* [PATCH v13 5/6] ndctl/papr_scm, uapi: Add support for PAPR nvdimm specific methods
From: Vaibhav Jain @ 2020-06-15 12:44 UTC (permalink / raw)
To: linuxppc-dev, linux-nvdimm, linux-kernel
Cc: Santosh Sivaraj, Steven Rostedt, Oliver O'Halloran,
Aneesh Kumar K . V, Vaibhav Jain, Dan Williams, Ira Weiny
In-Reply-To: <20200615124407.32596-1-vaibhav@linux.ibm.com>
Introduce support for PAPR NVDIMM Specific Methods (PDSM) in papr_scm
module and add the command family NVDIMM_FAMILY_PAPR to the white list
of NVDIMM command sets. Also advertise support for ND_CMD_CALL for the
nvdimm command mask and implement necessary scaffolding in the module
to handle ND_CMD_CALL ioctl and PDSM requests that we receive.
The layout of the PDSM request as we expect from libnvdimm/libndctl is
described in newly introduced uapi header 'papr_pdsm.h' which
defines a 'struct nd_pkg_pdsm' and a maximal union named
'nd_pdsm_payload'. These new structs together with 'struct nd_cmd_pkg'
for a pdsm envelop thats sent by libndctl to libnvdimm and serviced by
papr_scm in 'papr_scm_service_pdsm()'. The PDSM request is
communicated by member 'struct nd_cmd_pkg.nd_command' together with
other information on the pdsm payload (size-in, size-out).
The patch also introduces 'struct pdsm_cmd_desc' instances of which
are stored in an array __pdsm_cmd_descriptors[] indexed with PDSM cmd
and corresponding access function pdsm_cmd_desc() is
introduced. 'struct pdsm_cdm_desc' holds the service function for a
given PDSM and corresponding payload in/out sizes.
A new function papr_scm_service_pdsm() is introduced and is called from
papr_scm_ndctl() in case of a PDSM request is received via ND_CMD_CALL
command from libnvdimm. The function performs validation on the PDSM
payload based on info present in corresponding PDSM descriptor and if
valid calls the 'struct pdcm_cmd_desc.service' function to service the
PDSM.
Cc: "Aneesh Kumar K . V" <aneesh.kumar@linux.ibm.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Vaibhav Jain <vaibhav@linux.ibm.com>
---
Changelog:
v12..v13:
* s/struct nd_pdsm_cmd_pkg/struct nd_pkg_pdsm/
* Removed instance of 'struct nd_cmd_pkg hdr' from 'struct
nd_pdsm_cmd_pkg'.
* Introduced 'union nd_pdsm_payload' thats a maximal union of all
possible payload structs.
* Instead of having flexible 'payload' member 'struct nd_pdsm_cmd_pkg'
replace it with a 'union nd_pdsm_payload'.
* Introduce pdsm descriptor 'struct pdsm_cmd_desc' and its array
__pdsm_cmd_descriptors[] that holds a payload 'size_[in|out]' and
service function for each pdsm. This is analogus to
'__nd_cmd_dimm_descs[]'
* Introduce function 'pdsm_cmd_desc()' to fetch the corrosponding pdsm
descriptor for each valid pdsm.
* Updated papr_scm_service_pdsm() to use 'pdsm_cmd_desc()' and apply
checks on 'nd_cmd_pkg' payload based on psdm descriptor members and
finally service the pdsm using the 'service' member of the
descriptor.
* Updated 'papr_scm_ndctl()' to send the 'struct nd_cmd_pkg*' instance
to papr_scm_service_pdsm() instead of a 'struct nd_pdsm_cmd_pkg*'.
* Updated documentation in 'papr_psdm.h' to reflect new pdsm envelope
layout.
* Update patch description.
v11..v12:
* Updated a misleading comment in 'papr_pdsm.h' regarding payload
size. [ Ira ]
v10..v11:
* Moved in-lines 'nd_pdsm_cmd_pkg()' and 'pdsm_cmd_to_payload()' from
'papr_pdsm.h' header to 'papr_scm.c'. The avoids a potential license
incompatibility issue with non-GPL-2.0 user-space code trying to
include the header in its code. [ Ira ]
* Verified papr_pdsm.h with UAPI_HEADER_TEST config.
* Moved the is_cmd_valid() check in papr_scm_ndctl() before check for
cmd_rc == NULL. This prevents cmd_rc to be updated in case the
nd-cmd is invalid or unknown.
v9..v10:
* Simplified 'struct nd_pdsm_cmd_pkg' by removing the
'payload_version' field.
* Removed the corrosponding documentation on versioning and backward
compatibility from 'papr_pdsm.h'
* Reduced the size of reserved fields to 4-bytes making 'struct
nd_pdsm_cmd_pkg' 64 + 8 bytes long.
* Updated is_cmd_valid() to enforce validation checks on pdsm
commands. [ Dan Williams ]
* Added check for reserved fields being set to '0' in is_cmd_valid()
[ Ira ]
* Moved changes for checking cmd_rc == NULL and logging improvements
to a separate prelim patch [ Ira ].
* Moved pdsm package validation checks from papr_scm_service_pdsm()
to is_cmd_valid().
* Marked papr_scm_service_pdsm() return type as 'void' since errors
are reported in nd_pdsm_cmd_pkg.cmd_status field.
Resend:
* Added ack from Aneesh.
v8..v9:
* Reduced the usage of term SCM replacing it with appropriate
replacement [ Dan Williams, Aneesh ]
* Renamed 'papr_scm_pdsm.h' to 'papr_pdsm.h'
* s/PAPR_SCM_PDSM_*/PAPR_PDSM_*/g
* s/NVDIMM_FAMILY_PAPR_SCM/NVDIMM_FAMILY_PAPR/g
* Minor updates to 'papr_psdm.h' to replace usage of term 'SCM'.
* Minor update to patch description.
v7..v8:
* Removed the 'payload_offset' field from 'struct
nd_pdsm_cmd_pkg'. Instead command payload is always assumed to start
at 'nd_pdsm_cmd_pkg.payload'. [ Aneesh ]
* To enable introducing new fields to 'struct nd_pdsm_cmd_pkg',
'reserved' field of 10-bytes is introduced. [ Aneesh ]
* Fixed a typo in "Backward Compatibility" section of papr_scm_pdsm.h
[ Ira ]
Resend:
* None
v6..v7 :
* Removed the re-definitions of __packed macro from papr_scm_pdsm.h
[Mpe].
* Removed the usage of __KERNEL__ macros in papr_scm_pdsm.h [Mpe].
* Removed macros that were unused in papr_scm.c from papr_scm_pdsm.h
[Mpe].
* Made functions defined in papr_scm_pdsm.h as static inline. [Mpe]
v5..v6 :
* Changed the usage of the term DSM to PDSM to distinguish it from the
ACPI term [ Dan Williams ]
* Renamed papr_scm_dsm.h to papr_scm_pdsm.h and updated various struct
to reflect the new terminology.
* Updated the patch description and title to reflect the new terminology.
* Squashed patch to introduce new command family in 'ndctl.h' with
this patch [ Dan Williams ]
* Updated the papr_scm_pdsm method starting index from 0x10000 to 0x0
[ Dan Williams ]
* Removed redundant license text from the papr_scm_psdm.h file.
[ Dan Williams ]
* s/envelop/envelope/ at various places [ Dan Williams ]
* Added '__packed' attribute to command package header to gaurd
against different compiler adding paddings between the fields.
[ Dan Williams]
* Converted various pr_debug to dev_debug [ Dan Williams ]
v4..v5 :
* None
v3..v4 :
* None
v2..v3 :
* Updated the patch prefix to 'ndctl/uapi' [Aneesh]
v1..v2 :
* None
---
arch/powerpc/include/uapi/asm/papr_pdsm.h | 95 +++++++++++
arch/powerpc/platforms/pseries/papr_scm.c | 193 +++++++++++++++++++++-
include/uapi/linux/ndctl.h | 1 +
3 files changed, 285 insertions(+), 4 deletions(-)
create mode 100644 arch/powerpc/include/uapi/asm/papr_pdsm.h
diff --git a/arch/powerpc/include/uapi/asm/papr_pdsm.h b/arch/powerpc/include/uapi/asm/papr_pdsm.h
new file mode 100644
index 000000000000..28115152aa4e
--- /dev/null
+++ b/arch/powerpc/include/uapi/asm/papr_pdsm.h
@@ -0,0 +1,95 @@
+/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
+/*
+ * PAPR nvDimm Specific Methods (PDSM) and structs for libndctl
+ *
+ * (C) Copyright IBM 2020
+ *
+ * Author: Vaibhav Jain <vaibhav at linux.ibm.com>
+ */
+
+#ifndef _UAPI_ASM_POWERPC_PAPR_PDSM_H_
+#define _UAPI_ASM_POWERPC_PAPR_PDSM_H_
+
+#include <linux/types.h>
+#include <linux/ndctl.h>
+
+/*
+ * PDSM Envelope:
+ *
+ * The ioctl ND_CMD_CALL exchange data between user-space and kernel via
+ * envelope which consists of 2 headers sections and payload sections as
+ * illustrated below:
+ * +-----------------+---------------+---------------------------+
+ * | 64-Bytes | 8-Bytes | Max 184-Bytes |
+ * +-----------------+---------------+---------------------------+
+ * | ND-HEADER | PDSM-HEADER | PDSM-PAYLOAD |
+ * +-----------------+---------------+---------------------------+
+ * | nd_family | | |
+ * | nd_size_out | cmd_status | |
+ * | nd_size_in | reserved | nd_pdsm_payload |
+ * | nd_command | payload --> | |
+ * | nd_fw_size | | |
+ * | nd_payload ---> | | |
+ * +---------------+-----------------+---------------------------+
+ *
+ * ND Header:
+ * This is the generic libnvdimm header described as 'struct nd_cmd_pkg'
+ * which is interpreted by libnvdimm before passed on to papr_scm. Important
+ * member fields used are:
+ * 'nd_family' : (In) NVDIMM_FAMILY_PAPR_SCM
+ * 'nd_size_in' : (In) PDSM-HEADER + PDSM-IN-PAYLOAD (usually 0)
+ * 'nd_size_out' : (In) PDSM-HEADER + PDSM-RETURN-PAYLOAD
+ * 'nd_command' : (In) One of PAPR_PDSM_XXX
+ * 'nd_fw_size' : (Out) PDSM-HEADER + size of actual payload returned
+ *
+ * PDSM Header:
+ * This is papr-scm specific header that precedes the payload. This is defined
+ * as nd_cmd_pdsm_pkg. Following fields aare available in this header:
+ *
+ * 'cmd_status' : (Out) Errors if any encountered while servicing PDSM.
+ * 'reserved' : Not used, reserved for future and should be set to 0.
+ * 'payload' : A union of all the possible payload structs
+ *
+ * PDSM Payload:
+ *
+ * The layout of the PDSM Payload is defined by various structs shared between
+ * papr_scm and libndctl so that contents of payload can be interpreted. As such
+ * its defined as a union of all possible payload structs as
+ * 'union nd_pdsm_payload'. Based on the value of 'nd_cmd_pkg.nd_command'
+ * appropriate member of the union is accessed.
+ */
+
+/* Max payload size that we can handle */
+#define ND_PDSM_PAYLOAD_MAX_SIZE 184
+
+/* Max payload size that we can handle */
+#define ND_PDSM_HDR_SIZE \
+ (sizeof(struct nd_pkg_pdsm) - ND_PDSM_PAYLOAD_MAX_SIZE)
+
+/*
+ * Methods to be embedded in ND_CMD_CALL request. These are sent to the kernel
+ * via 'nd_cmd_pkg.nd_command' member of the ioctl struct
+ */
+enum papr_pdsm {
+ PAPR_PDSM_MIN = 0x0,
+ PAPR_PDSM_MAX,
+};
+
+/* Maximal union that can hold all possible payload types */
+union nd_pdsm_payload {
+ __u8 buf[ND_PDSM_PAYLOAD_MAX_SIZE];
+} __packed;
+
+/*
+ * PDSM-header + payload expected with ND_CMD_CALL ioctl from libnvdimm
+ * Valid member of union 'payload' is identified via 'nd_cmd_pkg.nd_command'
+ * that should always precede this struct when sent to papr_scm via CMD_CALL
+ * interface.
+ */
+struct nd_pkg_pdsm {
+ __s32 cmd_status; /* Out: Sub-cmd status returned back */
+ __u16 reserved[2]; /* Ignored and to be set as '0' */
+ union nd_pdsm_payload payload;
+} __packed;
+
+#endif /* _UAPI_ASM_POWERPC_PAPR_PDSM_H_ */
diff --git a/arch/powerpc/platforms/pseries/papr_scm.c b/arch/powerpc/platforms/pseries/papr_scm.c
index 692ad3d79826..d3bbf9940ba4 100644
--- a/arch/powerpc/platforms/pseries/papr_scm.c
+++ b/arch/powerpc/platforms/pseries/papr_scm.c
@@ -15,13 +15,15 @@
#include <linux/seq_buf.h>
#include <asm/plpar_wrappers.h>
+#include <asm/papr_pdsm.h>
#define BIND_ANY_ADDR (~0ul)
#define PAPR_SCM_DIMM_CMD_MASK \
((1ul << ND_CMD_GET_CONFIG_SIZE) | \
(1ul << ND_CMD_GET_CONFIG_DATA) | \
- (1ul << ND_CMD_SET_CONFIG_DATA))
+ (1ul << ND_CMD_SET_CONFIG_DATA) | \
+ (1ul << ND_CMD_CALL))
/* DIMM health bitmap bitmap indicators */
/* SCM device is unable to persist memory contents */
@@ -349,17 +351,195 @@ static int papr_scm_meta_set(struct papr_scm_priv *p,
return 0;
}
+/*
+ * Do a sanity checks on the inputs args to dimm-control function and return
+ * '0' if valid. Validation of PDSM payloads happens later in
+ * papr_scm_service_pdsm.
