numframes(struct qbman_pull_desc *d, u8 numframes)
/**
* qbman_pull_desc_set_fq() - Set fqid from which the dequeue command dequeues
+ * @d: the pull dequeue descriptor to be set
* @fqid: the frame queue index of the given FQ
*/
void qbman_pull_desc_set_fq(struct qbman_pull_desc *d, u32 fqid)
@@ -1057,6 +1058,7 @@ void qbman_pull_desc_set_fq(struct qbman_pull_desc *d, u32 fqid)
/**
* qbman_pull_desc_set_wq() - Set wqid from which the dequeue command dequeues
+ * @d: the pull dequeue descriptor to be set
* @wqid: composed of channel id and wqid within the channel
* @dct: the dequeue command type
*/
@@ -1071,6 +1073,7 @@ void qbman_pull_desc_set_wq(struct qbman_pull_desc *d, u32 wqid,
/**
* qbman_pull_desc_set_channel() - Set channelid from which the dequeue command
* dequeues
+ * @d: the pull dequeue descriptor to be set
* @chid: the channel id to be dequeued
* @dct: the dequeue command type
*/
@@ -1398,6 +1401,7 @@ int qbman_result_has_new_result(struct qbman_swp *s, const struct dpaa2_dq *dq)
/**
* qbman_release_desc_clear() - Clear the contents of a descriptor to
* default/starting state.
+ * @d: the pull dequeue descriptor to be cleared
*/
void qbman_release_desc_clear(struct qbman_release_desc *d)
{
@@ -1407,6 +1411,8 @@ void qbman_release_desc_clear(struct qbman_release_desc *d)
/**
* qbman_release_desc_set_bpid() - Set the ID of the buffer pool to release to
+ * @d: the pull dequeue descriptor to be set
+ * @bpid: the bpid value to be set
*/
void qbman_release_desc_set_bpid(struct qbman_release_desc *d, u16 bpid)
{
@@ -1416,6 +1422,8 @@ void qbman_release_desc_set_bpid(struct qbman_release_desc *d, u16 bpid)
/**
* qbman_release_desc_set_rcdi() - Determines whether or not the portal's RCDI
* interrupt source should be asserted after the release command is completed.
+ * @d: the pull dequeue descriptor to be set
+ * @enable: enable (1) or disable (0) value
*/
void qbman_release_desc_set_rcdi(struct qbman_release_desc *d, int enable)
{
--
2.25.1
^ permalink raw reply related
* [PATCH 00/25] Rid W=1 warnings in SoC
From: Lee Jones @ 2020-11-03 15:28 UTC (permalink / raw)
To: lee.jones
Cc: Heiko Stuebner, Roy Pledge, Liam Girdwood, Scott Wood,
Thierry Reding, Li Yang, Qiang Zhao, linux-samsung-soc,
Rafael J. Wysocki, YueHaibing, Sandeep Nair, Krzysztof Kozlowski,
Jonathan Hunter, linux-rockchip, act, Andy Gross,
bcm-kernel-feedback-list, Cyril Chemparathy, linux-arm-msm,
Florian Fainelli, Santosh Shilimkar, linux-tegra, Bjorn Andersson,
linux-arm-kernel, Software, Inc, Dave Gerlach, Doug Anderson,
linux-kernel, Ben Dooks, Mark Brown, Dan Malek, Vitaly Bordug,
linuxppc-dev
This set is part of a larger effort attempting to clean-up W=1
kernel builds, which are currently overwhelmingly riddled with
niggly little warnings.
Lee Jones (25):
soc: bcm: brcmstb: pm: pm-arm: Provide prototype for
brcmstb_pm_s3_finish()
soc: qcom: qcom_aoss: Remove set but unused variable 'tlen'
soc: qcom: qcom_aoss: Add missing description for 'cooling_devs'
soc: fsl: dpio: qbman-portal: Fix a bunch of kernel-doc misdemeanours
soc: rockchip: io-domain: Remove incorrect and incomplete comment
header
soc: ti: knav_qmss_queue: Remove set but unchecked variable 'ret'
soc: ti: knav_qmss_queue: Fix a whole host of function documentation
issues
soc: ti: knav_dma: Fix a kernel function doc formatting issue
soc: ti: pm33xx: Remove set but unused variable 'ret'
soc: ti: wkup_m3_ipc: Document 'm3_ipc' parameter throughout
soc: fsl: qe: qe_common: Fix misnamed function attribute 'addr'
soc: qcom: qcom-geni-se: Fix misnamed function parameter 'rx_rfr'
soc: tegra: fuse: speedo-tegra124: Remove some set but unused
variables
soc: samsung: s3c-pm-check: Fix incorrectly named variable 'val'
soc: qcom: rpmh: Fix possible doc-rot in rpmh_write()'s header
soc: qcom: smem: Fix formatting and missing documentation issues
soc: qcom: smsm: Fix some kernel-doc formatting and naming problems
soc: qcom: wcnss_ctrl: Demote non-conformant struct header and fix
function headers
soc: qcom: smp2p: Remove unused struct attribute provide another
soc: qcom: llcc-qcom: Fix expected kernel-doc formatting
soc: qcom: rpmhpd: Provide some missing struct member descriptions
soc: qcom: kryo-l2-accessors: Fix misnaming of 'val'
soc: ti: k3-ringacc: Provide documentation for 'k3_ring's 'state'
soc: tegra: fuse: speedo-tegra210: Remove a group of set but unused
variables
soc: fsl: qbman: qman: Remove unused variable 'dequeue_wq'
drivers/soc/bcm/brcmstb/pm/pm-arm.c | 2 +
drivers/soc/fsl/dpio/qbman-portal.c | 18 +++++--
drivers/soc/fsl/qbman/qman.c | 8 +--
drivers/soc/fsl/qe/qe_common.c | 2 +-
drivers/soc/qcom/kryo-l2-accessors.c | 2 +-
drivers/soc/qcom/llcc-qcom.c | 2 +-
drivers/soc/qcom/qcom-geni-se.c | 5 +-
drivers/soc/qcom/qcom_aoss.c | 4 +-
drivers/soc/qcom/rpmh.c | 2 +-
drivers/soc/qcom/rpmhpd.c | 3 ++
drivers/soc/qcom/smem.c | 3 +-
drivers/soc/qcom/smp2p.c | 3 +-
drivers/soc/qcom/smsm.c | 4 +-
drivers/soc/qcom/wcnss_ctrl.c | 8 +--
drivers/soc/rockchip/io-domain.c | 3 --
drivers/soc/samsung/s3c-pm-check.c | 2 +-
drivers/soc/tegra/fuse/speedo-tegra124.c | 7 ++-
drivers/soc/tegra/fuse/speedo-tegra210.c | 8 +--
drivers/soc/ti/k3-ringacc.c | 1 +
drivers/soc/ti/knav_dma.c | 2 +-
drivers/soc/ti/knav_qmss_queue.c | 62 ++++++++++++------------
drivers/soc/ti/pm33xx.c | 4 +-
drivers/soc/ti/wkup_m3_ipc.c | 8 ++-
23 files changed, 86 insertions(+), 77 deletions(-)
Cc: act <dmalek@jlc.net>
Cc: Andy Gross <agross@kernel.org>
Cc: bcm-kernel-feedback-list@broadcom.com
Cc: Ben Dooks <ben@simtec.co.uk>
Cc: Bjorn Andersson <bjorn.andersson@linaro.org>
Cc: Cyril Chemparathy <cyril@ti.com>
Cc: Dan Malek <dan@embeddedalley.com>
Cc: Dave Gerlach <d-gerlach@ti.com>
Cc: Doug Anderson <dianders@chromium.org>
Cc: Florian Fainelli <f.fainelli@gmail.com>
Cc: Heiko Stuebner <heiko@sntech.de>
Cc: Jonathan Hunter <jonathanh@nvidia.com>
Cc: Krzysztof Kozlowski <krzk@kernel.org>
Cc: Liam Girdwood <lgirdwood@gmail.com>
Cc: linux-arm-msm@vger.kernel.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: linux-rockchip@lists.infradead.org
Cc: linux-samsung-soc@vger.kernel.org
Cc: linux-tegra@vger.kernel.org
Cc: Li Yang <leoyang.li@nxp.com>
Cc: Mark Brown <broonie@kernel.org>
Cc: Qiang Zhao <qiang.zhao@nxp.com>
Cc: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>
Cc: Roy Pledge <Roy.Pledge@nxp.com>
Cc: Sandeep Nair <sandeep_n@ti.com>
Cc: Santosh Shilimkar <ssantosh@kernel.org>
Cc: Scott Wood <scottwood@freescale.com>
Cc: "Software, Inc" <source@mvista.com>
Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: Vitaly Bordug <vbordug@ru.mvista.com>
Cc: YueHaibing <yuehaibing@huawei.com>
--
2.25.1
^ permalink raw reply
* Re: [PATCH 30/33] docs: ABI: cleanup several ABI documents
From: Bjorn Andersson @ 2020-11-03 15:24 UTC (permalink / raw)
To: Mauro Carvalho Chehab
Cc: linux-stm32, Linux Doc Mailing List, linux-iio, netdev, coresight,
linux-pm, linux-remoteproc, linux-kernel, dri-devel,
linux-f2fs-devel, linux-acpi, linux-gpio, linux-i3c, linuxppc-dev,
linux-fpga, linux-arm-kernel, linux-media
In-Reply-To: <95ef2cf3a58f4e50f17d9e58e0d9440ad14d0427.1603893146.git.mchehab+huawei@kernel.org>
On Wed 28 Oct 09:23 CDT 2020, Mauro Carvalho Chehab wrote:
[..]
> .../ABI/testing/sysfs-class-remoteproc | 14 +-
for this:
Acked-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Thanks,
Bjorn
^ permalink raw reply
* Re: [PATCH] powerpc: Don't use asm goto for put_user() with GCC 4.9
From: Christophe Leroy @ 2020-11-03 14:43 UTC (permalink / raw)
To: Michael Ellerman, linuxppc-dev; +Cc: schwab
In-Reply-To: <20201103132915.529337-1-mpe@ellerman.id.au>
Le 03/11/2020 à 14:29, Michael Ellerman a écrit :
> Andreas reported that commit ee0a49a6870e ("powerpc/uaccess: Switch
> __put_user_size_allowed() to __put_user_asm_goto()") broke
> CLONE_CHILD_SETTID.
>
> Further inspection showed that the put_user() in schedule_tail() was
> missing entirely, the store not emitted by the compiler.
>
>
> Notice there are no stores other than to the stack. There should be a
> stw in there for the store to current->set_child_tid.
>
> This is only seen with GCC 4.9 era compilers (tested with 4.9.3 and
> 4.9.4), and only when CONFIG_PPC_KUAP is disabled.
>
> When CONFIG_PPC_KUAP=y, the memory clobber that's part of the isync()
> and mtspr() inlined via allow_user_access() seems to be enough to
> avoid the bug.
>
> For now though let's just not use asm goto with GCC 4.9, to avoid this
> bug and any other issues we haven't noticed yet. Possibly in future we
> can find a smaller workaround.
Is that https://gcc.gnu.org/bugzilla/show_bug.cgi?id=58670 ?
Should we use asm_volatile_goto() defined in include/linux/compiler-gcc.h ?
Christophe
>
> This is basically a revert of commit ee0a49a6870e ("powerpc/uaccess:
> Switch __put_user_size_allowed() to __put_user_asm_goto()") and commit
> 7fdf966bed15 ("powerpc/uaccess: Remove __put_user_asm() and
> __put_user_asm2()"), but only for GCC 4.9.