+ */
+static int is_cmd_valid(struct nvdimm *nvdimm, unsigned int cmd, void *buf,
+ unsigned int buf_len)
+{
+ unsigned long cmd_mask = PAPR_SCM_DIMM_CMD_MASK;
+ struct nd_cmd_pkg *nd_cmd;
+ struct papr_scm_priv *p;
+ enum papr_pdsm pdsm;
+
+ /* Only dimm-specific calls are supported atm */
+ if (!nvdimm)
+ return -EINVAL;
+
+ /* get the provider data from struct nvdimm */
+ p = nvdimm_provider_data(nvdimm);
+
+ if (!test_bit(cmd, &cmd_mask)) {
+ dev_dbg(&p->pdev->dev, "Unsupported cmd=%u\n", cmd);
+ return -EINVAL;
+ }
+
+ /* For CMD_CALL verify pdsm request */
+ if (cmd == ND_CMD_CALL) {
+ /* Verify the envelope and envelop size */
+ if (!buf ||
+ buf_len < (sizeof(struct nd_cmd_pkg) + ND_PDSM_HDR_SIZE)) {
+ dev_dbg(&p->pdev->dev, "Invalid pkg size=%u\n",
+ buf_len);
+ return -EINVAL;
+ }
+
+ /* Verify that the nd_cmd_pkg.nd_family is correct */
+ nd_cmd = (struct nd_cmd_pkg *)buf;
+
+ if (nd_cmd->nd_family != NVDIMM_FAMILY_PAPR) {
+ dev_dbg(&p->pdev->dev, "Invalid pkg family=0x%llx\n",
+ nd_cmd->nd_family);
+ return -EINVAL;
+ }
+
+ pdsm = (enum papr_pdsm)nd_cmd->nd_command;
+
+ /* Verify if the pdsm command is valid */
+ if (pdsm <= PAPR_PDSM_MIN || pdsm >= PAPR_PDSM_MAX) {
+ dev_dbg(&p->pdev->dev, "PDSM[0x%x]: Invalid PDSM\n",
+ pdsm);
+ return -EINVAL;
+ }
+
+ /* Have enough space to hold returned 'nd_pkg_pdsm' header */
+ if (nd_cmd->nd_size_out < ND_PDSM_HDR_SIZE) {
+ dev_dbg(&p->pdev->dev, "PDSM[0x%x]: Invalid payload\n",
+ pdsm);
+ return -EINVAL;
+ }
+ }
+
+ /* Let the command be further processed */
+ return 0;
+}
+
+/*
+ * 'struct pdsm_cmd_desc'
+ * Identifies supported PDSMs' expected length of in/out payloads
+ * and pdsm service function.
+ *
+ * size_in : Size of input payload if any in the PDSM request.
+ * size_out : Size of output payload if any in the PDSM request.
+ * service : Service function for the PDSM request. Return semantics:
+ * rc < 0 : Error servicing PDSM and rc indicates the error.
+ * rc >=0 : Serviced successfully and 'rc' indicate number of
+ * bytes written to payload.
+ */
+struct pdsm_cmd_desc {
+ u32 size_in;
+ u32 size_out;
+ int (*service)(struct papr_scm_priv *dimm,
+ union nd_pdsm_payload *payload);
+};
+
+/* Holds all supported PDSMs' command descriptors */
+static const struct pdsm_cmd_desc __pdsm_cmd_descriptors[] = {
+ [PAPR_PDSM_MIN] = {
+ .size_in = 0,
+ .size_out = 0,
+ .service = NULL,
+ },
+ /* New PDSM command descriptors to be added below */
+
+ /* Empty */
+ [PAPR_PDSM_MAX] = {
+ .size_in = 0,
+ .size_out = 0,
+ .service = NULL,
+ },
+};
+
+/* Given a valid pdsm cmd return its command descriptor else return NULL */
+static inline const struct pdsm_cmd_desc *pdsm_cmd_desc(enum papr_pdsm cmd)
+{
+ if (cmd >= 0 || cmd < ARRAY_SIZE(__pdsm_cmd_descriptors))
+ return &__pdsm_cmd_descriptors[cmd];
+
+ return NULL;
+}
+
+/*
+ * For a given pdsm request call an appropriate service function.
+ * Returns errors if any while handling the pdsm command package.
+ */
+static int papr_scm_service_pdsm(struct papr_scm_priv *p,
+ struct nd_cmd_pkg *pkg)
+{
+ /* Get the PDSM header and PDSM command */
+ struct nd_pkg_pdsm *pdsm_pkg = (struct nd_pkg_pdsm *)pkg->nd_payload;
+ enum papr_pdsm pdsm = (enum papr_pdsm)pkg->nd_command;
+ const struct pdsm_cmd_desc *pdsc;
+ int rc;
+
+ /* Fetch corresponding pdsm descriptor for validation and servicing */
+ pdsc = pdsm_cmd_desc(pdsm);
+
+ /* Validate pdsm descriptor */
+ /* Ensure that reserved fields are 0 */
+ if (pdsm_pkg->reserved[0] || pdsm_pkg->reserved[1]) {
+ dev_dbg(&p->pdev->dev, "PDSM[0x%x]: Invalid reserved field\n",
+ pdsm);
+ return -EINVAL;
+ }
+
+ /* If pdsm expects some input, then ensure that the size_in matches */
+ if (pdsc->size_in &&
+ pkg->nd_size_in != (pdsc->size_in + ND_PDSM_HDR_SIZE)) {
+ dev_dbg(&p->pdev->dev, "PDSM[0x%x]: Mismatched size_in=%d\n",
+ pdsm, pkg->nd_size_in);
+ return -EINVAL;
+ }
+
+ /* If pdsm wants to return data, then ensure that size_out matches */
+ if (pdsc->size_out &&
+ pkg->nd_size_out != (pdsc->size_out + ND_PDSM_HDR_SIZE)) {
+ dev_dbg(&p->pdev->dev, "PDSM[0x%x]: Mismatched size_out=%d\n",
+ pdsm, pkg->nd_size_out);
+ return -EINVAL;
+ }
+
+ /* Service the pdsm */
+ if (pdsc->service) {
+ dev_dbg(&p->pdev->dev, "PDSM[0x%x]: Servicing..\n", pdsm);
+
+ rc = pdsc->service(p, &pdsm_pkg->payload);
+
+ if (rc < 0) {
+ /* error encountered while servicing pdsm */
+ pdsm_pkg->cmd_status = rc;
+ pkg->nd_fw_size = ND_PDSM_HDR_SIZE;
+ } else {
+ /* pdsm serviced and 'rc' bytes written to payload */
+ pdsm_pkg->cmd_status = 0;
+ pkg->nd_fw_size = ND_PDSM_HDR_SIZE + rc;
+ }
+ } else {
+ dev_dbg(&p->pdev->dev, "PDSM[0x%x]: Unsupported PDSM request\n",
+ pdsm);
+ pdsm_pkg->cmd_status = -ENOENT;
+ pkg->nd_fw_size = ND_PDSM_HDR_SIZE;
+ }
+
+ return pdsm_pkg->cmd_status;
+}
+
static int papr_scm_ndctl(struct nvdimm_bus_descriptor *nd_desc,
struct nvdimm *nvdimm, unsigned int cmd, void *buf,
unsigned int buf_len, int *cmd_rc)
{
struct nd_cmd_get_config_size *get_size_hdr;
+ struct nd_cmd_pkg *call_pkg = NULL;
struct papr_scm_priv *p;
int rc;
- /* Only dimm-specific calls are supported atm */
- if (!nvdimm)
- return -EINVAL;
+ rc = is_cmd_valid(nvdimm, cmd, buf, buf_len);
+ if (rc) {
+ pr_debug("Invalid cmd=0x%x. Err=%d\n", cmd, rc);
+ return rc;
+ }
/* Use a local variable in case cmd_rc pointer is NULL */
if (!cmd_rc)
@@ -385,6 +565,11 @@ static int papr_scm_ndctl(struct nvdimm_bus_descriptor *nd_desc,
*cmd_rc = papr_scm_meta_set(p, buf);
break;
+ case ND_CMD_CALL:
+ call_pkg = (struct nd_cmd_pkg *)buf;
+ *cmd_rc = papr_scm_service_pdsm(p, call_pkg);
+ break;
+
default:
dev_dbg(&p->pdev->dev, "Unknown command = %d\n", cmd);
return -EINVAL;
diff --git a/include/uapi/linux/ndctl.h b/include/uapi/linux/ndctl.h
index de5d90212409..0e09dc5cec19 100644
--- a/include/uapi/linux/ndctl.h
+++ b/include/uapi/linux/ndctl.h
@@ -244,6 +244,7 @@ struct nd_cmd_pkg {
#define NVDIMM_FAMILY_HPE2 2
#define NVDIMM_FAMILY_MSFT 3
#define NVDIMM_FAMILY_HYPERV 4
+#define NVDIMM_FAMILY_PAPR 5
#define ND_IOCTL_CALL _IOWR(ND_IOCTL, ND_CMD_CALL,\
struct nd_cmd_pkg)
--
2.26.2
^ permalink raw reply related
* Re: [PATCH v12 1/6] powerpc: Document details on H_SCM_HEALTH hcall
From: Vaibhav Jain @ 2020-06-15 12:47 UTC (permalink / raw)
To: linuxppc-dev, linux-nvdimm, linux-kernel
Cc: Santosh Sivaraj, Aneesh Kumar K . V, Steven Rostedt,
Oliver O'Halloran, Dan Williams, Ira Weiny
In-Reply-To: <20200615122644.31887-2-vaibhav@linux.ibm.com>
This accidently got reposted. Please ignore.
Vaibhav Jain <vaibhav@linux.ibm.com> writes:
> Add documentation to 'papr_hcalls.rst' describing the bitmap flags
> that are returned from H_SCM_HEALTH hcall as per the PAPR-SCM
> specification.
>
> Cc: "Aneesh Kumar K . V" <aneesh.kumar@linux.ibm.com>
> Cc: Dan Williams <dan.j.williams@intel.com>
> Cc: Michael Ellerman <mpe@ellerman.id.au>
> Cc: Ira Weiny <ira.weiny@intel.com>
> Acked-by: Ira Weiny <ira.weiny@intel.com>
> Signed-off-by: Vaibhav Jain <vaibhav@linux.ibm.com>
> ---
> Changelog:
>
> v11..v12:
> * None
>
> v10..v11:
> * None
>
> v9..v10:
> * Added ack from Ira.
>
> Resend:
> * None
>
> v8..v9:
> * s/SCM/PMEM device. [ Dan Williams, Aneesh ]
>
> v7..v8:
> * Added a clarification on bit-ordering of Health Bitmap
>
> Resend:
> * None
>
> v6..v7:
> * None
>
> v5..v6:
> * New patch in the series
> ---
> Documentation/powerpc/papr_hcalls.rst | 46 ++++++++++++++++++++++++---
> 1 file changed, 42 insertions(+), 4 deletions(-)
>
> diff --git a/Documentation/powerpc/papr_hcalls.rst b/Documentation/powerpc/papr_hcalls.rst
> index 3493631a60f8..48fcf1255a33 100644
> --- a/Documentation/powerpc/papr_hcalls.rst
> +++ b/Documentation/powerpc/papr_hcalls.rst
> @@ -220,13 +220,51 @@ from the LPAR memory.
> **H_SCM_HEALTH**
>
> | Input: drcIndex
> -| Out: *health-bitmap, health-bit-valid-bitmap*
> +| Out: *health-bitmap (r4), health-bit-valid-bitmap (r5)*
> | Return Value: *H_Success, H_Parameter, H_Hardware*
>
> Given a DRC Index return the info on predictive failure and overall health of
> -the NVDIMM. The asserted bits in the health-bitmap indicate a single predictive
> -failure and health-bit-valid-bitmap indicate which bits in health-bitmap are
> -valid.
> +the PMEM device. The asserted bits in the health-bitmap indicate one or more states
> +(described in table below) of the PMEM device and health-bit-valid-bitmap indicate
> +which bits in health-bitmap are valid. The bits are reported in
> +reverse bit ordering for example a value of 0xC400000000000000
> +indicates bits 0, 1, and 5 are valid.
> +
> +Health Bitmap Flags:
> +
> ++------+-----------------------------------------------------------------------+
> +| Bit | Definition |
> ++======+=======================================================================+
> +| 00 | PMEM device is unable to persist memory contents. |
> +| | If the system is powered down, nothing will be saved. |
> ++------+-----------------------------------------------------------------------+
> +| 01 | PMEM device failed to persist memory contents. Either contents were |
> +| | not saved successfully on power down or were not restored properly on |
> +| | power up. |
> ++------+-----------------------------------------------------------------------+
> +| 02 | PMEM device contents are persisted from previous IPL. The data from |
> +| | the last boot were successfully restored. |
> ++------+-----------------------------------------------------------------------+
> +| 03 | PMEM device contents are not persisted from previous IPL. There was no|
> +| | data to restore from the last boot. |
> ++------+-----------------------------------------------------------------------+
> +| 04 | PMEM device memory life remaining is critically low |
> ++------+-----------------------------------------------------------------------+
> +| 05 | PMEM device will be garded off next IPL due to failure |
> ++------+-----------------------------------------------------------------------+
> +| 06 | PMEM device contents cannot persist due to current platform health |
> +| | status. A hardware failure may prevent data from being saved or |
> +| | restored. |
> ++------+-----------------------------------------------------------------------+
> +| 07 | PMEM device is unable to persist memory contents in certain conditions|
> ++------+-----------------------------------------------------------------------+
> +| 08 | PMEM device is encrypted |
> ++------+-----------------------------------------------------------------------+
> +| 09 | PMEM device has successfully completed a requested erase or secure |
> +| | erase procedure. |
> ++------+-----------------------------------------------------------------------+
> +|10:63 | Reserved / Unused |
> ++------+-----------------------------------------------------------------------+
>
> **H_SCM_PERFORMANCE_STATS**
>
> --
> 2.26.2
>
--
Cheers
~ Vaibhav
^ permalink raw reply
* Re: [PATCH v12 0/6] powerpc/papr_scm: Add support for reporting nvdimm health
From: Vaibhav Jain @ 2020-06-15 12:48 UTC (permalink / raw)
To: linuxppc-dev, linux-nvdimm, linux-kernel
Cc: Santosh Sivaraj, Aneesh Kumar K . V, Steven Rostedt,
Oliver O'Halloran, Dan Williams, Ira Weiny
In-Reply-To: <20200615122644.31887-1-vaibhav@linux.ibm.com>
This accidently got reposted. Please ignore.
v13 version of the patch series located at
https://lore.kernel.org/linux-nvdimm/20200615124407.32596-1-vaibhav@linux.ibm.com
Vaibhav Jain <vaibhav@linux.ibm.com> writes:
> Changes since v11 [1]:
> * Minor update to 'papr_pdsm.h' fixing a misleading comment about
> 'possible' padding being added by GCC which doesn't apply in case
> structs are marked as __packed.
> * Fix the order of initialization of 'struct nd_papr_pdsm_health' in
> papr_pdsm_health().
> * Added acks from Ira for various patches.
>
> [1] https://lore.kernel.org/linux-nvdimm/20200607131339.476036-1-vaibhav@linux.ibm.com
> ---
>
> The PAPR standard[2][4] provides mechanisms to query the health and
> performance stats of an NVDIMM via various hcalls as described in
> Ref[3]. Until now these stats were never available nor exposed to the
> user-space tools like 'ndctl'. This is partly due to PAPR platform not
> having support for ACPI and NFIT. Hence 'ndctl' is unable to query and
> report the dimm health status and a user had no way to determine the
> current health status of a NDVIMM.
>
> To overcome this limitation, this patch-set updates papr_scm kernel
> module to query and fetch NVDIMM health stats using hcalls described
> in Ref[3]. This health and performance stats are then exposed to
> userspace via sysfs and PAPR-NVDIMM-Specific-Methods(PDSM) issued by
> libndctl.
>
> These changes coupled with proposed ndtcl changes located at Ref[5]
> should provide a way for the user to retrieve NVDIMM health status
> using ndtcl.
>
> Below is a sample output using proposed kernel + ndctl for PAPR NVDIMM
> in a emulation environment:
>
> # ndctl list -DH
> [
> {
> "dev":"nmem0",
> "health":{
> "health_state":"fatal",
> "shutdown_state":"dirty"
> }
> }
> ]
>
> Dimm health report output on a pseries guest lpar with vPMEM or HMS
> based NVDIMMs that are in perfectly healthy conditions:
>
> # ndctl list -d nmem0 -H
> [
> {
> "dev":"nmem0",
> "health":{
> "health_state":"ok",
> "shutdown_state":"clean"
> }
> }
> ]
>
> PAPR NVDIMM-Specific-Methods(PDSM)
> ==================================
>
> PDSM requests are issued by vendor specific code in libndctl to
> execute certain operations or fetch information from NVDIMMS. PDSMs
> requests can be sent to papr_scm module via libndctl(userspace) and
> libnvdimm (kernel) using the ND_CMD_CALL ioctl command which can be
> handled in the dimm control function papr_scm_ndctl(). Current
> patchset proposes a single PDSM to retrieve NVDIMM health, defined in
> the newly introduced uapi header named 'papr_pdsm.h'. Support for
> more PDSMs will be added in future.
>
> Structure of the patch-set
> ==========================
>
> The patch-set starts with a doc patch documenting details of hcall
> H_SCM_HEALTH. Second patch exports kernel symbol seq_buf_printf()
> thats used in subsequent patches to generate sysfs attribute content.
>
> Third patch implements support for fetching NVDIMM health information
> from PHYP and partially exposing it to user-space via a NVDIMM sysfs
> flag.
>
> Fourth patch updates papr_scm_ndctl() to handle a possible error case
> and also improve debug logging.
>
> Fifth patch deals with implementing support for servicing PDSM
> commands in papr_scm module.
>
> Finally the last patch implements support for servicing PDSM
> 'PAPR_PDSM_HEALTH' that returns the NVDIMM health information to
> libndctl.
>
> References:
> [2] "Power Architecture Platform Reference"
> https://en.wikipedia.org/wiki/Power_Architecture_Platform_Reference
> [3] commit 58b278f568f0
> ("powerpc: Provide initial documentation for PAPR hcalls")
> [4] "Linux on Power Architecture Platform Reference"
> https://members.openpowerfoundation.org/document/dl/469
> [5] https://github.com/vaibhav92/ndctl/tree/papr_scm_health_v12
>
> ---
>
> Vaibhav Jain (6):
> powerpc: Document details on H_SCM_HEALTH hcall
> seq_buf: Export seq_buf_printf
> powerpc/papr_scm: Fetch nvdimm health information from PHYP
> powerpc/papr_scm: Improve error logging and handling papr_scm_ndctl()
> ndctl/papr_scm,uapi: Add support for PAPR nvdimm specific methods
> powerpc/papr_scm: Implement support for PAPR_PDSM_HEALTH
>
> Documentation/ABI/testing/sysfs-bus-papr-pmem | 27 ++
> Documentation/powerpc/papr_hcalls.rst | 46 ++-
> arch/powerpc/include/uapi/asm/papr_pdsm.h | 125 ++++++
> arch/powerpc/platforms/pseries/papr_scm.c | 373 +++++++++++++++++-
> include/uapi/linux/ndctl.h | 1 +
> lib/seq_buf.c | 1 +
> 6 files changed, 562 insertions(+), 11 deletions(-)
> create mode 100644 Documentation/ABI/testing/sysfs-bus-papr-pmem
> create mode 100644 arch/powerpc/include/uapi/asm/papr_pdsm.h
>
> --
> 2.26.2
>
--
Cheers
~ Vaibhav
^ permalink raw reply
* Re: [PATCH v13 2/6] seq_buf: Export seq_buf_printf
From: Borislav Petkov @ 2020-06-15 12:55 UTC (permalink / raw)
To: Vaibhav Jain
Cc: Santosh Sivaraj, Ira Weiny, linux-nvdimm, Cezary Rojewski,
linux-kernel, Steven Rostedt, Piotr Maziarz, Christoph Hellwig,
Oliver O'Halloran, Aneesh Kumar K . V, Dan Williams,
linuxppc-dev
In-Reply-To: <20200615124407.32596-3-vaibhav@linux.ibm.com>
On Mon, Jun 15, 2020 at 06:14:03PM +0530, Vaibhav Jain wrote:
> 'seq_buf' provides a very useful abstraction for writing to a string
> buffer without needing to worry about it over-flowing. However even
> though the API has been stable for couple of years now its still not
> exported to kernel loadable modules limiting its usage.
>
> Hence this patch proposes update to 'seq_buf.c' to mark
> seq_buf_printf() which is part of the seq_buf API to be exported to
> kernel loadable GPL modules. This symbol will be used in later parts
> of this patch-set to simplify content creation for a sysfs attribute.
>
> Cc: Piotr Maziarz <piotrx.maziarz@linux.intel.com>
> Cc: Cezary Rojewski <cezary.rojewski@intel.com>
> Cc: Christoph Hellwig <hch@infradead.org>
> Cc: Steven Rostedt <rostedt@goodmis.org>
> Cc: Borislav Petkov <bp@alien8.de>
> Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
> Signed-off-by: Vaibhav Jain <vaibhav@linux.ibm.com>
> ---
> Changelog:
>
> v12..v13:
> * None
>
> v11..v12:
> * None
Can you please resend your patchset once a week like everyone else and
not flood inboxes with it?
--
Regards/Gruss,
Boris.
https://people.kernel.org/tglx/notes-about-netiquette
^ permalink raw reply
* [PATCH 2/3] mm: Allow arches to provide ptep_get()
From: Christophe Leroy @ 2020-06-15 12:57 UTC (permalink / raw)
To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman,
Will Deacon, Andrew Morton, Peter Zijlstra (Intel)
Cc: linux-mm, linuxppc-dev, linux-kernel
In-Reply-To: <cover.1592225557.git.christophe.leroy@csgroup.eu>
Since commit 2ab3a0a02905 ("READ_ONCE: Enforce atomicity for
{READ,WRITE}_ONCE() memory accesses"), it is not possible anymore
to use READ_ONCE() to access complex page table entries like
the one defined for powerpc 8xx with 16k size pages.
Define a ptep_get() helper that architectures can override instead
of performing a READ_ONCE() on the page table entry pointer.
Fixes: 2ab3a0a02905 ("READ_ONCE: Enforce atomicity for {READ,WRITE}_ONCE() memory accesses")
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
include/asm-generic/hugetlb.h | 2 +-
include/linux/pgtable.h | 7 +++++++
mm/gup.c | 2 +-
3 files changed, 9 insertions(+), 2 deletions(-)
diff --git a/include/asm-generic/hugetlb.h b/include/asm-generic/hugetlb.h
index 40f85decc2ee..8e1e6244a89d 100644
--- a/include/asm-generic/hugetlb.h
+++ b/include/asm-generic/hugetlb.h
@@ -122,7 +122,7 @@ static inline int huge_ptep_set_access_flags(struct vm_area_struct *vma,
#ifndef __HAVE_ARCH_HUGE_PTEP_GET
static inline pte_t huge_ptep_get(pte_t *ptep)
{
- return READ_ONCE(*ptep);
+ return ptep_get(ptep);
}
#endif
diff --git a/include/linux/pgtable.h b/include/linux/pgtable.h
index 32b6c52d41b9..56c1e8eb7bb0 100644
--- a/include/linux/pgtable.h
+++ b/include/linux/pgtable.h
@@ -249,6 +249,13 @@ static inline pte_t ptep_get_and_clear(struct mm_struct *mm,
}
#endif
+#ifndef __HAVE_ARCH_PTEP_GET
+static inline pte_t ptep_get(pte_t *ptep)
+{
+ return READ_ONCE(*ptep);
+}
+#endif
+
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
#ifndef __HAVE_ARCH_PMDP_HUGE_GET_AND_CLEAR
static inline pmd_t pmdp_huge_get_and_clear(struct mm_struct *mm,
diff --git a/mm/gup.c b/mm/gup.c
index 761df4944ef5..6f47697f8fb0 100644
--- a/mm/gup.c
+++ b/mm/gup.c
@@ -2196,7 +2196,7 @@ static inline pte_t gup_get_pte(pte_t *ptep)
*/
static inline pte_t gup_get_pte(pte_t *ptep)
{
- return READ_ONCE(*ptep);
+ return ptep_get(ptep);
}
#endif /* CONFIG_GUP_GET_PTE_LOW_HIGH */
--
2.25.0
^ permalink raw reply related
* [PATCH 1/3] mm/gup: Use huge_ptep_get() in gup_hugepte()
From: Christophe Leroy @ 2020-06-15 12:57 UTC (permalink / raw)
To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman,
Will Deacon, Andrew Morton, Peter Zijlstra (Intel)
Cc: linux-mm, linuxppc-dev, linux-kernel
In-Reply-To: <cover.1592225557.git.christophe.leroy@csgroup.eu>
gup_hugepte() reads hugepage table entries, it can't read
them directly, huge_ptep_get() must be used.
Fixes: 2ab3a0a02905 ("READ_ONCE: Enforce atomicity for {READ,WRITE}_ONCE() memory accesses")
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
mm/gup.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/mm/gup.c b/mm/gup.c
index de9e36262ccb..761df4944ef5 100644
--- a/mm/gup.c
+++ b/mm/gup.c
@@ -2425,7 +2425,7 @@ static int gup_hugepte(pte_t *ptep, unsigned long sz, unsigned long addr,
if (pte_end < end)
end = pte_end;
- pte = READ_ONCE(*ptep);
+ pte = huge_ptep_get(ptep);
if (!pte_access_permitted(pte, flags & FOLL_WRITE))
return 0;
--
2.25.0
^ permalink raw reply related
* [PATCH 0/3] Fix build failure with v5.8-rc1
From: Christophe Leroy @ 2020-06-15 12:57 UTC (permalink / raw)
To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman,
Will Deacon, Andrew Morton, Peter Zijlstra (Intel)
Cc: linux-mm, linuxppc-dev, linux-kernel
Commit 2ab3a0a02905 ("READ_ONCE: Enforce atomicity for
{READ,WRITE}_ONCE() memory accesses") leads to following build
failure on powerpc 8xx.
To fix it, this small series introduces a new helper named ptep_get()
to replace the direct access with READ_ONCE(). This new helper
can be overriden by architectures.
CC mm/gup.o
In file included from ./include/linux/kernel.h:11:0,
from mm/gup.c:2:
In function 'gup_hugepte.constprop',
inlined from 'gup_huge_pd.isra.79' at mm/gup.c:2465:8:
./include/linux/compiler.h:392:38: error: call to '__compiletime_assert_222' declared with attribute error: Unsupported access size for {READ,WRITE}_ONCE().
_compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__)
^
./include/linux/compiler.h:373:4: note: in definition of macro '__compiletime_assert'
prefix ## suffix(); \
^
./include/linux/compiler.h:392:2: note: in expansion of macro '_compiletime_assert'
_compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__)
^
./include/linux/compiler.h:405:2: note: in expansion of macro 'compiletime_assert'
compiletime_assert(__native_word(t) || sizeof(t) == sizeof(long long), \
^
./include/linux/compiler.h:291:2: note: in expansion of macro 'compiletime_assert_rwonce_type'
compiletime_assert_rwonce_type(x); \
^
mm/gup.c:2428:8: note: in expansion of macro 'READ_ONCE'
pte = READ_ONCE(*ptep);
^
In function 'gup_get_pte',
inlined from 'gup_pte_range' at mm/gup.c:2228:9,
inlined from 'gup_pmd_range' at mm/gup.c:2613:15,
inlined from 'gup_pud_range' at mm/gup.c:2641:15,
inlined from 'gup_p4d_range' at mm/gup.c:2666:15,
inlined from 'gup_pgd_range' at mm/gup.c:2694:15,
inlined from 'internal_get_user_pages_fast' at mm/gup.c:2795:3:
./include/linux/compiler.h:392:38: error: call to '__compiletime_assert_219' declared with attribute error: Unsupported access size for {READ,WRITE}_ONCE().
_compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__)
^
./include/linux/compiler.h:373:4: note: in definition of macro '__compiletime_assert'
prefix ## suffix(); \
^
./include/linux/compiler.h:392:2: note: in expansion of macro '_compiletime_assert'
_compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__)
^
./include/linux/compiler.h:405:2: note: in expansion of macro 'compiletime_assert'
compiletime_assert(__native_word(t) || sizeof(t) == sizeof(long long), \
^
./include/linux/compiler.h:291:2: note: in expansion of macro 'compiletime_assert_rwonce_type'
compiletime_assert_rwonce_type(x); \
^
mm/gup.c:2199:9: note: in expansion of macro 'READ_ONCE'
return READ_ONCE(*ptep);
^
make[2]: *** [mm/gup.o] Error 1
Christophe Leroy (3):
mm/gup: Use huge_ptep_get() in gup_hugepte()
mm: Allow arches to provide ptep_get()
powerpc/8xx: Provide ptep_get() with 16k pages
arch/powerpc/include/asm/nohash/32/pgtable.h | 10 ++++++++++
include/asm-generic/hugetlb.h | 2 +-
include/linux/pgtable.h | 7 +++++++
mm/gup.c | 4 ++--
4 files changed, 20 insertions(+), 3 deletions(-)
--
2.25.0
^ permalink raw reply
* [PATCH 3/3] powerpc/8xx: Provide ptep_get() with 16k pages
From: Christophe Leroy @ 2020-06-15 12:57 UTC (permalink / raw)
To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman,
Will Deacon, Andrew Morton, Peter Zijlstra (Intel)
Cc: linux-mm, linuxppc-dev, linux-kernel
In-Reply-To: <cover.1592225557.git.christophe.leroy@csgroup.eu>
READ_ONCE() now enforces atomic read, which leads to:
CC mm/gup.o
In file included from ./include/linux/kernel.h:11:0,
from mm/gup.c:2:
In function 'gup_hugepte.constprop',
inlined from 'gup_huge_pd.isra.79' at mm/gup.c:2465:8:
./include/linux/compiler.h:392:38: error: call to '__compiletime_assert_222' declared with attribute error: Unsupported access size for {READ,WRITE}_ONCE().
_compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__)
^
./include/linux/compiler.h:373:4: note: in definition of macro '__compiletime_assert'
prefix ## suffix(); \
^
./include/linux/compiler.h:392:2: note: in expansion of macro '_compiletime_assert'
_compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__)
^
./include/linux/compiler.h:405:2: note: in expansion of macro 'compiletime_assert'
compiletime_assert(__native_word(t) || sizeof(t) == sizeof(long long), \
^
./include/linux/compiler.h:291:2: note: in expansion of macro 'compiletime_assert_rwonce_type'
compiletime_assert_rwonce_type(x); \
^
mm/gup.c:2428:8: note: in expansion of macro 'READ_ONCE'
pte = READ_ONCE(*ptep);
^
In function 'gup_get_pte',
inlined from 'gup_pte_range' at mm/gup.c:2228:9,
inlined from 'gup_pmd_range' at mm/gup.c:2613:15,
inlined from 'gup_pud_range' at mm/gup.c:2641:15,
inlined from 'gup_p4d_range' at mm/gup.c:2666:15,
inlined from 'gup_pgd_range' at mm/gup.c:2694:15,
inlined from 'internal_get_user_pages_fast' at mm/gup.c:2795:3:
./include/linux/compiler.h:392:38: error: call to '__compiletime_assert_219' declared with attribute error: Unsupported access size for {READ,WRITE}_ONCE().
_compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__)
^
./include/linux/compiler.h:373:4: note: in definition of macro '__compiletime_assert'
prefix ## suffix(); \
^
./include/linux/compiler.h:392:2: note: in expansion of macro '_compiletime_assert'
_compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__)
^
./include/linux/compiler.h:405:2: note: in expansion of macro 'compiletime_assert'
compiletime_assert(__native_word(t) || sizeof(t) == sizeof(long long), \
^
./include/linux/compiler.h:291:2: note: in expansion of macro 'compiletime_assert_rwonce_type'
compiletime_assert_rwonce_type(x); \
^
mm/gup.c:2199:9: note: in expansion of macro 'READ_ONCE'
return READ_ONCE(*ptep);
^
make[2]: *** [mm/gup.o] Error 1
Define ptep_get() on 8xx when using 16k pages.
Fixes: 2ab3a0a02905 ("READ_ONCE: Enforce atomicity for {READ,WRITE}_ONCE() memory accesses")
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
arch/powerpc/include/asm/nohash/32/pgtable.h | 10 ++++++++++
1 file changed, 10 insertions(+)
diff --git a/arch/powerpc/include/asm/nohash/32/pgtable.h b/arch/powerpc/include/asm/nohash/32/pgtable.h
index b56f14160ae5..77addb599ce7 100644
--- a/arch/powerpc/include/asm/nohash/32/pgtable.h
+++ b/arch/powerpc/include/asm/nohash/32/pgtable.h
@@ -286,6 +286,16 @@ static inline pte_t ptep_get_and_clear(struct mm_struct *mm, unsigned long addr,
return __pte(pte_update(mm, addr, ptep, ~0, 0, 0));
}
+#if defined(CONFIG_PPC_8xx) && defined(CONFIG_PPC_16K_PAGES)
+#define __HAVE_ARCH_PTEP_GET
+static inline pte_t ptep_get(pte_t *ptep)
+{
+ pte_t pte = {READ_ONCE(ptep->pte), 0, 0, 0};
+
+ return pte;
+}
+#endif
+
#define __HAVE_ARCH_PTEP_SET_WRPROTECT
static inline void ptep_set_wrprotect(struct mm_struct *mm, unsigned long addr,
pte_t *ptep)
--
2.25.0
^ permalink raw reply related
* [PATCH 1/6] exec: cleanup the execve wrappers
From: Christoph Hellwig @ 2020-06-15 13:00 UTC (permalink / raw)
To: Al Viro
Cc: linux-arch, linux-s390, Arnd Bergmann, linux-parisc, x86,
linux-mips, linux-kernel, linux-fsdevel, Luis Chamberlain,
sparclinux, linuxppc-dev, linux-arm-kernel
In-Reply-To: <20200615130032.931285-1-hch@lst.de>
Remove a whole bunch of wrappers that eventually all call
__do_execve_file, and consolidate the execvce helpers to:
(1) __do_execveat, which is the lowest level helper implementing the
actual functionality
(2) do_execvat, which is used by all callers that want native
pointers
(3) do_compat_execve, which is used by all compat syscalls
Signed-off-by: Christoph Hellwig <hch@lst.de>
---
fs/exec.c | 98 +++++++++++------------------------------
include/linux/binfmts.h | 12 ++---
init/main.c | 7 +--
kernel/umh.c | 16 +++----
4 files changed, 41 insertions(+), 92 deletions(-)
diff --git a/fs/exec.c b/fs/exec.c
index e6e8a9a7032784..354fdaa536ae7d 100644
--- a/fs/exec.c
+++ b/fs/exec.c
@@ -1815,10 +1815,7 @@ static int exec_binprm(struct linux_binprm *bprm)
return 0;
}
-/*
- * sys_execve() executes a new program.
- */
-static int __do_execve_file(int fd, struct filename *filename,
+static int __do_execveat(int fd, struct filename *filename,
struct user_arg_ptr argv,
struct user_arg_ptr envp,
int flags, struct file *file)
@@ -1972,74 +1969,16 @@ static int __do_execve_file(int fd, struct filename *filename,
return retval;
}
-static int do_execveat_common(int fd, struct filename *filename,
- struct user_arg_ptr argv,
- struct user_arg_ptr envp,
- int flags)
-{
- return __do_execve_file(fd, filename, argv, envp, flags, NULL);
-}
-
-int do_execve_file(struct file *file, void *__argv, void *__envp)
-{
- struct user_arg_ptr argv = { .ptr.native = __argv };
- struct user_arg_ptr envp = { .ptr.native = __envp };
-
- return __do_execve_file(AT_FDCWD, NULL, argv, envp, 0, file);
-}
-
-int do_execve(struct filename *filename,
- const char __user *const __user *__argv,
- const char __user *const __user *__envp)
-{
- struct user_arg_ptr argv = { .ptr.native = __argv };
- struct user_arg_ptr envp = { .ptr.native = __envp };
- return do_execveat_common(AT_FDCWD, filename, argv, envp, 0);
-}
-
int do_execveat(int fd, struct filename *filename,
const char __user *const __user *__argv,
const char __user *const __user *__envp,
- int flags)
+ int flags, struct file *file)
{
struct user_arg_ptr argv = { .ptr.native = __argv };
struct user_arg_ptr envp = { .ptr.native = __envp };
- return do_execveat_common(fd, filename, argv, envp, flags);
-}
-
-#ifdef CONFIG_COMPAT
-static int compat_do_execve(struct filename *filename,
- const compat_uptr_t __user *__argv,
- const compat_uptr_t __user *__envp)
-{
- struct user_arg_ptr argv = {
- .is_compat = true,
- .ptr.compat = __argv,
- };
- struct user_arg_ptr envp = {
- .is_compat = true,
- .ptr.compat = __envp,
- };
- return do_execveat_common(AT_FDCWD, filename, argv, envp, 0);
-}
-
-static int compat_do_execveat(int fd, struct filename *filename,
- const compat_uptr_t __user *__argv,
- const compat_uptr_t __user *__envp,
- int flags)
-{
- struct user_arg_ptr argv = {
- .is_compat = true,
- .ptr.compat = __argv,
- };
- struct user_arg_ptr envp = {
- .is_compat = true,
- .ptr.compat = __envp,
- };
- return do_execveat_common(fd, filename, argv, envp, flags);
+ return __do_execveat(fd, filename, argv, envp, flags, file);
}
-#endif
void set_binfmt(struct linux_binfmt *new)
{
@@ -2070,7 +2009,7 @@ SYSCALL_DEFINE3(execve,
const char __user *const __user *, argv,
const char __user *const __user *, envp)
{
- return do_execve(getname(filename), argv, envp);
+ return do_execveat(AT_FDCWD, getname(filename), argv, envp, 0, NULL);
}
SYSCALL_DEFINE5(execveat,
@@ -2080,18 +2019,34 @@ SYSCALL_DEFINE5(execveat,
int, flags)
{
int lookup_flags = (flags & AT_EMPTY_PATH) ? LOOKUP_EMPTY : 0;
+ struct filename *name = getname_flags(filename, lookup_flags, NULL);
- return do_execveat(fd,
- getname_flags(filename, lookup_flags, NULL),
- argv, envp, flags);
+ return do_execveat(fd, name, argv, envp, flags, NULL);
}
#ifdef CONFIG_COMPAT
+static int do_compat_execve(int fd, struct filename *filename,
+ const compat_uptr_t __user *__argv,
+ const compat_uptr_t __user *__envp,
+ int flags)
+{
+ struct user_arg_ptr argv = {
+ .is_compat = true,
+ .ptr.compat = __argv,
+ };
+ struct user_arg_ptr envp = {
+ .is_compat = true,
+ .ptr.compat = __envp,
+ };
+
+ return __do_execveat(fd, filename, argv, envp, flags, NULL);
+}
+
COMPAT_SYSCALL_DEFINE3(execve, const char __user *, filename,
const compat_uptr_t __user *, argv,
const compat_uptr_t __user *, envp)
{
- return compat_do_execve(getname(filename), argv, envp);
+ return do_compat_execve(AT_FDCWD, getname(filename), argv, envp, 0);
}
COMPAT_SYSCALL_DEFINE5(execveat, int, fd,
@@ -2101,9 +2056,8 @@ COMPAT_SYSCALL_DEFINE5(execveat, int, fd,
int, flags)
{
int lookup_flags = (flags & AT_EMPTY_PATH) ? LOOKUP_EMPTY : 0;
+ struct filename *name = getname_flags(filename, lookup_flags, NULL);
- return compat_do_execveat(fd,
- getname_flags(filename, lookup_flags, NULL),
- argv, envp, flags);
+ return do_compat_execve(fd, name, argv, envp, flags);
}
#endif
diff --git a/include/linux/binfmts.h b/include/linux/binfmts.h
index 4a20b7517dd036..bed702e4b1fbd9 100644
--- a/include/linux/binfmts.h
+++ b/include/linux/binfmts.h
@@ -134,13 +134,9 @@ int copy_string_kernel(const char *arg, struct linux_binprm *bprm);
extern void set_binfmt(struct linux_binfmt *new);
extern ssize_t read_code(struct file *, unsigned long, loff_t, size_t);
-extern int do_execve(struct filename *,
- const char __user * const __user *,
- const char __user * const __user *);
-extern int do_execveat(int, struct filename *,
- const char __user * const __user *,
- const char __user * const __user *,
- int);
-int do_execve_file(struct file *file, void *__argv, void *__envp);
+int do_execveat(int fd, struct filename *filename,
+ const char __user *const __user *__argv,
+ const char __user *const __user *__envp,
+ int flags, struct file *file);
#endif /* _LINUX_BINFMTS_H */
diff --git a/init/main.c b/init/main.c
index 0ead83e86b5aa2..838950ea7bca22 100644
--- a/init/main.c
+++ b/init/main.c
@@ -1329,9 +1329,10 @@ static int run_init_process(const char *init_filename)
pr_debug(" with environment:\n");
for (p = envp_init; *p; p++)
pr_debug(" %s\n", *p);
- return do_execve(getname_kernel(init_filename),
- (const char __user *const __user *)argv_init,
- (const char __user *const __user *)envp_init);
+ return do_execveat(AT_FDCWD, getname_kernel(init_filename),
+ (const char __user *const __user *)argv_init,
+ (const char __user *const __user *)envp_init,
+ 0, NULL);
}
static int try_to_run_init_process(const char *init_filename)
diff --git a/kernel/umh.c b/kernel/umh.c
index 79f139a7ca03c6..7aa9a5817582ca 100644
--- a/kernel/umh.c
+++ b/kernel/umh.c
@@ -103,15 +103,13 @@ static int call_usermodehelper_exec_async(void *data)
commit_creds(new);
sub_info->pid = task_pid_nr(current);
- if (sub_info->file) {
- retval = do_execve_file(sub_info->file,
- sub_info->argv, sub_info->envp);
- if (!retval)
- current->flags |= PF_UMH;
- } else
- retval = do_execve(getname_kernel(sub_info->path),
- (const char __user *const __user *)sub_info->argv,
- (const char __user *const __user *)sub_info->envp);
+ retval = do_execveat(AT_FDCWD,
+ sub_info->path ? getname_kernel(sub_info->path) : NULL,
+ (const char __user *const __user *)sub_info->argv,
+ (const char __user *const __user *)sub_info->envp,
+ 0, sub_info->file);
+ if (sub_info->file && !retval)
+ current->flags |= PF_UMH;
out:
sub_info->retval = retval;
/*
--
2.26.2
^ permalink raw reply related
* properly support exec and wait with kernel pointers
From: Christoph Hellwig @ 2020-06-15 13:00 UTC (permalink / raw)
To: Al Viro
Cc: linux-arch, linux-s390, Arnd Bergmann, linux-parisc, x86,
linux-mips, linux-kernel, linux-fsdevel, Luis Chamberlain,
sparclinux, linuxppc-dev, linux-arm-kernel
Hi all,
this series first cleans up the exec code and then adds proper
kernel_execveat and kernel_wait callers instead of relying on the fact
that the early init code and kernel threads implicitly run with
the address limit set to KERNEL_DS.
Note that the cleanup removes the compat execve(at) handlers (almost)
entirely, as we can handle the compat difference very nicely in a
unified codebase. The only exception is x86 where this would list the
handlers twice in the same syscall table due to the messed up x32
design. I had to add an extra compat handler just for that case, but
maybe someone has a better idea.
^ permalink raw reply
* [PATCH 2/6] exec: simplify the compat syscall handling
From: Christoph Hellwig @ 2020-06-15 13:00 UTC (permalink / raw)
To: Al Viro
Cc: linux-arch, linux-s390, Arnd Bergmann, linux-parisc, x86,
linux-mips, linux-kernel, linux-fsdevel, Luis Chamberlain,
sparclinux, linuxppc-dev, linux-arm-kernel
In-Reply-To: <20200615130032.931285-1-hch@lst.de>
The only differenence betweeen the compat exec* syscalls and their
native versions is that compat_ptr sign extension, and the fact that
the pointer arithmetics for the two dimensional arrays needs to use
the compat pointer size. Instead of the compat wrappers and the
struct user_arg_ptr machinery just use in_compat_syscall() to do the
right thing for the compat case deep inside get_user_arg_ptr().