>
> With this applied the code generation looks more like it will work:
>
>
> Fixes: ee0a49a6870e ("powerpc/uaccess: Switch __put_user_size_allowed() to __put_user_asm_goto()")
> Reported-by: Andreas Schwab <schwab@linux-m68k.org>
> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
> ---
> arch/powerpc/include/asm/uaccess.h | 48 ++++++++++++++++++++++++++++++
> 1 file changed, 48 insertions(+)
>
> diff --git a/arch/powerpc/include/asm/uaccess.h b/arch/powerpc/include/asm/uaccess.h
> index ef5bbb705c08..526a6658946b 100644
> --- a/arch/powerpc/include/asm/uaccess.h
> +++ b/arch/powerpc/include/asm/uaccess.h
> @@ -110,6 +110,52 @@ static inline bool __access_ok(unsigned long addr, unsigned long size)
>
> extern long __put_user_bad(void);
>
> +#if defined(GCC_VERSION) && GCC_VERSION < 50000
> +#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 { \
> + 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(); \
> + } \
> +} while (0)
> +
> +#else
> +
> #define __put_user_size_allowed(x, ptr, size, retval) \
> do { \
> __label__ __pu_failed; \
> @@ -122,6 +168,8 @@ __pu_failed: \
> retval = -EFAULT; \
> } while (0)
>
> +#endif /* GCC_VERSION */
> +
> #define __put_user_size(x, ptr, size, retval) \
> do { \
> allow_write_to_user(ptr, size); \
>
^ permalink raw reply
* Re: [PATCH v3 2/4] PM: hibernate: make direct map manipulations more explicit
From: Kirill A. Shutemov @ 2020-11-03 14:39 UTC (permalink / raw)
To: Mike Rapoport
Cc: Rafael J . Wysocki, David Hildenbrand, Peter Zijlstra,
Dave Hansen, linux-mm, Paul Mackerras, Pavel Machek,
H. Peter Anvin, sparclinux, Christoph Lameter, Will Deacon,
linux-riscv, linux-s390, x86, Mike Rapoport,
Christian Borntraeger, Ingo Molnar, Catalin Marinas, Len Brown,
Albert Ou, Vasily Gorbik, linux-pm, Heiko Carstens,
David Rientjes, Borislav Petkov, Andy Lutomirski, Paul Walmsley,
Thomas Gleixner, Joonsoo Kim, linux-arm-kernel, Rafael J. Wysocki,
linux-kernel, Pekka Enberg, Palmer Dabbelt, Andrew Morton,
Edgecombe, Rick P, linuxppc-dev, David S. Miller
In-Reply-To: <20201103121350.GI4879@kernel.org>
On Tue, Nov 03, 2020 at 02:13:50PM +0200, Mike Rapoport wrote:
> On Tue, Nov 03, 2020 at 02:08:16PM +0300, Kirill A. Shutemov wrote:
> > On Sun, Nov 01, 2020 at 07:08:13PM +0200, Mike Rapoport wrote:
> > > diff --git a/kernel/power/snapshot.c b/kernel/power/snapshot.c
> > > index 46b1804c1ddf..054c8cce4236 100644
> > > --- a/kernel/power/snapshot.c
> > > +++ b/kernel/power/snapshot.c
> > > @@ -76,6 +76,32 @@ static inline void hibernate_restore_protect_page(void *page_address) {}
> > > static inline void hibernate_restore_unprotect_page(void *page_address) {}
> > > #endif /* CONFIG_STRICT_KERNEL_RWX && CONFIG_ARCH_HAS_SET_MEMORY */
> > >
> > > +static inline void hibernate_map_page(struct page *page, int enable)
> > > +{
> > > + if (IS_ENABLED(CONFIG_ARCH_HAS_SET_DIRECT_MAP)) {
> > > + unsigned long addr = (unsigned long)page_address(page);
> > > + int ret;
> > > +
> > > + /*
> > > + * This should not fail because remapping a page here means
> > > + * that we only update protection bits in an existing PTE.
> > > + * It is still worth to have WARN_ON() here if something
> > > + * changes and this will no longer be the case.
> > > + */
> > > + if (enable)
> > > + ret = set_direct_map_default_noflush(page);
> > > + else
> > > + ret = set_direct_map_invalid_noflush(page);
> > > +
> > > + if (WARN_ON(ret))
> >
> > _ONCE?
>
> I've changed it to pr_warn() after David said people enable panic on
> warn in production kernels.
pr_warn_once()? :P
--
Kirill A. Shutemov
^ permalink raw reply
* Re: [PATCH 11/11 v2.2] ftrace: Add recording of functions that caused recursion
From: Petr Mladek @ 2020-11-03 14:10 UTC (permalink / raw)
To: Steven Rostedt
Cc: Anton Vorontsov, linux-doc, Peter Zijlstra,
Sebastian Andrzej Siewior, Kamalesh Babulal, James E.J. Bottomley,
Guo Ren, H. Peter Anvin, live-patching, Miroslav Benes,
Ingo Molnar, linux-s390, Joe Lawrence, Jonathan Corbet,
Mauro Carvalho Chehab, Helge Deller, x86, linux-csky,
Christian Borntraeger, Kees Cook, Vasily Gorbik, Heiko Carstens,
Jiri Kosina, Borislav Petkov, Josh Poimboeuf, Thomas Gleixner,
Tony Luck, linux-parisc, linux-kernel, Masami Hiramatsu,
Colin Cross, Paul Mackerras, Andrew Morton, linuxppc-dev
In-Reply-To: <20201102142254.7e148f8a@gandalf.local.home>
On Mon 2020-11-02 14:23:14, Steven Rostedt wrote:
> From c532ff6b048dd4a12943b05c7b8ce30666c587c8 Mon Sep 17 00:00:00 2001
> From: "Steven Rostedt (VMware)" <rostedt@goodmis.org>
> Date: Thu, 29 Oct 2020 15:27:06 -0400
> Subject: [PATCH] ftrace: Add recording of functions that caused recursion
>
> This adds CONFIG_FTRACE_RECORD_RECURSION that will record to a file
> "recursed_functions" all the functions that caused recursion while a
> callback to the function tracer was running.
>
> diff --git a/include/linux/trace_recursion.h b/include/linux/trace_recursion.h
> index ac3d73484cb2..1cba5fe8777a 100644
> --- a/include/linux/trace_recursion.h
> +++ b/include/linux/trace_recursion.h
> @@ -142,7 +142,28 @@ static __always_inline int trace_get_context_bit(void)
> pc & HARDIRQ_MASK ? TRACE_CTX_IRQ : TRACE_CTX_SOFTIRQ;
> }
>
> -static __always_inline int trace_test_and_set_recursion(int start, int max)
> +#ifdef CONFIG_FTRACE_RECORD_RECURSION
> +extern void ftrace_record_recursion(unsigned long ip, unsigned long parent_ip);
> +/*
> +* The paranoid_test check can cause dropped reports (unlikely), but
> +* if the recursion is common, it will likely still be recorded later.
> +* But the paranoid_test is needed to make sure we don't crash.
> +*/
> +# define do_ftrace_record_recursion(ip, pip) \
> + do { \
> + static atomic_t paranoid_test; \
> + if (!atomic_read(¶noid_test)) { \
> + atomic_inc(¶noid_test); \
> + ftrace_record_recursion(ip, pip); \
> + atomic_dec(¶noid_test); \
BTW: What is actually the purpose of paranoid_test, please?
It prevents nested ftrace_record_recursion() calls on the same CPU
(recursion, nesting from IRQ, NMI context).
Parallel calls from different CPUs are still possible:
CPU0 CPU1
if (!atomic_read(¶noid_test)) if (!atomic_read(¶noid_test))
// passes // passes
atomic_inc(¶noid_test); atomic_inc(¶noid_test);
I do not see how a nested call could cause crash while a parallel
one would be OK.
> --- /dev/null
> +++ b/kernel/trace/trace_recursion_record.c
> @@ -0,0 +1,236 @@
> +// SPDX-License-Identifier: GPL-2.0
> +
> +#include <linux/seq_file.h>
> +#include <linux/kallsyms.h>
> +#include <linux/module.h>
> +#include <linux/ftrace.h>
> +#include <linux/fs.h>
> +
> +#include "trace_output.h"
> +
> +struct recursed_functions {
> + unsigned long ip;
> + unsigned long parent_ip;
> +};
> +
> +static struct recursed_functions recursed_functions[CONFIG_FTRACE_RECORD_RECURSION_SIZE];
> +static atomic_t nr_records;
> +
> +/*
> + * Cache the last found function. Yes, updates to this is racey, but
> + * so is memory cache ;-)
> + */
> +static unsigned long cached_function;
> +
> +void ftrace_record_recursion(unsigned long ip, unsigned long parent_ip)
> +{
> + int index = 0;
> + int i;
> + unsigned long old;
> +
> + again:
> + /* First check the last one recorded */
> + if (ip == cached_function)
> + return;
> +
> + i = atomic_read(&nr_records);
> + /* nr_records is -1 when clearing records */
> + smp_mb__after_atomic();
> + if (i < 0)
> + return;
> +
> + /*
> + * If there's two writers and this writer comes in second,
> + * the cmpxchg() below to update the ip will fail. Then this
> + * writer will try again. It is possible that index will now
> + * be greater than nr_records. This is because the writer
> + * that succeeded has not updated the nr_records yet.
> + * This writer could keep trying again until the other writer
> + * updates nr_records. But if the other writer takes an
> + * interrupt, and that interrupt locks up that CPU, we do
> + * not want this CPU to lock up due to the recursion protection,
> + * and have a bug report showing this CPU as the cause of
> + * locking up the computer. To not lose this record, this
> + * writer will simply use the next position to update the
> + * recursed_functions, and it will update the nr_records
> + * accordingly.
> + */
> + if (index < i)
> + index = i;
> + if (index >= CONFIG_FTRACE_RECORD_RECURSION_SIZE)
> + return;
> +
> + for (i = index - 1; i >= 0; i--) {
> + if (recursed_functions[i].ip == ip) {
> + cached_function = ip;
> + return;
> + }
> + }
> +
> + cached_function = ip;
> +
> + /*
> + * We only want to add a function if it hasn't been added before.
> + * Add to the current location before incrementing the count.
> + * If it fails to add, then increment the index (save in i)
> + * and try again.
> + */
> + old = cmpxchg(&recursed_functions[index].ip, 0, ip);
> + if (old != 0) {
> + /* Did something else already added this for us? */
> + if (old == ip)
> + return;
> + /* Try the next location (use i for the next index) */
> + index++;
> + goto again;
> + }
> +
> + recursed_functions[index].parent_ip = parent_ip;
> +
> + /*
> + * It's still possible that we could race with the clearing
> + * CPU0 CPU1
> + * ---- ----
> + * ip = func
> + * nr_records = -1;
> + * recursed_functions[0] = 0;
> + * i = -1
> + * if (i < 0)
> + * nr_records = 0;
> + * (new recursion detected)
> + * recursed_functions[0] = func
> + * cmpxchg(recursed_functions[0],
> + * func, 0)
> + *
> + * But the worse that could happen is that we get a zero in
> + * the recursed_functions array, and it's likely that "func" will
> + * be recorded again.
> + */
> + i = atomic_read(&nr_records);
> + smp_mb__after_atomic();
> + if (i < 0)
> + cmpxchg(&recursed_functions[index].ip, ip, 0);
> + else if (i <= index)
> + atomic_cmpxchg(&nr_records, i, index + 1);
Are you aware of the following race, please?
CPU0 CPU1
ftrace_record_recursion()
i = atomic_read(&nr_records);
// i = 20 (for example)
if (i < index)
index = i;
// index = 20;
recursed_function_open()
atomic_set(&nr_records, -1);
memset(recursed_functions, 0, );
atomic_set(&nr_records, 0);
// successfully store ip at index == 20
cmpxchg(&recursed_functions[index].ip, 0, ip);
recursed_functions[index].parent_ip = parent_ip;
// check race with clearing
i = atomic_read(&nr_records);
// i == 0
if (i < 0)
// no
else
atomic_cmpxchg(&nr_records, i, index + 1);
RESULT:
+ nr_records == 21
+ and slots 0..19 are zeroed
I played with the code and ended with head entangled by chicken & egg
like problems.
I believe that a solution might be a combined atomic variable from
nr_records + cleanup_count.
ftrace_record_recursion() would be allowed to increase nr_records
only when cleanup_count is still the same. cleanup_count would
be incremented together with clearing nr_records.
Well, I am not sure if it is worth the effort. The race is rather
theoretical. In the worst case, the cache might contain many
zero values.
Anyway, it is yet another experience for me that lockless algorithms
are more tricky that one would expect.
Best Regards,
Petr
^ permalink raw reply
* [PATCH] powerpc: Don't use asm goto for put_user() with GCC 4.9
From: Michael Ellerman @ 2020-11-03 13:29 UTC (permalink / raw)
To: linuxppc-dev; +Cc: schwab
Andreas reported that commit ee0a49a6870e ("powerpc/uaccess: Switch
__put_user_size_allowed() to __put_user_asm_goto()") broke
CLONE_CHILD_SETTID.
Further inspection showed that the put_user() in schedule_tail() was
missing entirely, the store not emitted by the compiler.
<.schedule_tail>:
mflr r0
std r0,16(r1)
stdu r1,-112(r1)
bl <.finish_task_switch>
ld r9,2496(r3)
cmpdi cr7,r9,0
bne cr7,<.schedule_tail+0x60>
ld r3,392(r13)
ld r9,1392(r3)
cmpdi cr7,r9,0
beq cr7,<.schedule_tail+0x3c>
li r4,0
li r5,0
bl <.__task_pid_nr_ns>
nop
bl <.calculate_sigpending>
nop
addi r1,r1,112
ld r0,16(r1)
mtlr r0
blr
nop
nop
nop
bl <.__balance_callback>
b <.schedule_tail+0x1c>
Notice there are no stores other than to the stack. There should be a
stw in there for the store to current->set_child_tid.
This is only seen with GCC 4.9 era compilers (tested with 4.9.3 and
4.9.4), and only when CONFIG_PPC_KUAP is disabled.
When CONFIG_PPC_KUAP=y, the memory clobber that's part of the isync()
and mtspr() inlined via allow_user_access() seems to be enough to
avoid the bug.
For now though let's just not use asm goto with GCC 4.9, to avoid this
bug and any other issues we haven't noticed yet. Possibly in future we
can find a smaller workaround.
This is basically a revert of commit ee0a49a6870e ("powerpc/uaccess:
Switch __put_user_size_allowed() to __put_user_asm_goto()") and commit
7fdf966bed15 ("powerpc/uaccess: Remove __put_user_asm() and
__put_user_asm2()"), but only for GCC 4.9.
With this applied the code generation looks more like it will work:
<.schedule_tail>:
mflr r0
std r31,-8(r1)
std r0,16(r1)
stdu r1,-144(r1)
std r3,112(r1)
bl <._mcount>
nop
ld r3,112(r1)
bl <.finish_task_switch>
ld r9,2624(r3)
cmpdi cr7,r9,0
bne cr7,<.schedule_tail+0xa0>
ld r3,2408(r13)
ld r31,1856(r3)
cmpdi cr7,r31,0
beq cr7,<.schedule_tail+0x80>
li r4,0
li r5,0
bl <.__task_pid_nr_ns>
nop
li r9,-1
clrldi r9,r9,12
cmpld cr7,r31,r9
bgt cr7,<.schedule_tail+0x80>
lis r9,16
rldicr r9,r9,32,31
subf r9,r31,r9
cmpldi cr7,r9,3
ble cr7,<.schedule_tail+0x80>
li r9,0
stw r3,0(r31) <-- stw
nop
bl <.calculate_sigpending>
nop
addi r1,r1,144
ld r0,16(r1)
ld r31,-8(r1)
mtlr r0
blr
nop
bl <.__balance_callback>
b <.schedule_tail+0x30>
Fixes: ee0a49a6870e ("powerpc/uaccess: Switch __put_user_size_allowed() to __put_user_asm_goto()")
Reported-by: Andreas Schwab <schwab@linux-m68k.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
---
arch/powerpc/include/asm/uaccess.h | 48 ++++++++++++++++++++++++++++++
1 file changed, 48 insertions(+)
diff --git a/arch/powerpc/include/asm/uaccess.h b/arch/powerpc/include/asm/uaccess.h
index ef5bbb705c08..526a6658946b 100644
--- a/arch/powerpc/include/asm/uaccess.h
+++ b/arch/powerpc/include/asm/uaccess.h
@@ -110,6 +110,52 @@ static inline bool __access_ok(unsigned long addr, unsigned long size)
extern long __put_user_bad(void);
+#if defined(GCC_VERSION) && GCC_VERSION < 50000
+#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 { \
+ 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(); \
+ } \
+} while (0)
+
+#else
+
#define __put_user_size_allowed(x, ptr, size, retval) \
do { \
__label__ __pu_failed; \
@@ -122,6 +168,8 @@ __pu_failed: \
retval = -EFAULT; \
} while (0)
+#endif /* GCC_VERSION */
+
#define __put_user_size(x, ptr, size, retval) \
do { \
allow_write_to_user(ptr, size); \
--
2.25.1
^ permalink raw reply related
* Re: [PATCH 1/3] powerpc/uaccess: Switch __put_user_size_allowed() to __put_user_asm_goto()
From: Michael Ellerman @ 2020-11-03 13:21 UTC (permalink / raw)
To: Andreas Schwab; +Cc: Paul Mackerras, linuxppc-dev, linux-kernel
In-Reply-To: <871rhgwzcg.fsf@igel.home>
Andreas Schwab <schwab@linux-m68k.org> writes:
> #
> # Automatically generated file; DO NOT EDIT.
> # Linux/powerpc 5.10.0-rc1 Kernel Configuration
> #
> CONFIG_CC_VERSION_TEXT="gcc-4.9 (SUSE Linux) 4.9.3"
So it seems to be a combination of GCC 4.9 and ...
> # CONFIG_PPC_RADIX_MMU is not set
That ^, which specifically causes PPC_KUAP=n.
When PPC_KUAP=y allow_user_access() inlines an isync and mtspr, both of
which contain a memory clobber, and that seems to hide the bug.
I think for now we just have to stop using asm goto for put_user() on
GCC 4.9.
I'll send a patch for that.
cheers
^ permalink raw reply
* Re: [PATCH v3 2/4] PM: hibernate: make direct map manipulations more explicit
From: Mike Rapoport @ 2020-11-03 12:13 UTC (permalink / raw)
To: Kirill A. Shutemov
Cc: Rafael J . Wysocki, David Hildenbrand, Peter Zijlstra,
Dave Hansen, linux-mm, Paul Mackerras, Pavel Machek,
H. Peter Anvin, sparclinux, Christoph Lameter, Will Deacon,
linux-riscv, linux-s390, x86, Mike Rapoport,
Christian Borntraeger, Ingo Molnar, Catalin Marinas, Len Brown,
Albert Ou, Vasily Gorbik, linux-pm, Heiko Carstens,
David Rientjes, Borislav Petkov, Andy Lutomirski, Paul Walmsley,
Thomas Gleixner, Joonsoo Kim, linux-arm-kernel, Rafael J. Wysocki,
linux-kernel, Pekka Enberg, Palmer Dabbelt, Andrew Morton,
Edgecombe, Rick P, linuxppc-dev, David S. Miller
In-Reply-To: <20201103110816.t6a3ebtgcm7mfogy@box>
On Tue, Nov 03, 2020 at 02:08:16PM +0300, Kirill A. Shutemov wrote:
> On Sun, Nov 01, 2020 at 07:08:13PM +0200, Mike Rapoport wrote:
> > diff --git a/kernel/power/snapshot.c b/kernel/power/snapshot.c
> > index 46b1804c1ddf..054c8cce4236 100644
> > --- a/kernel/power/snapshot.c
> > +++ b/kernel/power/snapshot.c
> > @@ -76,6 +76,32 @@ static inline void hibernate_restore_protect_page(void *page_address) {}
> > static inline void hibernate_restore_unprotect_page(void *page_address) {}
> > #endif /* CONFIG_STRICT_KERNEL_RWX && CONFIG_ARCH_HAS_SET_MEMORY */
> >
> > +static inline void hibernate_map_page(struct page *page, int enable)
> > +{
> > + if (IS_ENABLED(CONFIG_ARCH_HAS_SET_DIRECT_MAP)) {
> > + unsigned long addr = (unsigned long)page_address(page);
> > + int ret;
> > +
> > + /*
> > + * This should not fail because remapping a page here means
> > + * that we only update protection bits in an existing PTE.
> > + * It is still worth to have WARN_ON() here if something
> > + * changes and this will no longer be the case.
> > + */
> > + if (enable)
> > + ret = set_direct_map_default_noflush(page);
> > + else
> > + ret = set_direct_map_invalid_noflush(page);
> > +
> > + if (WARN_ON(ret))
>
> _ONCE?
I've changed it to pr_warn() after David said people enable panic on
warn in production kernels.
> > + return;
> > +
> > + flush_tlb_kernel_range(addr, addr + PAGE_SIZE);
> > + } else {
> > + debug_pagealloc_map_pages(page, 1, enable);
> > + }
> > +}
> > +
> > static int swsusp_page_is_free(struct page *);
> > static void swsusp_set_page_forbidden(struct page *);
> > static void swsusp_unset_page_forbidden(struct page *);
>
> --
> Kirill A. Shutemov
--
Sincerely yours,
Mike.
^ permalink raw reply
* Re: [PATCH 05/11 v2] kprobes/ftrace: Add recursion protection to the ftrace callback
From: Masami Hiramatsu @ 2020-11-03 11:22 UTC (permalink / raw)
To: Steven Rostedt
Cc: Peter Zijlstra, James E.J. Bottomley, Guo Ren, linux-csky,
H. Peter Anvin, Miroslav Benes, Ingo Molnar, linux-s390,
Helge Deller, x86, Anil S Keshavamurthy, Christian Borntraeger,
Naveen N. Rao, Petr Mladek, Vasily Gorbik, Heiko Carstens,
Jiri Kosina, Borislav Petkov, Josh Poimboeuf, Thomas Gleixner,
linux-parisc, linux-kernel, Masami Hiramatsu, Paul Mackerras,
Andrew Morton, linuxppc-dev, David S. Miller
In-Reply-To: <20201030214013.824581418@goodmis.org>
On Fri, 30 Oct 2020 17:31:47 -0400
Steven Rostedt <rostedt@goodmis.org> wrote:
> From: "Steven Rostedt (VMware)" <rostedt@goodmis.org>
>
> If a ftrace callback does not supply its own recursion protection and
> does not set the RECURSION_SAFE flag in its ftrace_ops, then ftrace will
> make a helper trampoline to do so before calling the callback instead of
> just calling the callback directly.
>
> The default for ftrace_ops is going to change. It will expect that handlers
> provide their own recursion protection, unless its ftrace_ops states
> otherwise.