Signed-off-by: Christoph Hellwig <hch@lst.de>
---
arch/arm64/include/asm/unistd32.h | 4 +-
arch/mips/kernel/syscalls/syscall_n32.tbl | 4 +-
arch/mips/kernel/syscalls/syscall_o32.tbl | 4 +-
arch/parisc/kernel/syscalls/syscall.tbl | 4 +-
arch/powerpc/kernel/syscalls/syscall.tbl | 4 +-
arch/s390/kernel/syscalls/syscall.tbl | 4 +-
arch/sparc/kernel/syscalls.S | 4 +-
arch/x86/entry/syscalls/syscall_32.tbl | 4 +-
fs/exec.c | 89 ++++++-------------
include/linux/compat.h | 7 --
include/uapi/asm-generic/unistd.h | 4 +-
tools/include/uapi/asm-generic/unistd.h | 4 +-
.../arch/powerpc/entry/syscalls/syscall.tbl | 4 +-
.../perf/arch/s390/entry/syscalls/syscall.tbl | 4 +-
14 files changed, 53 insertions(+), 91 deletions(-)
diff --git a/arch/arm64/include/asm/unistd32.h b/arch/arm64/include/asm/unistd32.h
index 6d95d0c8bf2f47..141f5d2ff1c34f 100644
--- a/arch/arm64/include/asm/unistd32.h
+++ b/arch/arm64/include/asm/unistd32.h
@@ -33,7 +33,7 @@ __SYSCALL(__NR_link, sys_link)
#define __NR_unlink 10
__SYSCALL(__NR_unlink, sys_unlink)
#define __NR_execve 11
-__SYSCALL(__NR_execve, compat_sys_execve)
+__SYSCALL(__NR_execve, sys_execve)
#define __NR_chdir 12
__SYSCALL(__NR_chdir, sys_chdir)
/* 13 was sys_time */
@@ -785,7 +785,7 @@ __SYSCALL(__NR_memfd_create, sys_memfd_create)
#define __NR_bpf 386
__SYSCALL(__NR_bpf, sys_bpf)
#define __NR_execveat 387
-__SYSCALL(__NR_execveat, compat_sys_execveat)
+__SYSCALL(__NR_execveat, sys_execveat)
#define __NR_userfaultfd 388
__SYSCALL(__NR_userfaultfd, sys_userfaultfd)
#define __NR_membarrier 389
diff --git a/arch/mips/kernel/syscalls/syscall_n32.tbl b/arch/mips/kernel/syscalls/syscall_n32.tbl
index f777141f52568f..e861b5ab7179c9 100644
--- a/arch/mips/kernel/syscalls/syscall_n32.tbl
+++ b/arch/mips/kernel/syscalls/syscall_n32.tbl
@@ -64,7 +64,7 @@
54 n32 getsockopt compat_sys_getsockopt
55 n32 clone __sys_clone
56 n32 fork __sys_fork
-57 n32 execve compat_sys_execve
+57 n32 execve sys_execve
58 n32 exit sys_exit
59 n32 wait4 compat_sys_wait4
60 n32 kill sys_kill
@@ -328,7 +328,7 @@
317 n32 getrandom sys_getrandom
318 n32 memfd_create sys_memfd_create
319 n32 bpf sys_bpf
-320 n32 execveat compat_sys_execveat
+320 n32 execveat sys_execveat
321 n32 userfaultfd sys_userfaultfd
322 n32 membarrier sys_membarrier
323 n32 mlock2 sys_mlock2
diff --git a/arch/mips/kernel/syscalls/syscall_o32.tbl b/arch/mips/kernel/syscalls/syscall_o32.tbl
index 13280625d312e9..bba80f74e9968e 100644
--- a/arch/mips/kernel/syscalls/syscall_o32.tbl
+++ b/arch/mips/kernel/syscalls/syscall_o32.tbl
@@ -18,7 +18,7 @@
8 o32 creat sys_creat
9 o32 link sys_link
10 o32 unlink sys_unlink
-11 o32 execve sys_execve compat_sys_execve
+11 o32 execve sys_execve
12 o32 chdir sys_chdir
13 o32 time sys_time32
14 o32 mknod sys_mknod
@@ -367,7 +367,7 @@
353 o32 getrandom sys_getrandom
354 o32 memfd_create sys_memfd_create
355 o32 bpf sys_bpf
-356 o32 execveat sys_execveat compat_sys_execveat
+356 o32 execveat sys_execveat
357 o32 userfaultfd sys_userfaultfd
358 o32 membarrier sys_membarrier
359 o32 mlock2 sys_mlock2
diff --git a/arch/parisc/kernel/syscalls/syscall.tbl b/arch/parisc/kernel/syscalls/syscall.tbl
index 5a758fa6ec5242..23fa0d0edf3384 100644
--- a/arch/parisc/kernel/syscalls/syscall.tbl
+++ b/arch/parisc/kernel/syscalls/syscall.tbl
@@ -18,7 +18,7 @@
8 common creat sys_creat
9 common link sys_link
10 common unlink sys_unlink
-11 common execve sys_execve compat_sys_execve
+11 common execve sys_execve
12 common chdir sys_chdir
13 32 time sys_time32
13 64 time sys_time
@@ -385,7 +385,7 @@
339 common getrandom sys_getrandom
340 common memfd_create sys_memfd_create
341 common bpf sys_bpf
-342 common execveat sys_execveat compat_sys_execveat
+342 common execveat sys_execveat
343 common membarrier sys_membarrier
344 common userfaultfd sys_userfaultfd
345 common mlock2 sys_mlock2
diff --git a/arch/powerpc/kernel/syscalls/syscall.tbl b/arch/powerpc/kernel/syscalls/syscall.tbl
index f833a319082247..c52cdab89dc0ae 100644
--- a/arch/powerpc/kernel/syscalls/syscall.tbl
+++ b/arch/powerpc/kernel/syscalls/syscall.tbl
@@ -20,7 +20,7 @@
8 common creat sys_creat
9 common link sys_link
10 common unlink sys_unlink
-11 nospu execve sys_execve compat_sys_execve
+11 nospu execve sys_execve
12 common chdir sys_chdir
13 32 time sys_time32
13 64 time sys_time
@@ -460,7 +460,7 @@
359 common getrandom sys_getrandom
360 common memfd_create sys_memfd_create
361 common bpf sys_bpf
-362 nospu execveat sys_execveat compat_sys_execveat
+362 nospu execveat sys_execveat
363 32 switch_endian sys_ni_syscall
363 64 switch_endian sys_switch_endian
363 spu switch_endian sys_ni_syscall
diff --git a/arch/s390/kernel/syscalls/syscall.tbl b/arch/s390/kernel/syscalls/syscall.tbl
index bfdcb763395735..bd2275db2026ea 100644
--- a/arch/s390/kernel/syscalls/syscall.tbl
+++ b/arch/s390/kernel/syscalls/syscall.tbl
@@ -18,7 +18,7 @@
8 common creat sys_creat sys_creat
9 common link sys_link sys_link
10 common unlink sys_unlink sys_unlink
-11 common execve sys_execve compat_sys_execve
+11 common execve sys_execve sys_execve
12 common chdir sys_chdir sys_chdir
13 32 time - sys_time32
14 common mknod sys_mknod sys_mknod
@@ -361,7 +361,7 @@
351 common bpf sys_bpf sys_bpf
352 common s390_pci_mmio_write sys_s390_pci_mmio_write sys_s390_pci_mmio_write
353 common s390_pci_mmio_read sys_s390_pci_mmio_read sys_s390_pci_mmio_read
-354 common execveat sys_execveat compat_sys_execveat
+354 common execveat sys_execveat sys_execveat
355 common userfaultfd sys_userfaultfd sys_userfaultfd
356 common membarrier sys_membarrier sys_membarrier
357 common recvmmsg sys_recvmmsg compat_sys_recvmmsg_time32
diff --git a/arch/sparc/kernel/syscalls.S b/arch/sparc/kernel/syscalls.S
index db42b4fb370844..70463972152a92 100644
--- a/arch/sparc/kernel/syscalls.S
+++ b/arch/sparc/kernel/syscalls.S
@@ -16,12 +16,12 @@ sys64_execveat:
sunos_execv:
mov %g0, %o2
sys32_execve:
- set compat_sys_execve, %g1
+ set sys_execve, %g1
jmpl %g1, %g0
flushw
sys32_execveat:
- set compat_sys_execveat, %g1
+ set sys_execveat, %g1
jmpl %g1, %g0
flushw
#endif
diff --git a/arch/x86/entry/syscalls/syscall_32.tbl b/arch/x86/entry/syscalls/syscall_32.tbl
index d8f8a1a69ed11f..2b1eccd3f8f697 100644
--- a/arch/x86/entry/syscalls/syscall_32.tbl
+++ b/arch/x86/entry/syscalls/syscall_32.tbl
@@ -22,7 +22,7 @@
8 i386 creat sys_creat
9 i386 link sys_link
10 i386 unlink sys_unlink
-11 i386 execve sys_execve compat_sys_execve
+11 i386 execve sys_execve
12 i386 chdir sys_chdir
13 i386 time sys_time32
14 i386 mknod sys_mknod
@@ -369,7 +369,7 @@
355 i386 getrandom sys_getrandom
356 i386 memfd_create sys_memfd_create
357 i386 bpf sys_bpf
-358 i386 execveat sys_execveat compat_sys_execveat
+358 i386 execveat sys_execveat
359 i386 socket sys_socket
360 i386 socketpair sys_socketpair
361 i386 bind sys_bind
diff --git a/fs/exec.c b/fs/exec.c
index 354fdaa536ae7d..94107eceda8a67 100644
--- a/fs/exec.c
+++ b/fs/exec.c
@@ -386,34 +386,25 @@ static int bprm_mm_init(struct linux_binprm *bprm)
return err;
}
-struct user_arg_ptr {
-#ifdef CONFIG_COMPAT
- bool is_compat;
-#endif
- union {
- const char __user *const __user *native;
-#ifdef CONFIG_COMPAT
- const compat_uptr_t __user *compat;
-#endif
- } ptr;
-};
-
-static const char __user *get_user_arg_ptr(struct user_arg_ptr argv, int nr)
+static const char __user *
+get_user_arg_ptr(const char __user *const __user *argv, int nr)
{
const char __user *native;
#ifdef CONFIG_COMPAT
- if (unlikely(argv.is_compat)) {
+ if (in_compat_syscall()) {
+ const compat_uptr_t __user *compat_argv =
+ compat_ptr((unsigned long)argv);
compat_uptr_t compat;
- if (get_user(compat, argv.ptr.compat + nr))
+ if (get_user(compat, compat_argv + nr))
return ERR_PTR(-EFAULT);
return compat_ptr(compat);
}
#endif
- if (get_user(native, argv.ptr.native + nr))
+ if (get_user(native, argv + nr))
return ERR_PTR(-EFAULT);
return native;
@@ -422,11 +413,11 @@ static const char __user *get_user_arg_ptr(struct user_arg_ptr argv, int nr)
/*
* count() counts the number of strings in array ARGV.
*/
-static int count(struct user_arg_ptr argv, int max)
+static int count(const char __user *const __user *argv, int max)
{
int i = 0;
- if (argv.ptr.native != NULL) {
+ if (argv) {
for (;;) {
const char __user *p = get_user_arg_ptr(argv, i);
@@ -449,7 +440,8 @@ static int count(struct user_arg_ptr argv, int max)
}
static int prepare_arg_pages(struct linux_binprm *bprm,
- struct user_arg_ptr argv, struct user_arg_ptr envp)
+ const char __user *const __user *argv,
+ const char __user *const __user *envp)
{
unsigned long limit, ptr_size;
@@ -497,7 +489,7 @@ static int prepare_arg_pages(struct linux_binprm *bprm,
* processes's memory to the new process's stack. The call to get_user_pages()
* ensures the destination page is created and not swapped out.
*/
-static int copy_strings(int argc, struct user_arg_ptr argv,
+static int copy_strings(int argc, const char __user *const __user *argv,
struct linux_binprm *bprm)
{
struct page *kmapped_page = NULL;
@@ -1815,10 +1807,10 @@ static int exec_binprm(struct linux_binprm *bprm)
return 0;
}
-static int __do_execveat(int fd, struct filename *filename,
- struct user_arg_ptr argv,
- struct user_arg_ptr envp,
- int flags, struct file *file)
+int do_execveat(int fd, struct filename *filename,
+ const char __user *const __user *argv,
+ const char __user *const __user *envp,
+ int flags, struct file *file)
{
char *pathbuf = NULL;
struct linux_binprm *bprm;
@@ -1969,17 +1961,6 @@ static int __do_execveat(int fd, struct filename *filename,
return retval;
}
-int do_execveat(int fd, struct filename *filename,
- const char __user *const __user *__argv,
- const char __user *const __user *__envp,
- int flags, struct file *file)
-{
- struct user_arg_ptr argv = { .ptr.native = __argv };
- struct user_arg_ptr envp = { .ptr.native = __envp };
-
- return __do_execveat(fd, filename, argv, envp, flags, file);
-}
-
void set_binfmt(struct linux_binfmt *new)
{
struct mm_struct *mm = current->mm;
@@ -2024,40 +2005,28 @@ SYSCALL_DEFINE5(execveat,
return do_execveat(fd, name, argv, envp, flags, NULL);
}
-#ifdef CONFIG_COMPAT
-static int do_compat_execve(int fd, struct filename *filename,
- const compat_uptr_t __user *__argv,
- const compat_uptr_t __user *__envp,
- int flags)
-{
- struct user_arg_ptr argv = {
- .is_compat = true,
- .ptr.compat = __argv,
- };
- struct user_arg_ptr envp = {
- .is_compat = true,
- .ptr.compat = __envp,
- };
-
- return __do_execveat(fd, filename, argv, envp, flags, NULL);
-}
-
+/*
+ * x32 syscalls are listed in the same table as x86_64 ones, so we need to
+ * define compat syscalls that are exactly the same as the native version for
+ * the syscall table machinery to work. Sigh..