>
> Link: https://lkml.kernel.org/r/20201028115613.140212174@goodmis.org
>
> Cc: Andrew Morton <akpm@linux-foundation.org>
> Cc: Masami Hiramatsu <mhiramat@kernel.org>
> Cc: Guo Ren <guoren@kernel.org>
> Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
> Cc: Helge Deller <deller@gmx.de>
> Cc: Michael Ellerman <mpe@ellerman.id.au>
> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
> Cc: Paul Mackerras <paulus@samba.org>
> Cc: Heiko Carstens <hca@linux.ibm.com>
> Cc: Vasily Gorbik <gor@linux.ibm.com>
> Cc: Christian Borntraeger <borntraeger@de.ibm.com>
> Cc: Thomas Gleixner <tglx@linutronix.de>
> Cc: Borislav Petkov <bp@alien8.de>
> Cc: x86@kernel.org
> Cc: "H. Peter Anvin" <hpa@zytor.com>
> Cc: "Naveen N. Rao" <naveen.n.rao@linux.ibm.com>
> Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
> Cc: "David S. Miller" <davem@davemloft.net>
> Cc: linux-csky@vger.kernel.org
> Cc: linux-parisc@vger.kernel.org
> Cc: linuxppc-dev@lists.ozlabs.org
> Cc: linux-s390@vger.kernel.org
> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
> ---
> arch/csky/kernel/probes/ftrace.c | 12 ++++++++++--
> arch/parisc/kernel/ftrace.c | 13 +++++++++++--
> arch/powerpc/kernel/kprobes-ftrace.c | 11 ++++++++++-
> arch/s390/kernel/ftrace.c | 13 +++++++++++--
> arch/x86/kernel/kprobes/ftrace.c | 12 ++++++++++--
> 5 files changed, 52 insertions(+), 9 deletions(-)
>
> diff --git a/arch/csky/kernel/probes/ftrace.c b/arch/csky/kernel/probes/ftrace.c
> index 5264763d05be..5eb2604fdf71 100644
> --- a/arch/csky/kernel/probes/ftrace.c
> +++ b/arch/csky/kernel/probes/ftrace.c
> @@ -13,16 +13,21 @@ int arch_check_ftrace_location(struct kprobe *p)
> void kprobe_ftrace_handler(unsigned long ip, unsigned long parent_ip,
> struct ftrace_ops *ops, struct pt_regs *regs)
> {
> + int bit;
> bool lr_saver = false;
> struct kprobe *p;
> struct kprobe_ctlblk *kcb;
>
> - /* Preempt is disabled by ftrace */
> + bit = ftrace_test_recursion_trylock();
> + if (bit < 0)
> + return;
> +
> + preempt_disable_notrace();
> p = get_kprobe((kprobe_opcode_t *)ip);
> if (!p) {
> p = get_kprobe((kprobe_opcode_t *)(ip - MCOUNT_INSN_SIZE));
> if (unlikely(!p) || kprobe_disabled(p))
> - return;
> + goto out;
> lr_saver = true;
> }
>
> @@ -56,6 +61,9 @@ void kprobe_ftrace_handler(unsigned long ip, unsigned long parent_ip,
> */
> __this_cpu_write(current_kprobe, NULL);
> }
> +out:
> + preempt_enable_notrace();
> + ftrace_test_recursion_unlock(bit);
> }
> NOKPROBE_SYMBOL(kprobe_ftrace_handler);
>
> diff --git a/arch/parisc/kernel/ftrace.c b/arch/parisc/kernel/ftrace.c
> index 63e3ecb9da81..4b1fdf15662c 100644
> --- a/arch/parisc/kernel/ftrace.c
> +++ b/arch/parisc/kernel/ftrace.c
> @@ -208,13 +208,19 @@ void kprobe_ftrace_handler(unsigned long ip, unsigned long parent_ip,
> {
> struct kprobe_ctlblk *kcb;
> struct kprobe *p = get_kprobe((kprobe_opcode_t *)ip);
> + int bit;
>
> - if (unlikely(!p) || kprobe_disabled(p))
> + bit = ftrace_test_recursion_trylock();
> + if (bit < 0)
> return;
>
> + preempt_disable_notrace();
If we disable preempt here, we also move the get_kprobe() here as below.
(get_kprobe() accesses percpu variable)
p = get_kprobe((kprobe_opcode_t *)ip);
> + if (unlikely(!p) || kprobe_disabled(p))
> + goto out;
> +
> if (kprobe_running()) {
> kprobes_inc_nmissed_count(p);
> - return;
> + goto out;
> }
>
> __this_cpu_write(current_kprobe, p);
> @@ -235,6 +241,9 @@ void kprobe_ftrace_handler(unsigned long ip, unsigned long parent_ip,
> }
> }
> __this_cpu_write(current_kprobe, NULL);
> +out:
> + preempt_enable_notrace();
> + ftrace_test_recursion_unlock(bit);
> }
> NOKPROBE_SYMBOL(kprobe_ftrace_handler);
>
> diff --git a/arch/powerpc/kernel/kprobes-ftrace.c b/arch/powerpc/kernel/kprobes-ftrace.c
> index 972cb28174b2..5df8d50c65ae 100644
> --- a/arch/powerpc/kernel/kprobes-ftrace.c
> +++ b/arch/powerpc/kernel/kprobes-ftrace.c
> @@ -18,10 +18,16 @@ void kprobe_ftrace_handler(unsigned long nip, unsigned long parent_nip,
> {
> struct kprobe *p;
> struct kprobe_ctlblk *kcb;
> + int bit;
>
> + bit = ftrace_test_recursion_trylock();
> + if (bit < 0)
> + return;
> +
> + preempt_disable_notrace();
> p = get_kprobe((kprobe_opcode_t *)nip);
> if (unlikely(!p) || kprobe_disabled(p))
> - return;
> + goto out;
>
> kcb = get_kprobe_ctlblk();
> if (kprobe_running()) {
> @@ -52,6 +58,9 @@ void kprobe_ftrace_handler(unsigned long nip, unsigned long parent_nip,
> */
> __this_cpu_write(current_kprobe, NULL);
> }
> +out:
> + preempt_enable_notrace();
> + ftrace_test_recursion_unlock(bit);
> }
> NOKPROBE_SYMBOL(kprobe_ftrace_handler);
>
> diff --git a/arch/s390/kernel/ftrace.c b/arch/s390/kernel/ftrace.c
> index b388e87a08bf..88466d7fb6b2 100644
> --- a/arch/s390/kernel/ftrace.c
> +++ b/arch/s390/kernel/ftrace.c
> @@ -202,13 +202,19 @@ void kprobe_ftrace_handler(unsigned long ip, unsigned long parent_ip,
> {
> struct kprobe_ctlblk *kcb;
> struct kprobe *p = get_kprobe((kprobe_opcode_t *)ip);
> + int bit;
>
> - if (unlikely(!p) || kprobe_disabled(p))
> + bit = ftrace_test_recursion_trylock();
> + if (bit < 0)
> return;
>
> + preempt_disable_notrace();
Ditto.
Others look good to me.
Thank you,
> + if (unlikely(!p) || kprobe_disabled(p))
> + goto out;
> +
> if (kprobe_running()) {
> kprobes_inc_nmissed_count(p);
> - return;
> + goto out;
> }
>
> __this_cpu_write(current_kprobe, p);
> @@ -228,6 +234,9 @@ void kprobe_ftrace_handler(unsigned long ip, unsigned long parent_ip,
> }
> }
> __this_cpu_write(current_kprobe, NULL);
> +out:
> + preempt_enable_notrace();
> + ftrace_test_recursion_unlock(bit);
> }
> NOKPROBE_SYMBOL(kprobe_ftrace_handler);
>
> diff --git a/arch/x86/kernel/kprobes/ftrace.c b/arch/x86/kernel/kprobes/ftrace.c
> index 681a4b36e9bb..a40a6cdfcca3 100644
> --- a/arch/x86/kernel/kprobes/ftrace.c
> +++ b/arch/x86/kernel/kprobes/ftrace.c
> @@ -18,11 +18,16 @@ void kprobe_ftrace_handler(unsigned long ip, unsigned long parent_ip,
> {
> struct kprobe *p;
> struct kprobe_ctlblk *kcb;
> + int bit;
>
> - /* Preempt is disabled by ftrace */
> + bit = ftrace_test_recursion_trylock();
> + if (bit < 0)
> + return;
> +
> + preempt_disable_notrace();
> p = get_kprobe((kprobe_opcode_t *)ip);
> if (unlikely(!p) || kprobe_disabled(p))
> - return;
> + goto out;
>
> kcb = get_kprobe_ctlblk();
> if (kprobe_running()) {
> @@ -52,6 +57,9 @@ void kprobe_ftrace_handler(unsigned long ip, unsigned long parent_ip,
> */
> __this_cpu_write(current_kprobe, NULL);
> }
> +out:
> + preempt_enable_notrace();
> + ftrace_test_recursion_unlock(bit);
> }
> NOKPROBE_SYMBOL(kprobe_ftrace_handler);
>
> --
> 2.28.0
>
>
--
Masami Hiramatsu <mhiramat@kernel.org>
^ permalink raw reply
* Re: [PATCH v3 0/4] arch, mm: improve robustness of direct map manipulation
From: Kirill A. Shutemov @ 2020-11-03 11:15 UTC (permalink / raw)
To: Mike Rapoport
Cc: David Hildenbrand, Peter Zijlstra, Dave Hansen, linux-mm,
Paul Mackerras, Pavel Machek, H. Peter Anvin, sparclinux,
Christoph Lameter, Will Deacon, linux-riscv, linux-s390, x86,
Mike Rapoport, Christian Borntraeger, Ingo Molnar,
Catalin Marinas, Len Brown, Albert Ou, Vasily Gorbik, linux-pm,
Heiko Carstens, David Rientjes, Borislav Petkov, Andy Lutomirski,
Paul Walmsley, Thomas Gleixner, Joonsoo Kim, linux-arm-kernel,
Rafael J. Wysocki, linux-kernel, Pekka Enberg, Palmer Dabbelt,
Andrew Morton, Edgecombe, Rick P, linuxppc-dev, David S. Miller
In-Reply-To: <20201101170815.9795-1-rppt@kernel.org>
On Sun, Nov 01, 2020 at 07:08:11PM +0200, Mike Rapoport wrote:
> Mike Rapoport (4):
> mm: introduce debug_pagealloc_map_pages() helper
> PM: hibernate: make direct map manipulations more explicit
> arch, mm: restore dependency of __kernel_map_pages() of DEBUG_PAGEALLOC
> arch, mm: make kernel_page_present() always available
The series looks good to me (apart from the minor nit):
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
--
Kirill A. Shutemov
^ permalink raw reply
* Re: [PATCH v3 2/4] PM: hibernate: make direct map manipulations more explicit
From: Kirill A. Shutemov @ 2020-11-03 11:08 UTC (permalink / raw)
To: Mike Rapoport
Cc: Rafael J . Wysocki, David Hildenbrand, Peter Zijlstra,
Dave Hansen, linux-mm, Paul Mackerras, Pavel Machek,
H. Peter Anvin, sparclinux, Christoph Lameter, Will Deacon,
linux-riscv, linux-s390, x86, Mike Rapoport,
Christian Borntraeger, Ingo Molnar, Catalin Marinas, Len Brown,
Albert Ou, Vasily Gorbik, linux-pm, Heiko Carstens,
David Rientjes, Borislav Petkov, Andy Lutomirski, Paul Walmsley,
Thomas Gleixner, Joonsoo Kim, linux-arm-kernel, Rafael J. Wysocki,
linux-kernel, Pekka Enberg, Palmer Dabbelt, Andrew Morton,
Edgecombe, Rick P, linuxppc-dev, David S. Miller
In-Reply-To: <20201101170815.9795-3-rppt@kernel.org>
On Sun, Nov 01, 2020 at 07:08:13PM +0200, Mike Rapoport wrote:
> diff --git a/kernel/power/snapshot.c b/kernel/power/snapshot.c
> index 46b1804c1ddf..054c8cce4236 100644
> --- a/kernel/power/snapshot.c
> +++ b/kernel/power/snapshot.c
> @@ -76,6 +76,32 @@ static inline void hibernate_restore_protect_page(void *page_address) {}
> static inline void hibernate_restore_unprotect_page(void *page_address) {}
> #endif /* CONFIG_STRICT_KERNEL_RWX && CONFIG_ARCH_HAS_SET_MEMORY */
>
> +static inline void hibernate_map_page(struct page *page, int enable)
> +{
> + if (IS_ENABLED(CONFIG_ARCH_HAS_SET_DIRECT_MAP)) {
> + unsigned long addr = (unsigned long)page_address(page);
> + int ret;
> +
> + /*
> + * This should not fail because remapping a page here means
> + * that we only update protection bits in an existing PTE.
> + * It is still worth to have WARN_ON() here if something
> + * changes and this will no longer be the case.
> + */
> + if (enable)
> + ret = set_direct_map_default_noflush(page);
> + else
> + ret = set_direct_map_invalid_noflush(page);
> +
> + if (WARN_ON(ret))
_ONCE?
> + return;
> +
> + flush_tlb_kernel_range(addr, addr + PAGE_SIZE);
> + } else {
> + debug_pagealloc_map_pages(page, 1, enable);
> + }
> +}
> +
> static int swsusp_page_is_free(struct page *);
> static void swsusp_set_page_forbidden(struct page *);
> static void swsusp_unset_page_forbidden(struct page *);
--
Kirill A. Shutemov
^ permalink raw reply
* [Bug 209869] Kernel 5.10-rc1 fails to boot on a PowerMac G4 3,6 at an early stage
From: bugzilla-daemon @ 2020-11-03 11:06 UTC (permalink / raw)
To: linuxppc-dev
In-Reply-To: <bug-209869-206035@https.bugzilla.kernel.org/>
https://bugzilla.kernel.org/show_bug.cgi?id=209869
--- Comment #2 from Erhard F. (erhard_f@mailbox.org) ---
Yes, reverting this commit (on top of -rc1) makes the G4 boot again. Did not
try -rc2 though.
--
You are receiving this mail because:
You are watching the assignee of the bug.
^ permalink raw reply
* [patch V3 37/37] io-mapping: Remove io_mapping_map_atomic_wc()
From: Thomas Gleixner @ 2020-11-03 9:27 UTC (permalink / raw)
To: LKML
Cc: Juri Lelli, linux-aio, Peter Zijlstra, Sebastian Andrzej Siewior,
Joonas Lahtinen, dri-devel, virtualization, Ben Segall,
Chris Mason, Huang Rui, Paul Mackerras, Gerd Hoffmann,
Daniel Bristot de Oliveira, sparclinux, Vincent Chen,
Christoph Hellwig, Vincent Guittot, Paul McKenney, Max Filippov,
x86, Russell King, linux-csky, Ingo Molnar, David Airlie,
VMware Graphics, Mel Gorman, nouveau, Dave Airlie, linux-snps-arc,
Ben Skeggs, linux-xtensa, Arnd Bergmann, intel-gfx,
Roland Scheidegger, Josef Bacik, Steven Rostedt, Linus Torvalds,
Alexander Viro, spice-devel, David Sterba, Rodrigo Vivi,
Dietmar Eggemann, linux-arm-kernel, Jani Nikula, Chris Zankel,
Michal Simek, Thomas Bogendoerfer, Nick Hu, linux-mm,
Vineet Gupta, linux-mips, Christian Koenig, Benjamin LaHaise,
Daniel Vetter, linux-fsdevel, Andrew Morton, linuxppc-dev,
David S. Miller, linux-btrfs, Greentime Hu
In-Reply-To: <20201103092712.714480842@linutronix.de>
No more users. Get rid of it and remove the traces in documentation.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---
V3: New patch
---
Documentation/driver-api/io-mapping.rst | 22 +++++-----------
include/linux/io-mapping.h | 42 +-------------------------------
2 files changed, 9 insertions(+), 55 deletions(-)
--- a/Documentation/driver-api/io-mapping.rst
+++ b/Documentation/driver-api/io-mapping.rst
@@ -21,19 +21,15 @@ mappable, while 'size' indicates how lar
enable. Both are in bytes.
This _wc variant provides a mapping which may only be used with
-io_mapping_map_atomic_wc(), io_mapping_map_local_wc() or
-io_mapping_map_wc().
+io_mapping_map_local_wc() or io_mapping_map_wc().
With this mapping object, individual pages can be mapped either temporarily
or long term, depending on the requirements. Of course, temporary maps are
-more efficient. They come in two flavours::
+more efficient.
void *io_mapping_map_local_wc(struct io_mapping *mapping,
unsigned long offset)
- void *io_mapping_map_atomic_wc(struct io_mapping *mapping,
- unsigned long offset)
-
'offset' is the offset within the defined mapping region. Accessing
addresses beyond the region specified in the creation function yields
undefined results. Using an offset which is not page aligned yields an
@@ -50,9 +46,6 @@ io_mapping_map_local_wc() has a side eff
migration to make the mapping code work. No caller can rely on this side
effect.
-io_mapping_map_atomic_wc() has the side effect of disabling preemption and
-pagefaults. Don't use in new code. Use io_mapping_map_local_wc() instead.
-
Nested mappings need to be undone in reverse order because the mapping
code uses a stack for keeping track of them::
@@ -65,11 +58,10 @@ Nested mappings need to be undone in rev
The mappings are released with::
void io_mapping_unmap_local(void *vaddr)
- void io_mapping_unmap_atomic(void *vaddr)
-'vaddr' must be the value returned by the last io_mapping_map_local_wc() or
-io_mapping_map_atomic_wc() call. This unmaps the specified mapping and
-undoes the side effects of the mapping functions.
+'vaddr' must be the value returned by the last io_mapping_map_local_wc()
+call. This unmaps the specified mapping and undoes eventual side effects of
+the mapping function.
If you need to sleep while holding a mapping, you can use the regular
variant, although this may be significantly slower::
@@ -77,8 +69,8 @@ If you need to sleep while holding a map
void *io_mapping_map_wc(struct io_mapping *mapping,
unsigned long offset)
-This works like io_mapping_map_atomic/local_wc() except it has no side
-effects and the pointer is globaly visible.
+This works like io_mapping_map_local_wc() except it has no side effects and
+the pointer is globaly visible.
The mappings are released with::
--- a/include/linux/io-mapping.h
+++ b/include/linux/io-mapping.h
@@ -60,28 +60,7 @@ io_mapping_fini(struct io_mapping *mappi
iomap_free(mapping->base, mapping->size);
}
-/* Atomic map/unmap */
-static inline void __iomem *
-io_mapping_map_atomic_wc(struct io_mapping *mapping,
- unsigned long offset)
-{
- resource_size_t phys_addr;
-
- BUG_ON(offset >= mapping->size);
- phys_addr = mapping->base + offset;
- preempt_disable();
- pagefault_disable();
- return __iomap_local_pfn_prot(PHYS_PFN(phys_addr), mapping->prot);
-}
-
-static inline void
-io_mapping_unmap_atomic(void __iomem *vaddr)
-{
- kunmap_local_indexed((void __force *)vaddr);
- pagefault_enable();
- preempt_enable();
-}
-
+/* Temporary mappings which are only valid in the current context */
static inline void __iomem *
io_mapping_map_local_wc(struct io_mapping *mapping, unsigned long offset)
{
@@ -163,24 +142,7 @@ io_mapping_unmap(void __iomem *vaddr)
{
}
-/* Atomic map/unmap */
-static inline void __iomem *
-io_mapping_map_atomic_wc(struct io_mapping *mapping,
- unsigned long offset)
-{
- preempt_disable();
- pagefault_disable();
- return io_mapping_map_wc(mapping, offset, PAGE_SIZE);
-}
-
-static inline void
-io_mapping_unmap_atomic(void __iomem *vaddr)
-{
- io_mapping_unmap(vaddr);
- pagefault_enable();
- preempt_enable();
-}
-
+/* Temporary mappings which are only valid in the current context */
static inline void __iomem *
io_mapping_map_local_wc(struct io_mapping *mapping, unsigned long offset)
{
^ permalink raw reply
* [patch V3 36/37] drm/i915: Replace io_mapping_map_atomic_wc()
From: Thomas Gleixner @ 2020-11-03 9:27 UTC (permalink / raw)
To: LKML
Cc: Juri Lelli, linux-aio, Peter Zijlstra, Sebastian Andrzej Siewior,
Joonas Lahtinen, dri-devel, virtualization, Ben Segall, linux-mm,
Huang Rui, Paul Mackerras, Gerd Hoffmann,
Daniel Bristot de Oliveira, sparclinux, Dave Airlie, Vincent Chen,
Christoph Hellwig, Vincent Guittot, Arnd Bergmann, Max Filippov,
x86, Russell King, linux-csky, Ingo Molnar, David Airlie,
Steven Rostedt, Mel Gorman, nouveau, VMware Graphics,
linux-snps-arc, Ben Skeggs, linux-xtensa, Paul McKenney,
intel-gfx, Roland Scheidegger, Josef Bacik, Jani Nikula,
Linus Torvalds, Alexander Viro, Rodrigo Vivi, David Sterba,
Dietmar Eggemann, linux-arm-kernel, Chris Zankel, Michal Simek,
Thomas Bogendoerfer, Nick Hu, Chris Mason, Vineet Gupta,
linux-mips, Christian Koenig, Benjamin LaHaise, spice-devel,
Daniel Vetter, linux-fsdevel, Andrew Morton, linuxppc-dev,
David S. Miller, linux-btrfs, Greentime Hu
In-Reply-To: <20201103092712.714480842@linutronix.de>
None of these mapping requires the side effect of disabling pagefaults and
preemption.