+ */
+#ifdef CONFIG_X86_X32
COMPAT_SYSCALL_DEFINE3(execve, const char __user *, filename,
- const compat_uptr_t __user *, argv,
- const compat_uptr_t __user *, envp)
+ const char __user *const __user *, argv,
+ const char __user *const __user *, envp)
{
- return do_compat_execve(AT_FDCWD, getname(filename), argv, envp, 0);
+ return do_execveat(AT_FDCWD, getname(filename), argv, envp, 0, NULL);
}
COMPAT_SYSCALL_DEFINE5(execveat, int, fd,
const char __user *, filename,
- const compat_uptr_t __user *, argv,
- const compat_uptr_t __user *, envp,
+ const char __user *const __user *, argv,
+ const char __user *const __user *, envp,
int, flags)
{
int lookup_flags = (flags & AT_EMPTY_PATH) ? LOOKUP_EMPTY : 0;
struct filename *name = getname_flags(filename, lookup_flags, NULL);
- return do_compat_execve(fd, name, argv, envp, flags);
+ return do_execveat(fd, name, argv, envp, flags, NULL);
}
-#endif
+#endif /* CONFIG_X86_X32 */
diff --git a/include/linux/compat.h b/include/linux/compat.h
index e90100c0de72e4..5e8f6a588e0d43 100644
--- a/include/linux/compat.h
+++ b/include/linux/compat.h
@@ -752,10 +752,6 @@ asmlinkage long compat_sys_recvmsg(int fd, struct compat_msghdr __user *msg,
asmlinkage long compat_sys_keyctl(u32 option,
u32 arg2, u32 arg3, u32 arg4, u32 arg5);
-/* arch/example/kernel/sys_example.c */
-asmlinkage long compat_sys_execve(const char __user *filename, const compat_uptr_t __user *argv,
- const compat_uptr_t __user *envp);
-
/* mm/fadvise.c: No generic prototype for fadvise64_64 */
/* mm/, CONFIG_MMU only */
@@ -806,9 +802,6 @@ asmlinkage ssize_t compat_sys_process_vm_writev(compat_pid_t pid,
const struct compat_iovec __user *lvec,
compat_ulong_t liovcnt, const struct compat_iovec __user *rvec,
compat_ulong_t riovcnt, compat_ulong_t flags);
-asmlinkage long compat_sys_execveat(int dfd, const char __user *filename,
- const compat_uptr_t __user *argv,
- const compat_uptr_t __user *envp, int flags);
asmlinkage ssize_t compat_sys_preadv2(compat_ulong_t fd,
const struct compat_iovec __user *vec,
compat_ulong_t vlen, u32 pos_low, u32 pos_high, rwf_t flags);
diff --git a/include/uapi/asm-generic/unistd.h b/include/uapi/asm-generic/unistd.h
index f4a01305d9a65c..c639d04a094b8b 100644
--- a/include/uapi/asm-generic/unistd.h
+++ b/include/uapi/asm-generic/unistd.h
@@ -640,7 +640,7 @@ __SC_COMP(__NR_keyctl, sys_keyctl, compat_sys_keyctl)
#define __NR_clone 220
__SYSCALL(__NR_clone, sys_clone)
#define __NR_execve 221
-__SC_COMP(__NR_execve, sys_execve, compat_sys_execve)
+__SYSCALL(__NR_execve, sys_execve)
#define __NR3264_mmap 222
__SC_3264(__NR3264_mmap, sys_mmap2, sys_mmap)
@@ -751,7 +751,7 @@ __SYSCALL(__NR_memfd_create, sys_memfd_create)
#define __NR_bpf 280
__SYSCALL(__NR_bpf, sys_bpf)
#define __NR_execveat 281
-__SC_COMP(__NR_execveat, sys_execveat, compat_sys_execveat)
+__SYSCALL(__NR_execveat, sys_execveat)
#define __NR_userfaultfd 282
__SYSCALL(__NR_userfaultfd, sys_userfaultfd)
#define __NR_membarrier 283
diff --git a/tools/include/uapi/asm-generic/unistd.h b/tools/include/uapi/asm-generic/unistd.h
index 3a3201e4618ef8..a6dbc8af8bd577 100644
--- a/tools/include/uapi/asm-generic/unistd.h
+++ b/tools/include/uapi/asm-generic/unistd.h
@@ -640,7 +640,7 @@ __SC_COMP(__NR_keyctl, sys_keyctl, compat_sys_keyctl)
#define __NR_clone 220
__SYSCALL(__NR_clone, sys_clone)
#define __NR_execve 221
-__SC_COMP(__NR_execve, sys_execve, compat_sys_execve)
+__SYSCALL(__NR_execve, sys_execve)
#define __NR3264_mmap 222
__SC_3264(__NR3264_mmap, sys_mmap2, sys_mmap)
@@ -751,7 +751,7 @@ __SYSCALL(__NR_memfd_create, sys_memfd_create)
#define __NR_bpf 280
__SYSCALL(__NR_bpf, sys_bpf)
#define __NR_execveat 281
-__SC_COMP(__NR_execveat, sys_execveat, compat_sys_execveat)
+__SYSCALL(__NR_execveat, sys_execveat)
#define __NR_userfaultfd 282
__SYSCALL(__NR_userfaultfd, sys_userfaultfd)
#define __NR_membarrier 283
diff --git a/tools/perf/arch/powerpc/entry/syscalls/syscall.tbl b/tools/perf/arch/powerpc/entry/syscalls/syscall.tbl
index 35b61bfc1b1ae9..42bf8b461a0ed6 100644
--- a/tools/perf/arch/powerpc/entry/syscalls/syscall.tbl
+++ b/tools/perf/arch/powerpc/entry/syscalls/syscall.tbl
@@ -18,7 +18,7 @@
8 common creat sys_creat
9 common link sys_link
10 common unlink sys_unlink
-11 nospu execve sys_execve compat_sys_execve
+11 nospu execve sys_execve sys_execve
12 common chdir sys_chdir
13 32 time sys_time32
13 64 time sys_time
@@ -454,7 +454,7 @@
359 common getrandom sys_getrandom
360 common memfd_create sys_memfd_create
361 common bpf sys_bpf
-362 nospu execveat sys_execveat compat_sys_execveat
+362 nospu execveat sys_execveat sys_execveat
363 32 switch_endian sys_ni_syscall
363 64 switch_endian ppc_switch_endian
363 spu switch_endian sys_ni_syscall
diff --git a/tools/perf/arch/s390/entry/syscalls/syscall.tbl b/tools/perf/arch/s390/entry/syscalls/syscall.tbl
index b38d48464368dc..f3c16f2d9746ac 100644
--- a/tools/perf/arch/s390/entry/syscalls/syscall.tbl
+++ b/tools/perf/arch/s390/entry/syscalls/syscall.tbl
@@ -18,7 +18,7 @@
8 common creat sys_creat compat_sys_creat
9 common link sys_link compat_sys_link
10 common unlink sys_unlink compat_sys_unlink
-11 common execve sys_execve compat_sys_execve
+11 common execve sys_execve sys_execve
12 common chdir sys_chdir compat_sys_chdir
13 32 time - compat_sys_time
14 common mknod sys_mknod compat_sys_mknod
@@ -361,7 +361,7 @@
351 common bpf sys_bpf compat_sys_bpf
352 common s390_pci_mmio_write sys_s390_pci_mmio_write compat_sys_s390_pci_mmio_write
353 common s390_pci_mmio_read sys_s390_pci_mmio_read compat_sys_s390_pci_mmio_read
-354 common execveat sys_execveat compat_sys_execveat
+354 common execveat sys_execveat sys_execveat
355 common userfaultfd sys_userfaultfd sys_userfaultfd
356 common membarrier sys_membarrier sys_membarrier
357 common recvmmsg sys_recvmmsg compat_sys_recvmmsg
--
2.26.2
^ permalink raw reply related
* [PATCH 3/6] exec: cleanup the count() function
From: Christoph Hellwig @ 2020-06-15 13:00 UTC (permalink / raw)
To: Al Viro
Cc: linux-arch, linux-s390, Arnd Bergmann, linux-parisc, x86,
linux-mips, linux-kernel, linux-fsdevel, Luis Chamberlain,
sparclinux, linuxppc-dev, linux-arm-kernel
In-Reply-To: <20200615130032.931285-1-hch@lst.de>
Remove the max argument as it is hard wired to MAX_ARG_STRINGS, and
give the function a slightly less generic name.
Signed-off-by: Christoph Hellwig <hch@lst.de>
---
fs/exec.c | 10 +++++-----
1 file changed, 5 insertions(+), 5 deletions(-)
diff --git a/fs/exec.c b/fs/exec.c
index 94107eceda8a67..6e4d9d1ffa35fa 100644
--- a/fs/exec.c
+++ b/fs/exec.c
@@ -411,9 +411,9 @@ get_user_arg_ptr(const char __user *const __user *argv, int nr)
}
/*
- * count() counts the number of strings in array ARGV.
+ * count_strings() counts the number of strings in array ARGV.
*/
-static int count(const char __user *const __user *argv, int max)
+static int count_strings(const char __user *const __user *argv)
{
int i = 0;
@@ -427,7 +427,7 @@ static int count(const char __user *const __user *argv, int max)
if (IS_ERR(p))
return -EFAULT;
- if (i >= max)
+ if (i >= MAX_ARG_STRINGS)
return -E2BIG;
++i;
@@ -445,11 +445,11 @@ static int prepare_arg_pages(struct linux_binprm *bprm,
{
unsigned long limit, ptr_size;
- bprm->argc = count(argv, MAX_ARG_STRINGS);
+ bprm->argc = count_strings(argv);
if (bprm->argc < 0)
return bprm->argc;
- bprm->envc = count(envp, MAX_ARG_STRINGS);
+ bprm->envc = count_strings(envp);
if (bprm->envc < 0)
return bprm->envc;
--
2.26.2
^ permalink raw reply related
* [PATCH 4/6] exec: split prepare_arg_pages
From: Christoph Hellwig @ 2020-06-15 13:00 UTC (permalink / raw)
To: Al Viro
Cc: linux-arch, linux-s390, Arnd Bergmann, linux-parisc, x86,
linux-mips, linux-kernel, linux-fsdevel, Luis Chamberlain,
sparclinux, linuxppc-dev, linux-arm-kernel
In-Reply-To: <20200615130032.931285-1-hch@lst.de>
Move counting the arguments and enviroment variables out of
prepare_arg_pages and rename the rest of the function to check_arg_limit.
This prepares for a version of do_execvat that takes kernel pointers.
Signed-off-by: Christoph Hellwig <hch@lst.de>
---
fs/exec.c | 26 ++++++++++++++------------
1 file changed, 14 insertions(+), 12 deletions(-)
diff --git a/fs/exec.c b/fs/exec.c
index 6e4d9d1ffa35fa..696b1e8180d7d8 100644
--- a/fs/exec.c
+++ b/fs/exec.c
@@ -439,20 +439,10 @@ static int count_strings(const char __user *const __user *argv)
return i;
}
-static int prepare_arg_pages(struct linux_binprm *bprm,
- const char __user *const __user *argv,
- const char __user *const __user *envp)
+static int check_arg_limit(struct linux_binprm *bprm)
{
unsigned long limit, ptr_size;
- bprm->argc = count_strings(argv);
- if (bprm->argc < 0)
- return bprm->argc;
-
- bprm->envc = count_strings(envp);
- if (bprm->envc < 0)
- return bprm->envc;
-
/*
* Limit to 1/4 of the max stack size or 3/4 of _STK_LIM
* (whichever is smaller) for the argv+env strings.
@@ -1890,7 +1880,19 @@ int do_execveat(int fd, struct filename *filename,
if (retval)
goto out_unmark;
- retval = prepare_arg_pages(bprm, argv, envp);
+ bprm->argc = count_strings(argv);
+ if (bprm->argc < 0) {
+ retval = bprm->argc;
+ goto out;
+ }
+
+ bprm->envc = count_strings(envp);
+ if (bprm->envc < 0) {
+ retval = bprm->envc;
+ goto out;
+ }
+
+ retval = check_arg_limit(bprm);
if (retval < 0)
goto out;
--
2.26.2
^ permalink raw reply related
* [PATCH 5/6] exec: add a kernel_execveat helper
From: Christoph Hellwig @ 2020-06-15 13:00 UTC (permalink / raw)
To: Al Viro
Cc: linux-arch, linux-s390, Arnd Bergmann, linux-parisc, x86,
linux-mips, linux-kernel, linux-fsdevel, Luis Chamberlain,
sparclinux, linuxppc-dev, linux-arm-kernel
In-Reply-To: <20200615130032.931285-1-hch@lst.de>
Add a kernel_execveat helper to execute a binary with kernel space argv
and envp pointers. Switch executing init and user mode helpers to this
new helper instead of relying on the implicit set_fs(KERNEL_DS) for early
init code and kernel threads, and move the getname call into the
do_execve helper.
Signed-off-by: Christoph Hellwig <hch@lst.de>
---
fs/exec.c | 116 +++++++++++++++++++++++++++++++---------
include/linux/binfmts.h | 6 +--
init/main.c | 6 +--
kernel/umh.c | 8 ++-
4 files changed, 97 insertions(+), 39 deletions(-)
diff --git a/fs/exec.c b/fs/exec.c
index 696b1e8180d7d8..9e16d56aa53e86 100644
--- a/fs/exec.c
+++ b/fs/exec.c
@@ -439,6 +439,21 @@ static int count_strings(const char __user *const __user *argv)
return i;
}
+static int count_kernel_strings(const char *const *argv)
+{
+ int i;
+
+ if (!argv)
+ return 0;
+
+ for (i = 0; argv[i]; i++) {
+ if (i >= MAX_ARG_STRINGS)
+ return -E2BIG;
+ }
+
+ return i;
+}
+
static int check_arg_limit(struct linux_binprm *bprm)
{
unsigned long limit, ptr_size;
@@ -615,6 +630,19 @@ int copy_string_kernel(const char *arg, struct linux_binprm *bprm)
}
EXPORT_SYMBOL(copy_string_kernel);
+static int copy_strings_kernel(int argc, const char *const *argv,
+ struct linux_binprm *bprm)
+{
+ int ret;
+
+ while (argc-- > 0) {
+ ret = copy_string_kernel(argv[argc], bprm);
+ if (ret)
+ break;
+ }
+ return ret;
+}
+
#ifdef CONFIG_MMU
/*
@@ -1797,9 +1825,11 @@ static int exec_binprm(struct linux_binprm *bprm)
return 0;
}
-int do_execveat(int fd, struct filename *filename,
+static int __do_execveat(int fd, struct filename *filename,
const char __user *const __user *argv,
const char __user *const __user *envp,
+ const char *const *kernel_argv,
+ const char *const *kernel_envp,
int flags, struct file *file)
{
char *pathbuf = NULL;
@@ -1880,16 +1910,30 @@ int do_execveat(int fd, struct filename *filename,
if (retval)
goto out_unmark;
- bprm->argc = count_strings(argv);
- if (bprm->argc < 0) {
- retval = bprm->argc;
- goto out;
- }
+ if (unlikely(kernel_argv)) {
+ bprm->argc = count_kernel_strings(kernel_argv);
+ if (bprm->argc < 0) {
+ retval = bprm->argc;
+ goto out;
+ }
- bprm->envc = count_strings(envp);
- if (bprm->envc < 0) {
- retval = bprm->envc;
- goto out;
+ bprm->envc = count_kernel_strings(kernel_envp);
+ if (bprm->envc < 0) {
+ retval = bprm->envc;
+ goto out;
+ }
+ } else {
+ bprm->argc = count_strings(argv);
+ if (bprm->argc < 0) {
+ retval = bprm->argc;
+ goto out;
+ }
+
+ bprm->envc = count_strings(envp);
+ if (bprm->envc < 0) {
+ retval = bprm->envc;
+ goto out;
+ }
}
retval = check_arg_limit(bprm);
@@ -1906,13 +1950,22 @@ int do_execveat(int fd, struct filename *filename,
goto out;
bprm->exec = bprm->p;
- retval = copy_strings(bprm->envc, envp, bprm);
- if (retval < 0)
- goto out;
- retval = copy_strings(bprm->argc, argv, bprm);
- if (retval < 0)
- goto out;
+ if (unlikely(kernel_argv)) {
+ retval = copy_strings_kernel(bprm->envc, kernel_envp, bprm);
+ if (retval < 0)
+ goto out;
+ retval = copy_strings_kernel(bprm->argc, kernel_argv, bprm);
+ if (retval < 0)
+ goto out;
+ } else {
+ retval = copy_strings(bprm->envc, envp, bprm);
+ if (retval < 0)
+ goto out;
+ retval = copy_strings(bprm->argc, argv, bprm);
+ if (retval < 0)
+ goto out;
+ }
retval = exec_binprm(bprm);
if (retval < 0)
@@ -1963,6 +2016,23 @@ int do_execveat(int fd, struct filename *filename,
return retval;
}
+static int do_execveat(int fd, const char *filename,
+ const char __user *const __user *argv,
+ const char __user *const __user *envp, int flags)
+{
+ int lookup_flags = (flags & AT_EMPTY_PATH) ? LOOKUP_EMPTY : 0;
+ struct filename *name = getname_flags(filename, lookup_flags, NULL);
+
+ return __do_execveat(fd, name, argv, envp, NULL, NULL, flags, NULL);
+}
+
+int kernel_execveat(int fd, const char *filename, const char *const *argv,
+ const char *const *envp, int flags, struct file *file)
+{
+ return __do_execveat(fd, getname_kernel(filename), NULL, NULL, argv,
+ envp, flags, file);
+}
+
void set_binfmt(struct linux_binfmt *new)
{
struct mm_struct *mm = current->mm;
@@ -1992,7 +2062,7 @@ SYSCALL_DEFINE3(execve,
const char __user *const __user *, argv,
const char __user *const __user *, envp)
{
- return do_execveat(AT_FDCWD, getname(filename), argv, envp, 0, NULL);
+ return do_execveat(AT_FDCWD, filename, argv, envp, 0);
}
SYSCALL_DEFINE5(execveat,
@@ -2001,10 +2071,7 @@ SYSCALL_DEFINE5(execveat,
const char __user *const __user *, envp,
int, flags)
{
- int lookup_flags = (flags & AT_EMPTY_PATH) ? LOOKUP_EMPTY : 0;
- struct filename *name = getname_flags(filename, lookup_flags, NULL);
-
- return do_execveat(fd, name, argv, envp, flags, NULL);
+ return do_execveat(fd, filename, argv, envp, flags);
}
/*
@@ -2017,7 +2084,7 @@ COMPAT_SYSCALL_DEFINE3(execve, const char __user *, filename,
const char __user *const __user *, argv,
const char __user *const __user *, envp)
{
- return do_execveat(AT_FDCWD, getname(filename), argv, envp, 0, NULL);
+ return do_execveat(AT_FDCWD, filename, argv, envp, 0);
}
COMPAT_SYSCALL_DEFINE5(execveat, int, fd,
@@ -2026,9 +2093,6 @@ COMPAT_SYSCALL_DEFINE5(execveat, int, fd,
const char __user *const __user *, envp,
int, flags)
{
- int lookup_flags = (flags & AT_EMPTY_PATH) ? LOOKUP_EMPTY : 0;
- struct filename *name = getname_flags(filename, lookup_flags, NULL);
-
- return do_execveat(fd, name, argv, envp, flags, NULL);
+ return do_execveat(fd, filename, argv, envp, flags);
}
#endif /* CONFIG_X86_X32 */
diff --git a/include/linux/binfmts.h b/include/linux/binfmts.h
index bed702e4b1fbd9..1e61c980c16354 100644
--- a/include/linux/binfmts.h
+++ b/include/linux/binfmts.h
@@ -134,9 +134,7 @@ int copy_string_kernel(const char *arg, struct linux_binprm *bprm);
extern void set_binfmt(struct linux_binfmt *new);
extern ssize_t read_code(struct file *, unsigned long, loff_t, size_t);
-int do_execveat(int fd, struct filename *filename,
- const char __user *const __user *__argv,
- const char __user *const __user *__envp,
- int flags, struct file *file);
+int kernel_execveat(int fd, const char *filename, const char *const *argv,
+ const char *const *envp, int flags, struct file *file);
#endif /* _LINUX_BINFMTS_H */
diff --git a/init/main.c b/init/main.c
index 838950ea7bca22..33de235dc2aa00 100644
--- a/init/main.c
+++ b/init/main.c
@@ -1329,10 +1329,8 @@ static int run_init_process(const char *init_filename)
pr_debug(" with environment:\n");
for (p = envp_init; *p; p++)
pr_debug(" %s\n", *p);
- return do_execveat(AT_FDCWD, getname_kernel(init_filename),
- (const char __user *const __user *)argv_init,
- (const char __user *const __user *)envp_init,
- 0, NULL);
+ return kernel_execveat(AT_FDCWD, init_filename, argv_init, envp_init, 0,
+ NULL);
}
static int try_to_run_init_process(const char *init_filename)
diff --git a/kernel/umh.c b/kernel/umh.c
index 7aa9a5817582ca..1284823dbad338 100644
--- a/kernel/umh.c
+++ b/kernel/umh.c
@@ -103,11 +103,9 @@ static int call_usermodehelper_exec_async(void *data)
commit_creds(new);
sub_info->pid = task_pid_nr(current);
- retval = do_execveat(AT_FDCWD,
- sub_info->path ? getname_kernel(sub_info->path) : NULL,
- (const char __user *const __user *)sub_info->argv,
- (const char __user *const __user *)sub_info->envp,
- 0, sub_info->file);
+ retval = kernel_execveat(AT_FDCWD, sub_info->path,
+ (const char *const *)sub_info->argv,
+ (const char *const *)sub_info->envp, 0, sub_info->file);
if (sub_info->file && !retval)
current->flags |= PF_UMH;
out:
--
2.26.2
^ permalink raw reply related
* [PATCH 6/6] kernel: add a kernel_wait helper
From: Christoph Hellwig @ 2020-06-15 13:00 UTC (permalink / raw)
To: Al Viro
Cc: linux-arch, linux-s390, Arnd Bergmann, linux-parisc, x86,
linux-mips, linux-kernel, linux-fsdevel, Luis Chamberlain,
sparclinux, linuxppc-dev, linux-arm-kernel
In-Reply-To: <20200615130032.931285-1-hch@lst.de>
Add a helper that waits for a pid and stores the status in the passed
in kernel pointer. Use it to fix the usage of kernel_wait4 in
call_usermodehelper_exec_sync that only happens to work due to the
implicit set_fs(KERNEL_DS) for kernel threads.
Signed-off-by: Christoph Hellwig <hch@lst.de>
---
include/linux/sched/task.h | 1 +
kernel/exit.c | 16 ++++++++++++++++
kernel/umh.c | 29 ++++-------------------------
3 files changed, 21 insertions(+), 25 deletions(-)
diff --git a/include/linux/sched/task.h b/include/linux/sched/task.h
index 38359071236ad7..a80007df396e95 100644
--- a/include/linux/sched/task.h
+++ b/include/linux/sched/task.h
@@ -102,6 +102,7 @@ struct task_struct *fork_idle(int);
struct mm_struct *copy_init_mm(void);
extern pid_t kernel_thread(int (*fn)(void *), void *arg, unsigned long flags);
extern long kernel_wait4(pid_t, int __user *, int, struct rusage *);
+int kernel_wait(pid_t pid, int *stat);
extern void free_task(struct task_struct *tsk);
diff --git a/kernel/exit.c b/kernel/exit.c
index 727150f2810338..fd598846df0b17 100644
--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -1626,6 +1626,22 @@ long kernel_wait4(pid_t upid, int __user *stat_addr, int options,
return ret;
}
+int kernel_wait(pid_t pid, int *stat)
+{
+ struct wait_opts wo = {
+ .wo_type = PIDTYPE_PID,
+ .wo_pid = find_get_pid(pid),
+ .wo_flags = WEXITED,
+ };
+ int ret;
+
+ ret = do_wait(&wo);
+ if (ret > 0 && wo.wo_stat)
+ *stat = wo.wo_stat;
+ put_pid(wo.wo_pid);
+ return ret;
+}
+
SYSCALL_DEFINE4(wait4, pid_t, upid, int __user *, stat_addr,
int, options, struct rusage __user *, ru)
{
diff --git a/kernel/umh.c b/kernel/umh.c
index 1284823dbad338..6fd948e478bec4 100644
--- a/kernel/umh.c
+++ b/kernel/umh.c
@@ -126,37 +126,16 @@ static void call_usermodehelper_exec_sync(struct subprocess_info *sub_info)
{
pid_t pid;
- /* If SIGCLD is ignored kernel_wait4 won't populate the status. */
+ /* If SIGCLD is ignored do_wait won't populate the status. */
kernel_sigaction(SIGCHLD, SIG_DFL);
pid = kernel_thread(call_usermodehelper_exec_async, sub_info, SIGCHLD);
- if (pid < 0) {
+ if (pid < 0)
sub_info->retval = pid;
- } else {
- int ret = -ECHILD;
- /*
- * Normally it is bogus to call wait4() from in-kernel because
- * wait4() wants to write the exit code to a userspace address.
- * But call_usermodehelper_exec_sync() always runs as kernel
- * thread (workqueue) and put_user() to a kernel address works
- * OK for kernel threads, due to their having an mm_segment_t
- * which spans the entire address space.
- *
- * Thus the __user pointer cast is valid here.
- */
- kernel_wait4(pid, (int __user *)&ret, 0, NULL);
-
- /*
- * If ret is 0, either call_usermodehelper_exec_async failed and
- * the real error code is already in sub_info->retval or
- * sub_info->retval is 0 anyway, so don't mess with it then.
- */
- if (ret)
- sub_info->retval = ret;
- }
+ else
+ kernel_wait(pid, &sub_info->retval);
/* Restore default kernel sig handler */
kernel_sigaction(SIGCHLD, SIG_IGN);
-
umh_complete(sub_info);
}
--
2.26.2
^ permalink raw reply related
* [PATCH] powerpc/ptdump: Fix build failure in hashpagetable.c
From: Christophe Leroy @ 2020-06-15 13:18 UTC (permalink / raw)
To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman
Cc: linuxppc-dev, linux-kernel
H_SUCCESS is only defined when CONFIG_PPC_PSERIES is defined.
!= H_SUCCESS means != 0. Modify the test accordingly.
Reported-by: kernel test robot <lkp@intel.com>
Fixes: 65e701b2d2a8 ("powerpc/ptdump: drop non vital #ifdefs")
Cc: stable@vger.kernel.org
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
arch/powerpc/mm/ptdump/hashpagetable.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/powerpc/mm/ptdump/hashpagetable.c b/arch/powerpc/mm/ptdump/hashpagetable.c
index a2c33efc7ce8..5b8bd34cd3a1 100644
--- a/arch/powerpc/mm/ptdump/hashpagetable.c
+++ b/arch/powerpc/mm/ptdump/hashpagetable.c
@@ -258,7 +258,7 @@ static int pseries_find(unsigned long ea, int psize, bool primary, u64 *v, u64 *
for (i = 0; i < HPTES_PER_GROUP; i += 4, hpte_group += 4) {
lpar_rc = plpar_pte_read_4(0, hpte_group, (void *)ptes);
- if (lpar_rc != H_SUCCESS)
+ if (lpar_rc)
continue;
for (j = 0; j < 4; j++) {
if (HPTE_V_COMPARE(ptes[j].v, want_v) &&
--
2.25.0
^ permalink raw reply related
* Re: [PATCH 3/3] powerpc/8xx: Provide ptep_get() with 16k pages
From: Peter Zijlstra @ 2020-06-15 13:22 UTC (permalink / raw)
To: Christophe Leroy
Cc: linuxppc-dev, linux-kernel, linux-mm, Paul Mackerras,
Andrew Morton, Will Deacon
In-Reply-To: <341688399c1b102756046d19ea6ce39db1ae4742.1592225558.git.christophe.leroy@csgroup.eu>
On Mon, Jun 15, 2020 at 12:57:59PM +0000, Christophe Leroy wrote:
> READ_ONCE() now enforces atomic read, which leads to:
> Fixes: 2ab3a0a02905 ("READ_ONCE: Enforce atomicity for {READ,WRITE}_ONCE() memory accesses")
> Cc: Will Deacon <will@kernel.org>
> Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
> ---
> arch/powerpc/include/asm/nohash/32/pgtable.h | 10 ++++++++++
> 1 file changed, 10 insertions(+)
>
> diff --git a/arch/powerpc/include/asm/nohash/32/pgtable.h b/arch/powerpc/include/asm/nohash/32/pgtable.h
> index b56f14160ae5..77addb599ce7 100644
> --- a/arch/powerpc/include/asm/nohash/32/pgtable.h
> +++ b/arch/powerpc/include/asm/nohash/32/pgtable.h
> @@ -286,6 +286,16 @@ static inline pte_t ptep_get_and_clear(struct mm_struct *mm, unsigned long addr,
> return __pte(pte_update(mm, addr, ptep, ~0, 0, 0));
> }
>
> +#if defined(CONFIG_PPC_8xx) && defined(CONFIG_PPC_16K_PAGES)
> +#define __HAVE_ARCH_PTEP_GET
> +static inline pte_t ptep_get(pte_t *ptep)
> +{
> + pte_t pte = {READ_ONCE(ptep->pte), 0, 0, 0};
> +
> + return pte;
> +}
> +#endif
Would it make sense to have a comment with this magic? The casual reader
might wonder WTH just happened when he stumbles on this :-)
Other than that, the series looks good to me, Thanks!
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
^ permalink raw reply
* Re: properly support exec and wait with kernel pointers
From: Arnd Bergmann @ 2020-06-15 13:42 UTC (permalink / raw)
To: Christoph Hellwig
Cc: linux-arch, linux-s390, Parisc List, the arch/x86 maintainers,
open list:BROADCOM NVRAM DRIVER, linux-kernel@vger.kernel.org,
Linux FS-devel Mailing List, Luis Chamberlain, Al Viro,
sparclinux, linuxppc-dev, Linux ARM
In-Reply-To: <20200615130032.931285-1-hch@lst.de>
On Mon, Jun 15, 2020 at 3:00 PM Christoph Hellwig <hch@lst.de> wrote:
>
> Hi all,
>
> this series first cleans up the exec code and then adds proper
> kernel_execveat and kernel_wait callers instead of relying on the fact
> that the early init code and kernel threads implicitly run with
> the address limit set to KERNEL_DS.