Use io_mapping_map_local_wc() instead, and clean up gtt_user_read() and
gtt_user_write() to use a plain copy_from_user() as the local maps are not
disabling pagefaults.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: intel-gfx@lists.freedesktop.org
Cc: dri-devel@lists.freedesktop.org
---
V3: New patch
---
drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c | 7 +---
drivers/gpu/drm/i915/i915_gem.c | 40 ++++++++-----------------
drivers/gpu/drm/i915/selftests/i915_gem.c | 4 +-
drivers/gpu/drm/i915/selftests/i915_gem_gtt.c | 8 ++---
4 files changed, 22 insertions(+), 37 deletions(-)
--- a/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c
@@ -1081,7 +1081,7 @@ static void reloc_cache_reset(struct rel
struct i915_ggtt *ggtt = cache_to_ggtt(cache);
intel_gt_flush_ggtt_writes(ggtt->vm.gt);
- io_mapping_unmap_atomic((void __iomem *)vaddr);
+ io_mapping_unmap_local((void __iomem *)vaddr);
if (drm_mm_node_allocated(&cache->node)) {
ggtt->vm.clear_range(&ggtt->vm,
@@ -1147,7 +1147,7 @@ static void *reloc_iomap(struct drm_i915
if (cache->vaddr) {
intel_gt_flush_ggtt_writes(ggtt->vm.gt);
- io_mapping_unmap_atomic((void __force __iomem *) unmask_page(cache->vaddr));
+ io_mapping_unmap_local((void __force __iomem *) unmask_page(cache->vaddr));
} else {
struct i915_vma *vma;
int err;
@@ -1195,8 +1195,7 @@ static void *reloc_iomap(struct drm_i915
offset += page << PAGE_SHIFT;
}
- vaddr = (void __force *)io_mapping_map_atomic_wc(&ggtt->iomap,
- offset);
+ vaddr = (void __force *)io_mapping_map_local_wc(&ggtt->iomap, offset);
cache->page = page;
cache->vaddr = (unsigned long)vaddr;
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -379,22 +379,15 @@ gtt_user_read(struct io_mapping *mapping
char __user *user_data, int length)
{
void __iomem *vaddr;
- unsigned long unwritten;
+ bool fail = false;
/* We can use the cpu mem copy function because this is X86. */
- vaddr = io_mapping_map_atomic_wc(mapping, base);
- unwritten = __copy_to_user_inatomic(user_data,
- (void __force *)vaddr + offset,
- length);
- io_mapping_unmap_atomic(vaddr);
- if (unwritten) {
- vaddr = io_mapping_map_wc(mapping, base, PAGE_SIZE);
- unwritten = copy_to_user(user_data,
- (void __force *)vaddr + offset,
- length);
- io_mapping_unmap(vaddr);
- }
- return unwritten;
+ vaddr = io_mapping_map_local_wc(mapping, base);
+ if (copy_to_user(user_data, (void __force *)vaddr + offset, length))
+ fail = true;
+ io_mapping_unmap_local(vaddr);
+
+ return fail;
}
static int
@@ -557,21 +550,14 @@ ggtt_write(struct io_mapping *mapping,
char __user *user_data, int length)
{
void __iomem *vaddr;
- unsigned long unwritten;
+ bool fail = false;
/* We can use the cpu mem copy function because this is X86. */
- vaddr = io_mapping_map_atomic_wc(mapping, base);
- unwritten = __copy_from_user_inatomic_nocache((void __force *)vaddr + offset,
- user_data, length);
- io_mapping_unmap_atomic(vaddr);
- if (unwritten) {
- vaddr = io_mapping_map_wc(mapping, base, PAGE_SIZE);
- unwritten = copy_from_user((void __force *)vaddr + offset,
- user_data, length);
- io_mapping_unmap(vaddr);
- }
-
- return unwritten;
+ vaddr = io_mapping_map_local_wc(mapping, base);
+ if (copy_from_user((void __force *)vaddr + offset, user_data, length))
+ fail = true;
+ io_mapping_unmap_local(vaddr);
+ return fail;
}
/**
--- a/drivers/gpu/drm/i915/selftests/i915_gem.c
+++ b/drivers/gpu/drm/i915/selftests/i915_gem.c
@@ -57,12 +57,12 @@ static void trash_stolen(struct drm_i915
ggtt->vm.insert_page(&ggtt->vm, dma, slot, I915_CACHE_NONE, 0);
- s = io_mapping_map_atomic_wc(&ggtt->iomap, slot);
+ s = io_mapping_map_local_wc(&ggtt->iomap, slot);
for (x = 0; x < PAGE_SIZE / sizeof(u32); x++) {
prng = next_pseudo_random32(prng);
iowrite32(prng, &s[x]);
}
- io_mapping_unmap_atomic(s);
+ io_mapping_unmap_local(s);
}
ggtt->vm.clear_range(&ggtt->vm, slot, PAGE_SIZE);
--- a/drivers/gpu/drm/i915/selftests/i915_gem_gtt.c
+++ b/drivers/gpu/drm/i915/selftests/i915_gem_gtt.c
@@ -1200,9 +1200,9 @@ static int igt_ggtt_page(void *arg)
u64 offset = tmp.start + order[n] * PAGE_SIZE;
u32 __iomem *vaddr;
- vaddr = io_mapping_map_atomic_wc(&ggtt->iomap, offset);
+ vaddr = io_mapping_map_local_wc(&ggtt->iomap, offset);
iowrite32(n, vaddr + n);
- io_mapping_unmap_atomic(vaddr);
+ io_mapping_unmap_local(vaddr);
}
intel_gt_flush_ggtt_writes(ggtt->vm.gt);
@@ -1212,9 +1212,9 @@ static int igt_ggtt_page(void *arg)
u32 __iomem *vaddr;
u32 val;
- vaddr = io_mapping_map_atomic_wc(&ggtt->iomap, offset);
+ vaddr = io_mapping_map_local_wc(&ggtt->iomap, offset);
val = ioread32(vaddr + n);
- io_mapping_unmap_atomic(vaddr);
+ io_mapping_unmap_local(vaddr);
if (val != n) {
pr_err("insert page failed: found %d, expected %d\n",
^ permalink raw reply
* [patch V3 35/37] drm/nouveau/device: Replace io_mapping_map_atomic_wc()
From: Thomas Gleixner @ 2020-11-03 9:27 UTC (permalink / raw)
To: LKML
Cc: Juri Lelli, linux-aio, Peter Zijlstra, nouveau,
Sebastian Andrzej Siewior, Joonas Lahtinen, dri-devel,
virtualization, Ben Segall, linux-mm, Huang Rui, Paul Mackerras,
Gerd Hoffmann, Daniel Bristot de Oliveira, sparclinux,
Vincent Chen, Christoph Hellwig, Vincent Guittot, Arnd Bergmann,
Max Filippov, x86, Russell King, linux-csky, Ingo Molnar,
David Airlie, VMware Graphics, Ben Skeggs, Dave Airlie,
linux-snps-arc, Mel Gorman, linux-xtensa, Paul McKenney,
intel-gfx, Roland Scheidegger, Josef Bacik, Steven Rostedt,
Linus Torvalds, Alexander Viro, spice-devel, David Sterba,
Rodrigo Vivi, Dietmar Eggemann, linux-arm-kernel, Jani Nikula,
Chris Zankel, Michal Simek, Thomas Bogendoerfer, Nick Hu,
Chris Mason, Vineet Gupta, linux-mips, Christian Koenig,
Benjamin LaHaise, Daniel Vetter, linux-fsdevel, Andrew Morton,
linuxppc-dev, David S. Miller, linux-btrfs, Greentime Hu
In-Reply-To: <20201103092712.714480842@linutronix.de>
Neither fbmem_peek() nor fbmem_poke() require to disable pagefaults and
preemption as a side effect of io_mapping_map_atomic_wc().
Use io_mapping_map_local_wc() instead.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Ben Skeggs <bskeggs@redhat.com>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: dri-devel@lists.freedesktop.org
Cc: nouveau@lists.freedesktop.org
---
V3: New patch
---
drivers/gpu/drm/nouveau/nvkm/subdev/devinit/fbmem.h | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)
--- a/drivers/gpu/drm/nouveau/nvkm/subdev/devinit/fbmem.h
+++ b/drivers/gpu/drm/nouveau/nvkm/subdev/devinit/fbmem.h
@@ -60,19 +60,19 @@ fbmem_fini(struct io_mapping *fb)
static inline u32
fbmem_peek(struct io_mapping *fb, u32 off)
{
- u8 __iomem *p = io_mapping_map_atomic_wc(fb, off & PAGE_MASK);
+ u8 __iomem *p = io_mapping_map_local_wc(fb, off & PAGE_MASK);
u32 val = ioread32(p + (off & ~PAGE_MASK));
- io_mapping_unmap_atomic(p);
+ io_mapping_unmap_local(p);
return val;
}
static inline void
fbmem_poke(struct io_mapping *fb, u32 off, u32 val)
{
- u8 __iomem *p = io_mapping_map_atomic_wc(fb, off & PAGE_MASK);
+ u8 __iomem *p = io_mapping_map_local_wc(fb, off & PAGE_MASK);
iowrite32(val, p + (off & ~PAGE_MASK));
wmb();
- io_mapping_unmap_atomic(p);
+ io_mapping_unmap_local(p);
}
static inline bool
^ permalink raw reply
* [patch V3 34/37] drm/qxl: Replace io_mapping_map_atomic_wc()
From: Thomas Gleixner @ 2020-11-03 9:27 UTC (permalink / raw)
To: LKML
Cc: Juri Lelli, linux-aio, Peter Zijlstra, Sebastian Andrzej Siewior,
Joonas Lahtinen, dri-devel, virtualization, Ben Segall, linux-mm,
Huang Rui, Paul Mackerras, Gerd Hoffmann,
Daniel Bristot de Oliveira, sparclinux, Vincent Chen,
Christoph Hellwig, Vincent Guittot, Arnd Bergmann, Max Filippov,
x86, Russell King, linux-csky, Ingo Molnar, David Airlie,
VMware Graphics, Mel Gorman, nouveau, spice-devel, linux-snps-arc,
Ben Skeggs, linux-xtensa, Paul McKenney, intel-gfx,
Roland Scheidegger, Josef Bacik, Steven Rostedt, Linus Torvalds,
Alexander Viro, Dave Airlie, David Sterba, Rodrigo Vivi,
Dietmar Eggemann, linux-arm-kernel, Jani Nikula, Chris Zankel,
Michal Simek, Thomas Bogendoerfer, Nick Hu, Chris Mason,
Vineet Gupta, linux-mips, Christian Koenig, Benjamin LaHaise,
Daniel Vetter, linux-fsdevel, Andrew Morton, linuxppc-dev,
David S. Miller, linux-btrfs, Greentime Hu
In-Reply-To: <20201103092712.714480842@linutronix.de>
None of these mapping requires the side effect of disabling pagefaults and
preemption.
Use io_mapping_map_local_wc() instead, rename the related functions
accordingly and clean up qxl_process_single_command() to use a plain
copy_from_user() as the local maps are not disabling pagefaults.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Dave Airlie <airlied@redhat.com>
Cc: Gerd Hoffmann <kraxel@redhat.com>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: virtualization@lists.linux-foundation.org
Cc: spice-devel@lists.freedesktop.org
---
V3: New patch
---
drivers/gpu/drm/qxl/qxl_image.c | 18 +++++++++---------
drivers/gpu/drm/qxl/qxl_ioctl.c | 27 +++++++++++++--------------
drivers/gpu/drm/qxl/qxl_object.c | 12 ++++++------
drivers/gpu/drm/qxl/qxl_object.h | 4 ++--
drivers/gpu/drm/qxl/qxl_release.c | 4 ++--
5 files changed, 32 insertions(+), 33 deletions(-)
--- a/drivers/gpu/drm/qxl/qxl_image.c
+++ b/drivers/gpu/drm/qxl/qxl_image.c
@@ -124,12 +124,12 @@ qxl_image_init_helper(struct qxl_device
wrong (check the bitmaps are sent correctly
first) */
- ptr = qxl_bo_kmap_atomic_page(qdev, chunk_bo, 0);
+ ptr = qxl_bo_kmap_local_page(qdev, chunk_bo, 0);
chunk = ptr;
chunk->data_size = height * chunk_stride;
chunk->prev_chunk = 0;
chunk->next_chunk = 0;
- qxl_bo_kunmap_atomic_page(qdev, chunk_bo, ptr);
+ qxl_bo_kunmap_local_page(qdev, chunk_bo, ptr);
{
void *k_data, *i_data;
@@ -143,7 +143,7 @@ qxl_image_init_helper(struct qxl_device
i_data = (void *)data;
while (remain > 0) {
- ptr = qxl_bo_kmap_atomic_page(qdev, chunk_bo, page << PAGE_SHIFT);
+ ptr = qxl_bo_kmap_local_page(qdev, chunk_bo, page << PAGE_SHIFT);
if (page == 0) {
chunk = ptr;
@@ -157,7 +157,7 @@ qxl_image_init_helper(struct qxl_device
memcpy(k_data, i_data, size);
- qxl_bo_kunmap_atomic_page(qdev, chunk_bo, ptr);
+ qxl_bo_kunmap_local_page(qdev, chunk_bo, ptr);
i_data += size;
remain -= size;
page++;
@@ -175,10 +175,10 @@ qxl_image_init_helper(struct qxl_device
page_offset = offset_in_page(out_offset);
size = min((int)(PAGE_SIZE - page_offset), remain);
- ptr = qxl_bo_kmap_atomic_page(qdev, chunk_bo, page_base);
+ ptr = qxl_bo_kmap_local_page(qdev, chunk_bo, page_base);
k_data = ptr + page_offset;
memcpy(k_data, i_data, size);
- qxl_bo_kunmap_atomic_page(qdev, chunk_bo, ptr);
+ qxl_bo_kunmap_local_page(qdev, chunk_bo, ptr);
remain -= size;
i_data += size;
out_offset += size;
@@ -189,7 +189,7 @@ qxl_image_init_helper(struct qxl_device
qxl_bo_kunmap(chunk_bo);
image_bo = dimage->bo;
- ptr = qxl_bo_kmap_atomic_page(qdev, image_bo, 0);
+ ptr = qxl_bo_kmap_local_page(qdev, image_bo, 0);
image = ptr;
image->descriptor.id = 0;
@@ -212,7 +212,7 @@ qxl_image_init_helper(struct qxl_device
break;
default:
DRM_ERROR("unsupported image bit depth\n");
- qxl_bo_kunmap_atomic_page(qdev, image_bo, ptr);
+ qxl_bo_kunmap_local_page(qdev, image_bo, ptr);
return -EINVAL;
}
image->u.bitmap.flags = QXL_BITMAP_TOP_DOWN;
@@ -222,7 +222,7 @@ qxl_image_init_helper(struct qxl_device
image->u.bitmap.palette = 0;
image->u.bitmap.data = qxl_bo_physical_address(qdev, chunk_bo, 0);
- qxl_bo_kunmap_atomic_page(qdev, image_bo, ptr);
+ qxl_bo_kunmap_local_page(qdev, image_bo, ptr);
return 0;
}
--- a/drivers/gpu/drm/qxl/qxl_ioctl.c
+++ b/drivers/gpu/drm/qxl/qxl_ioctl.c
@@ -89,11 +89,11 @@ apply_reloc(struct qxl_device *qdev, str
{
void *reloc_page;
- reloc_page = qxl_bo_kmap_atomic_page(qdev, info->dst_bo, info->dst_offset & PAGE_MASK);
+ reloc_page = qxl_bo_kmap_local_page(qdev, info->dst_bo, info->dst_offset & PAGE_MASK);
*(uint64_t *)(reloc_page + (info->dst_offset & ~PAGE_MASK)) = qxl_bo_physical_address(qdev,
info->src_bo,
info->src_offset);
- qxl_bo_kunmap_atomic_page(qdev, info->dst_bo, reloc_page);
+ qxl_bo_kunmap_local_page(qdev, info->dst_bo, reloc_page);
}
static void
@@ -105,9 +105,9 @@ apply_surf_reloc(struct qxl_device *qdev
if (info->src_bo && !info->src_bo->is_primary)
id = info->src_bo->surface_id;
- reloc_page = qxl_bo_kmap_atomic_page(qdev, info->dst_bo, info->dst_offset & PAGE_MASK);
+ reloc_page = qxl_bo_kmap_local_page(qdev, info->dst_bo, info->dst_offset & PAGE_MASK);
*(uint32_t *)(reloc_page + (info->dst_offset & ~PAGE_MASK)) = id;
- qxl_bo_kunmap_atomic_page(qdev, info->dst_bo, reloc_page);
+ qxl_bo_kunmap_local_page(qdev, info->dst_bo, reloc_page);
}
/* return holding the reference to this object */
@@ -149,7 +149,6 @@ static int qxl_process_single_command(st
struct qxl_bo *cmd_bo;
void *fb_cmd;
int i, ret, num_relocs;
- int unwritten;
switch (cmd->type) {
case QXL_CMD_DRAW:
@@ -185,21 +184,21 @@ static int qxl_process_single_command(st
goto out_free_reloc;
/* TODO copy slow path code from i915 */
- fb_cmd = qxl_bo_kmap_atomic_page(qdev, cmd_bo, (release->release_offset & PAGE_MASK));
- unwritten = __copy_from_user_inatomic_nocache
- (fb_cmd + sizeof(union qxl_release_info) + (release->release_offset & ~PAGE_MASK),
- u64_to_user_ptr(cmd->command), cmd->command_size);
+ fb_cmd = qxl_bo_kmap_local_page(qdev, cmd_bo, (release->release_offset & PAGE_MASK));
- {
+ if (copy_from_user(fb_cmd + sizeof(union qxl_release_info) +
+ (release->release_offset & ~PAGE_MASK),
+ u64_to_user_ptr(cmd->command), cmd->command_size)) {
+ ret = -EFAULT;
+ } else {
struct qxl_drawable *draw = fb_cmd;
draw->mm_time = qdev->rom->mm_clock;
}
- qxl_bo_kunmap_atomic_page(qdev, cmd_bo, fb_cmd);
- if (unwritten) {
- DRM_ERROR("got unwritten %d\n", unwritten);
- ret = -EFAULT;
+ qxl_bo_kunmap_local_page(qdev, cmd_bo, fb_cmd);
+ if (ret) {
+ DRM_ERROR("copy from user failed %d\n", ret);
goto out_free_release;
}
--- a/drivers/gpu/drm/qxl/qxl_object.c
+++ b/drivers/gpu/drm/qxl/qxl_object.c
@@ -172,8 +172,8 @@ int qxl_bo_kmap(struct qxl_bo *bo, void
return 0;
}
-void *qxl_bo_kmap_atomic_page(struct qxl_device *qdev,
- struct qxl_bo *bo, int page_offset)
+void *qxl_bo_kmap_local_page(struct qxl_device *qdev,
+ struct qxl_bo *bo, int page_offset)
{
unsigned long offset;
void *rptr;
@@ -188,7 +188,7 @@ void *qxl_bo_kmap_atomic_page(struct qxl
goto fallback;
offset = bo->tbo.mem.start << PAGE_SHIFT;
- return io_mapping_map_atomic_wc(map, offset + page_offset);
+ return io_mapping_map_local_wc(map, offset + page_offset);
fallback:
if (bo->kptr) {
rptr = bo->kptr + (page_offset * PAGE_SIZE);
@@ -214,14 +214,14 @@ void qxl_bo_kunmap(struct qxl_bo *bo)
ttm_bo_kunmap(&bo->kmap);
}
-void qxl_bo_kunmap_atomic_page(struct qxl_device *qdev,
- struct qxl_bo *bo, void *pmap)
+void qxl_bo_kunmap_local_page(struct qxl_device *qdev,
+ struct qxl_bo *bo, void *pmap)
{
if ((bo->tbo.mem.mem_type != TTM_PL_VRAM) &&
(bo->tbo.mem.mem_type != TTM_PL_PRIV))
goto fallback;
- io_mapping_unmap_atomic(pmap);
+ io_mapping_unmap_local(pmap);
return;
fallback:
qxl_bo_kunmap(bo);
--- a/drivers/gpu/drm/qxl/qxl_object.h
+++ b/drivers/gpu/drm/qxl/qxl_object.h
@@ -88,8 +88,8 @@ extern int qxl_bo_create(struct qxl_devi
struct qxl_bo **bo_ptr);
extern int qxl_bo_kmap(struct qxl_bo *bo, void **ptr);
extern void qxl_bo_kunmap(struct qxl_bo *bo);
-void *qxl_bo_kmap_atomic_page(struct qxl_device *qdev, struct qxl_bo *bo, int page_offset);
-void qxl_bo_kunmap_atomic_page(struct qxl_device *qdev, struct qxl_bo *bo, void *map);
+void *qxl_bo_kmap_local_page(struct qxl_device *qdev, struct qxl_bo *bo, int page_offset);
+void qxl_bo_kunmap_local_page(struct qxl_device *qdev, struct qxl_bo *bo, void *map);
extern struct qxl_bo *qxl_bo_ref(struct qxl_bo *bo);
extern void qxl_bo_unref(struct qxl_bo **bo);
extern int qxl_bo_pin(struct qxl_bo *bo);
--- a/drivers/gpu/drm/qxl/qxl_release.c
+++ b/drivers/gpu/drm/qxl/qxl_release.c
@@ -408,7 +408,7 @@ union qxl_release_info *qxl_release_map(
union qxl_release_info *info;
struct qxl_bo *bo = release->release_bo;
- ptr = qxl_bo_kmap_atomic_page(qdev, bo, release->release_offset & PAGE_MASK);
+ ptr = qxl_bo_kmap_local_page(qdev, bo, release->release_offset & PAGE_MASK);
if (!ptr)
return NULL;
info = ptr + (release->release_offset & ~PAGE_MASK);
@@ -423,7 +423,7 @@ void qxl_release_unmap(struct qxl_device
void *ptr;
ptr = ((void *)info) - (release->release_offset & ~PAGE_MASK);
- qxl_bo_kunmap_atomic_page(qdev, bo, ptr);
+ qxl_bo_kunmap_local_page(qdev, bo, ptr);
}
void qxl_release_fence_buffer_objects(struct qxl_release *release)
^ permalink raw reply
* [patch V3 32/37] drm/vmgfx: Replace kmap_atomic()
From: Thomas Gleixner @ 2020-11-03 9:27 UTC (permalink / raw)
To: LKML
Cc: Juri Lelli, linux-aio, Peter Zijlstra, Sebastian Andrzej Siewior,
Joonas Lahtinen, dri-devel, virtualization, Ben Segall, linux-mm,
Huang Rui, Paul Mackerras, Gerd Hoffmann,
Daniel Bristot de Oliveira, sparclinux, Vincent Chen,
Christoph Hellwig, Vincent Guittot, Arnd Bergmann, Max Filippov,
x86, Russell King, linux-csky, Ingo Molnar, David Airlie,
VMware Graphics, Mel Gorman, nouveau, Dave Airlie, linux-snps-arc,
Ben Skeggs, linux-xtensa, Paul McKenney, intel-gfx,
Roland Scheidegger, Josef Bacik, Steven Rostedt, Linus Torvalds,
Alexander Viro, spice-devel, David Sterba, Rodrigo Vivi,
Dietmar Eggemann, linux-arm-kernel, Jani Nikula, Chris Zankel,
Michal Simek, Thomas Bogendoerfer, Nick Hu, Chris Mason,
Vineet Gupta, linux-mips, Christian Koenig, Benjamin LaHaise,
Daniel Vetter, linux-fsdevel, Andrew Morton, linuxppc-dev,
David S. Miller, linux-btrfs, Greentime Hu
In-Reply-To: <20201103092712.714480842@linutronix.de>
There is no reason to disable pagefaults and preemption as a side effect of
kmap_atomic_prot().
Use kmap_local_page_prot() instead and document the reasoning for the
mapping usage with the given pgprot.
Remove the NULL pointer check for the map. These functions return a valid
address for valid pages and the return was bogus anyway as it would have
left preemption and pagefaults disabled.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: VMware Graphics <linux-graphics-maintainer@vmware.com>
Cc: Roland Scheidegger <sroland@vmware.com>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: dri-devel@lists.freedesktop.org
---
V3: New patch
---
drivers/gpu/drm/vmwgfx/vmwgfx_blit.c | 30 ++++++++++++------------------
1 file changed, 12 insertions(+), 18 deletions(-)
--- a/drivers/gpu/drm/vmwgfx/vmwgfx_blit.c
+++ b/drivers/gpu/drm/vmwgfx/vmwgfx_blit.c
@@ -375,12 +375,12 @@ static int vmw_bo_cpu_blit_line(struct v
copy_size = min_t(u32, copy_size, PAGE_SIZE - src_page_offset);
if (unmap_src) {
- kunmap_atomic(d->src_addr);
+ kunmap_local(d->src_addr);
d->src_addr = NULL;
}
if (unmap_dst) {
- kunmap_atomic(d->dst_addr);
+ kunmap_local(d->dst_addr);
d->dst_addr = NULL;
}
@@ -388,12 +388,8 @@ static int vmw_bo_cpu_blit_line(struct v
if (WARN_ON_ONCE(dst_page >= d->dst_num_pages))
return -EINVAL;
- d->dst_addr =
- kmap_atomic_prot(d->dst_pages[dst_page],
- d->dst_prot);
- if (!d->dst_addr)
- return -ENOMEM;
-
+ d->dst_addr = kmap_local_page_prot(d->dst_pages[dst_page],
+ d->dst_prot);
d->mapped_dst = dst_page;
}
@@ -401,12 +397,8 @@ static int vmw_bo_cpu_blit_line(struct v
if (WARN_ON_ONCE(src_page >= d->src_num_pages))
return -EINVAL;
- d->src_addr =
- kmap_atomic_prot(d->src_pages[src_page],
- d->src_prot);
- if (!d->src_addr)
- return -ENOMEM;
-
+ d->src_addr = kmap_local_page_prot(d->src_pages[src_page],
+ d->src_prot);
d->mapped_src = src_page;
}
diff->do_cpy(diff, d->dst_addr + dst_page_offset,
@@ -436,8 +428,10 @@ static int vmw_bo_cpu_blit_line(struct v
*
* Performs a CPU blit from one buffer object to another avoiding a full
* bo vmap which may exhaust- or fragment vmalloc space.
- * On supported architectures (x86), we're using kmap_atomic which avoids
- * cross-processor TLB- and cache flushes and may, on non-HIGHMEM systems
+ *
+ * On supported architectures (x86), we're using kmap_local_prot() which
+ * avoids cross-processor TLB- and cache flushes. kmap_local_prot() will
+ * either map a highmem page with the proper pgprot on HIGHMEM=y systems or
* reference already set-up mappings.
*
* Neither of the buffer objects may be placed in PCI memory
@@ -500,9 +494,9 @@ int vmw_bo_cpu_blit(struct ttm_buffer_ob
}
out:
if (d.src_addr)
- kunmap_atomic(d.src_addr);
+ kunmap_local(d.src_addr);
if (d.dst_addr)
- kunmap_atomic(d.dst_addr);
+ kunmap_local(d.dst_addr);
return ret;
}
^ permalink raw reply
* [patch V3 33/37] highmem: Remove kmap_atomic_prot()
From: Thomas Gleixner @ 2020-11-03 9:27 UTC (permalink / raw)
To: LKML
Cc: Juri Lelli, linux-aio, Peter Zijlstra, Sebastian Andrzej Siewior,
Joonas Lahtinen, dri-devel, virtualization, Ben Segall,
Chris Mason, Huang Rui, Paul Mackerras, Gerd Hoffmann,
Daniel Bristot de Oliveira, sparclinux, Vincent Chen,
Christoph Hellwig, Vincent Guittot, Paul McKenney, Max Filippov,
x86, Russell King, linux-csky, Ingo Molnar, David Airlie,
VMware Graphics, Mel Gorman, nouveau, Dave Airlie, linux-snps-arc,
Ben Skeggs, linux-xtensa, Arnd Bergmann, intel-gfx,
Roland Scheidegger, Josef Bacik, Steven Rostedt, Linus Torvalds,
Alexander Viro, spice-devel, David Sterba, Rodrigo Vivi,
Dietmar Eggemann, linux-arm-kernel, Jani Nikula, Chris Zankel,
Michal Simek, Thomas Bogendoerfer, Nick Hu, linux-mm,
Vineet Gupta, linux-mips, Christian Koenig, Benjamin LaHaise,
Daniel Vetter, linux-fsdevel, Andrew Morton, linuxppc-dev,
David S. Miller, linux-btrfs, Greentime Hu
In-Reply-To: <20201103092712.714480842@linutronix.de>
No more users.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---
V3: New patch
---
include/linux/highmem-internal.h | 14 ++------------
1 file changed, 2 insertions(+), 12 deletions(-)
--- a/include/linux/highmem-internal.h
+++ b/include/linux/highmem-internal.h
@@ -87,16 +87,11 @@ static inline void __kunmap_local(void *
kunmap_local_indexed(vaddr);
}
-static inline void *kmap_atomic_prot(struct page *page, pgprot_t prot)
+static inline void *kmap_atomic(struct page *page)
{
preempt_disable();
pagefault_disable();
- return __kmap_local_page_prot(page, prot);
-}
-
-static inline void *kmap_atomic(struct page *page)
-{
- return kmap_atomic_prot(page, kmap_prot);
+ return __kmap_local_page_prot(page, kmap_prot);
}
static inline void __kunmap_atomic(void *addr)
@@ -181,11 +176,6 @@ static inline void *kmap_atomic(struct p
return page_address(page);
}
-static inline void *kmap_atomic_prot(struct page *page, pgprot_t prot)
-{
- return kmap_atomic(page);
-}
-
static inline void __kunmap_atomic(void *addr)
{
#ifdef ARCH_HAS_FLUSH_ON_KUNMAP
^ permalink raw reply
* [patch V3 31/37] drm/ttm: Replace kmap_atomic() usage
From: Thomas Gleixner @ 2020-11-03 9:27 UTC (permalink / raw)
To: LKML
Cc: Juri Lelli, linux-aio, Peter Zijlstra, Sebastian Andrzej Siewior,
Joonas Lahtinen, dri-devel, virtualization, Ben Segall, linux-mm,
Huang Rui, Paul Mackerras, Gerd Hoffmann,
Daniel Bristot de Oliveira, sparclinux, Vincent Chen,
Christoph Hellwig, Vincent Guittot, Arnd Bergmann, Max Filippov,
x86, Russell King, linux-csky, Ingo Molnar, David Airlie,
VMware Graphics, Mel Gorman, nouveau, Dave Airlie, linux-snps-arc,
Ben Skeggs, linux-xtensa, Paul McKenney, intel-gfx,
Roland Scheidegger, Josef Bacik, Steven Rostedt, Linus Torvalds,
Alexander Viro, spice-devel, David Sterba, Rodrigo Vivi,
Dietmar Eggemann, linux-arm-kernel, Jani Nikula, Chris Zankel,
Michal Simek, Thomas Bogendoerfer, Nick Hu, Chris Mason,
Vineet Gupta, linux-mips, David S. Miller, Benjamin LaHaise,
Daniel Vetter, linux-fsdevel, Andrew Morton, linuxppc-dev,
Christian Koenig, linux-btrfs, Greentime Hu
In-Reply-To: <20201103092712.714480842@linutronix.de>
There is no reason to disable pagefaults and preemption as a side effect of
kmap_atomic_prot().
Use kmap_local_page_prot() instead and document the reasoning for the
mapping usage with the given pgprot.
Remove the NULL pointer check for the map. These functions return a valid
address for valid pages and the return was bogus anyway as it would have
left preemption and pagefaults disabled.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Christian Koenig <christian.koenig@amd.com>
Cc: Huang Rui <ray.huang@amd.com>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: dri-devel@lists.freedesktop.org
---
V3: New patch
---
drivers/gpu/drm/ttm/ttm_bo_util.c | 20 ++++++++++++--------
1 file changed, 12 insertions(+), 8 deletions(-)
--- a/drivers/gpu/drm/ttm/ttm_bo_util.c
+++ b/drivers/gpu/drm/ttm/ttm_bo_util.c
@@ -181,13 +181,15 @@ static int ttm_copy_io_ttm_page(struct t
return -ENOMEM;
src = (void *)((unsigned long)src + (page << PAGE_SHIFT));
- dst = kmap_atomic_prot(d, prot);
- if (!dst)
- return -ENOMEM;
+ /*
+ * Ensure that a highmem page is mapped with the correct
+ * pgprot. For non highmem the mapping is already there.
+ */
+ dst = kmap_local_page_prot(d, prot);
memcpy_fromio(dst, src, PAGE_SIZE);
- kunmap_atomic(dst);
+ kunmap_local(dst);
return 0;
}
@@ -203,13 +205,15 @@ static int ttm_copy_ttm_io_page(struct t
return -ENOMEM;
dst = (void *)((unsigned long)dst + (page << PAGE_SHIFT));
- src = kmap_atomic_prot(s, prot);
- if (!src)
- return -ENOMEM;
+ /*
+ * Ensure that a highmem page is mapped with the correct
+ * pgprot. For non highmem the mapping is already there.
+ */
+ src = kmap_local_page_prot(s, prot);
memcpy_toio(dst, src, PAGE_SIZE);
- kunmap_atomic(src);
+ kunmap_local(src);
return 0;
}
^ permalink raw reply
* [patch V3 30/37] highmem: Remove kmap_atomic_pfn()
From: Thomas Gleixner @ 2020-11-03 9:27 UTC (permalink / raw)
To: LKML
Cc: Juri Lelli, linux-aio, Peter Zijlstra, Sebastian Andrzej Siewior,
Joonas Lahtinen, dri-devel, virtualization, Ben Segall,
Chris Mason, Huang Rui, Paul Mackerras, Gerd Hoffmann,
Daniel Bristot de Oliveira, sparclinux, Vincent Chen,
Christoph Hellwig, Vincent Guittot, Paul McKenney, Max Filippov,
x86, Russell King, linux-csky, Ingo Molnar, David Airlie,
VMware Graphics, Mel Gorman, nouveau, Dave Airlie, linux-snps-arc,
Ben Skeggs, linux-xtensa, Arnd Bergmann, intel-gfx,
Roland Scheidegger, Josef Bacik, Steven Rostedt, Linus Torvalds,
Alexander Viro, spice-devel, David Sterba, Rodrigo Vivi,
Dietmar Eggemann, linux-arm-kernel, Jani Nikula, Chris Zankel,
Michal Simek, Thomas Bogendoerfer, Nick Hu, linux-mm,
Vineet Gupta, linux-mips, Christian Koenig, Benjamin LaHaise,
Daniel Vetter, linux-fsdevel, Andrew Morton, linuxppc-dev,
David S. Miller, linux-btrfs, Greentime Hu
In-Reply-To: <20201103092712.714480842@linutronix.de>
No more users.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---
V3: New patch
---
include/linux/highmem-internal.h | 12 ------------
1 file changed, 12 deletions(-)
--- a/include/linux/highmem-internal.h
+++ b/include/linux/highmem-internal.h
@@ -99,13 +99,6 @@ static inline void *kmap_atomic(struct p
return kmap_atomic_prot(page, kmap_prot);
}
-static inline void *kmap_atomic_pfn(unsigned long pfn)
-{
- preempt_disable();
- pagefault_disable();
- return __kmap_local_pfn_prot(pfn, kmap_prot);
-}
-
static inline void __kunmap_atomic(void *addr)
{
kunmap_local_indexed(addr);
@@ -193,11 +186,6 @@ static inline void *kmap_atomic_prot(str
return kmap_atomic(page);
}
-static inline void *kmap_atomic_pfn(unsigned long pfn)
-{
- return kmap_atomic(pfn_to_page(pfn));
-}
-
static inline void __kunmap_atomic(void *addr)
{
#ifdef ARCH_HAS_FLUSH_ON_KUNMAP
^ permalink raw reply
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