>
> Note that the cleanup removes the compat execve(at) handlers (almost)
> entirely, as we can handle the compat difference very nicely in a
> unified codebase. The only exception is x86 where this would list the
> handlers twice in the same syscall table due to the messed up x32
> design. I had to add an extra compat handler just for that case, but
> maybe someone has a better idea.
I looked at all the patches and I like it a lot. I replied with some suggestions
for x32, but maybe I misunderstood what its problem is, as I don't see
anything preventing us from having two entries in the x32 table pointing
to the same function.
Arnd
^ permalink raw reply
* Re: [PATCH 2/6] exec: simplify the compat syscall handling
From: Arnd Bergmann @ 2020-06-15 13:31 UTC (permalink / raw)
To: Christoph Hellwig
Cc: linux-arch, linux-s390, Parisc List, the arch/x86 maintainers,
open list:BROADCOM NVRAM DRIVER, linux-kernel@vger.kernel.org,
Linux FS-devel Mailing List, Luis Chamberlain, Al Viro,
sparclinux, linuxppc-dev, Linux ARM
In-Reply-To: <20200615130032.931285-3-hch@lst.de>
On Mon, Jun 15, 2020 at 3:00 PM Christoph Hellwig <hch@lst.de> wrote:
>
> The only differenence betweeen the compat exec* syscalls and their
> native versions is that compat_ptr sign extension, and the fact that
> the pointer arithmetics for the two dimensional arrays needs to use
> the compat pointer size. Instead of the compat wrappers and the
> struct user_arg_ptr machinery just use in_compat_syscall() to do the
> right thing for the compat case deep inside get_user_arg_ptr().
>
> Signed-off-by: Christoph Hellwig <hch@lst.de>
Nice!
I have an older patch doing the same for sys_mount() somewhere,
but never got around to send that. One day we should see if we
can just do this for all of them.
> -
> -static const char __user *get_user_arg_ptr(struct user_arg_ptr argv, int nr)
> +static const char __user *
> +get_user_arg_ptr(const char __user *const __user *argv, int nr)
> {
> const char __user *native;
>
> #ifdef CONFIG_COMPAT
> - if (unlikely(argv.is_compat)) {
> + if (in_compat_syscall()) {
> + const compat_uptr_t __user *compat_argv =
> + compat_ptr((unsigned long)argv);
> compat_uptr_t compat;
>
> - if (get_user(compat, argv.ptr.compat + nr))
> + if (get_user(compat, compat_argv + nr))
> return ERR_PTR(-EFAULT);
>
> return compat_ptr(compat);
> }
> #endif
I would expect that the "#ifdef CONFIG_COMPAT" can be removed
now, since compat_ptr() and in_compat_syscall() are now defined
unconditionally. I have not tried that though.
> +/*
> + * x32 syscalls are listed in the same table as x86_64 ones, so we need to
> + * define compat syscalls that are exactly the same as the native version for
> + * the syscall table machinery to work. Sigh..
> + */
> +#ifdef CONFIG_X86_X32
> COMPAT_SYSCALL_DEFINE3(execve, const char __user *, filename,
> - const compat_uptr_t __user *, argv,
> - const compat_uptr_t __user *, envp)
> + const char __user *const __user *, argv,
> + const char __user *const __user *, envp)
> {
> - return do_compat_execve(AT_FDCWD, getname(filename), argv, envp, 0);
> + return do_execveat(AT_FDCWD, getname(filename), argv, envp, 0, NULL);
> }
Maybe move it to arch/x86/kernel/process_64.c or arch/x86/entry/syscall_x32.c
to keep it out of the common code if this is needed. I don't really understand
the comment, why can't this just use this?
--- a/arch/x86/entry/syscalls/syscall_64.tbl
+++ b/arch/x86/entry/syscalls/syscall_64.tbl
@@ -379,7 +379,7 @@
517 x32 recvfrom compat_sys_recvfrom
518 x32 sendmsg compat_sys_sendmsg
519 x32 recvmsg compat_sys_recvmsg
-520 x32 execve compat_sys_execve
+520 x32 execve sys_execve
521 x32 ptrace compat_sys_ptrace
522 x32 rt_sigpending compat_sys_rt_sigpending
523 x32 rt_sigtimedwait compat_sys_rt_sigtimedwait_time64
@@ -404,7 +404,7 @@
542 x32 getsockopt compat_sys_getsockopt
543 x32 io_setup compat_sys_io_setup
544 x32 io_submit compat_sys_io_submit
-545 x32 execveat compat_sys_execveat
+545 x32 execveat sys_execveat
546 x32 preadv2 compat_sys_preadv64v2
547 x32 pwritev2 compat_sys_pwritev64v2
548 x32 process_madvise compat_sys_process_madvise
Arnd
^ permalink raw reply
* Re: [PATCH 0/8 v2] PCI: Align return values of PCIe capability and PCI accessors
From: Jason Gunthorpe @ 2020-06-15 13:46 UTC (permalink / raw)
To: refactormyself
Cc: Don Brace, Sam Bobroff, Mike Marciniszyn, linux-scsi,
Martin K. Petersen, linux-rdma, linux-pci, Dennis Dalessandro,
esc.storagedev, Doug Ledford, linux-kernel, dmaengine, Vinod Koul,
helgaas, skhan, bjorn, Oliver O'Halloran, linuxppc-dev,
James E.J. Bottomley, linux-kernel-mentees
In-Reply-To: <20200615073225.24061-1-refactormyself@gmail.com>
On Mon, Jun 15, 2020 at 09:32:17AM +0200, refactormyself@gmail.com wrote:
> From: Bolarinwa Olayemi Saheed <refactormyself@gmail.com>
>
>
> PATCH 1/8 to 7/8:
> PCIBIOS_ error codes have positive values and they are passed down the
> call heirarchy from accessors. For functions which are meant to return
> only a negative value on failure, passing on this value is a bug.
> To mitigate this, call pcibios_err_to_errno() before passing on return
> value from PCIe capability accessors call heirarchy. This function
> converts any positive PCIBIOS_ error codes to negative generic error
> values.
>
> PATCH 8/8:
> The PCIe capability accessors can return 0, -EINVAL, or any PCIBIOS_ error
> code. The pci accessor on the other hand can only return 0 or any PCIBIOS_
> error code.This inconsistency among these accessor makes it harder for
> callers to check for errors.
> Return PCIBIOS_BAD_REGISTER_NUMBER instead of -EINVAL in all PCIe
> capability accessors.
>
> MERGING:
> These may all be merged via the PCI tree, since it is a collection of
> similar fixes. This way they all get merged at once.
I prefer this not happen for active trees, it just risks needless
merge conflicts.
I will take the hfi1 patches at least, let me know when they are
reviewed
Thanks,
Jason
^ permalink raw reply
* Re: [PATCH 2/6] exec: simplify the compat syscall handling
From: Christoph Hellwig @ 2020-06-15 14:12 UTC (permalink / raw)
To: Arnd Bergmann
Cc: linux-arch, linux-s390, Parisc List, the arch/x86 maintainers,
open list:BROADCOM NVRAM DRIVER, linux-kernel@vger.kernel.org,
Linux FS-devel Mailing List, Luis Chamberlain, Al Viro,
sparclinux, linuxppc-dev, Christoph Hellwig, Linux ARM
In-Reply-To: <CAK8P3a0bRD3RzE_X6Tjzu9Tj+OhHhP+S=k6+VYODBGko8oQhew@mail.gmail.com>
On Mon, Jun 15, 2020 at 03:31:35PM +0200, Arnd Bergmann wrote:
> > #ifdef CONFIG_COMPAT
> > - if (unlikely(argv.is_compat)) {
> > + if (in_compat_syscall()) {
> > + const compat_uptr_t __user *compat_argv =
> > + compat_ptr((unsigned long)argv);
> > compat_uptr_t compat;
> >
> > - if (get_user(compat, argv.ptr.compat + nr))
> > + if (get_user(compat, compat_argv + nr))
> > return ERR_PTR(-EFAULT);
> >
> > return compat_ptr(compat);
> > }
> > #endif
>
> I would expect that the "#ifdef CONFIG_COMPAT" can be removed
> now, since compat_ptr() and in_compat_syscall() are now defined
> unconditionally. I have not tried that though.
True, I'll give it a spin.
> > +/*
> > + * x32 syscalls are listed in the same table as x86_64 ones, so we need to
> > + * define compat syscalls that are exactly the same as the native version for
> > + * the syscall table machinery to work. Sigh..
> > + */
> > +#ifdef CONFIG_X86_X32
> > COMPAT_SYSCALL_DEFINE3(execve, const char __user *, filename,
> > - const compat_uptr_t __user *, argv,
> > - const compat_uptr_t __user *, envp)
> > + const char __user *const __user *, argv,
> > + const char __user *const __user *, envp)
> > {
> > - return do_compat_execve(AT_FDCWD, getname(filename), argv, envp, 0);
> > + return do_execveat(AT_FDCWD, getname(filename), argv, envp, 0, NULL);
> > }
>
> Maybe move it to arch/x86/kernel/process_64.c or arch/x86/entry/syscall_x32.c
> to keep it out of the common code if this is needed.
I'd rather keep it in common code as that allows all the low-level
exec stuff to be marked static, and avoid us growing new pointless
compat variants through copy and paste.
smart compiler to d
> I don't really understand
> the comment, why can't this just use this?
That errors out with:
ld: arch/x86/entry/syscall_x32.o:(.rodata+0x1040): undefined reference to
`__x32_sys_execve'
ld: arch/x86/entry/syscall_x32.o:(.rodata+0x1108): undefined reference to
`__x32_sys_execveat'
make: *** [Makefile:1139: vmlinux] Error 1
^ permalink raw reply
* Re: [PATCH 2/6] exec: simplify the compat syscall handling
From: Christoph Hellwig @ 2020-06-15 14:43 UTC (permalink / raw)
To: Arnd Bergmann
Cc: linux-arch, linux-s390, Parisc List, the arch/x86 maintainers,
open list:BROADCOM NVRAM DRIVER, linux-kernel@vger.kernel.org,
Linux FS-devel Mailing List, Luis Chamberlain, Al Viro,
sparclinux, linuxppc-dev, Christoph Hellwig, Linux ARM
In-Reply-To: <CAK8P3a2MeZhayZWkPbd4Ckq3n410p_n808NJTwN=JjzqHRiAXg@mail.gmail.com>
On Mon, Jun 15, 2020 at 04:40:28PM +0200, Arnd Bergmann wrote:
> > ld: arch/x86/entry/syscall_x32.o:(.rodata+0x1040): undefined reference to
> > `__x32_sys_execve'
> > ld: arch/x86/entry/syscall_x32.o:(.rodata+0x1108): undefined reference to
> > `__x32_sys_execveat'
> > make: *** [Makefile:1139: vmlinux] Error 1
>
> Ah, I see: it's marked x32-only, so arch/x86/entry/syscall_x32.c
> uses the __x32 prefix instead of the __x64 one. Marking it 'common'
> instead would make it work, but also create an extra entry point
> for native processes, something that commit
> 6365b842aae4 ("x86/syscalls: Split the x32 syscalls into their own table")
> was trying to avoid.
Marking it common also doesn't compile at all because __NR_execve
and __NR_execveat get redefined in unistd_64.h. I then tried to rename
the x32 versions, which failed in yet another way. At that point I gave
up instead of digging myself into a deeper hole..
^ permalink raw reply
* Re: [PATCH 2/6] exec: simplify the compat syscall handling
From: Arnd Bergmann @ 2020-06-15 14:40 UTC (permalink / raw)
To: Christoph Hellwig
Cc: linux-arch, linux-s390, Parisc List, the arch/x86 maintainers,
open list:BROADCOM NVRAM DRIVER, linux-kernel@vger.kernel.org,
Linux FS-devel Mailing List, Luis Chamberlain, Al Viro,
sparclinux, linuxppc-dev, Linux ARM
In-Reply-To: <20200615141239.GA12951@lst.de>
On Mon, Jun 15, 2020 at 4:12 PM Christoph Hellwig <hch@lst.de> wrote:
> On Mon, Jun 15, 2020 at 03:31:35PM +0200, Arnd Bergmann wrote:
>
> > I don't really understand
> > the comment, why can't this just use this?
>
> That errors out with:
>
> ld: arch/x86/entry/syscall_x32.o:(.rodata+0x1040): undefined reference to
> `__x32_sys_execve'
> ld: arch/x86/entry/syscall_x32.o:(.rodata+0x1108): undefined reference to
> `__x32_sys_execveat'
> make: *** [Makefile:1139: vmlinux] Error 1
Ah, I see: it's marked x32-only, so arch/x86/entry/syscall_x32.c
uses the __x32 prefix instead of the __x64 one. Marking it 'common'
instead would make it work, but also create an extra entry point
for native processes, something that commit
6365b842aae4 ("x86/syscalls: Split the x32 syscalls into their own table")
was trying to avoid.
Arnd
^ permalink raw reply
* Re: [PATCH 2/6] exec: simplify the compat syscall handling
From: Arnd Bergmann @ 2020-06-15 14:46 UTC (permalink / raw)
To: Christoph Hellwig
Cc: linux-arch, linux-s390, Parisc List, the arch/x86 maintainers,
open list:BROADCOM NVRAM DRIVER, linux-kernel@vger.kernel.org,
Linux FS-devel Mailing List, Luis Chamberlain, Al Viro,
sparclinux, linuxppc-dev, Linux ARM
In-Reply-To: <20200615144310.GA15101@lst.de>
On Mon, Jun 15, 2020 at 4:43 PM Christoph Hellwig <hch@lst.de> wrote:
>
> On Mon, Jun 15, 2020 at 04:40:28PM +0200, Arnd Bergmann wrote:
> > > ld: arch/x86/entry/syscall_x32.o:(.rodata+0x1040): undefined reference to
> > > `__x32_sys_execve'
> > > ld: arch/x86/entry/syscall_x32.o:(.rodata+0x1108): undefined reference to
> > > `__x32_sys_execveat'
> > > make: *** [Makefile:1139: vmlinux] Error 1
> >
> > Ah, I see: it's marked x32-only, so arch/x86/entry/syscall_x32.c
> > uses the __x32 prefix instead of the __x64 one. Marking it 'common'
> > instead would make it work, but also create an extra entry point
> > for native processes, something that commit
> > 6365b842aae4 ("x86/syscalls: Split the x32 syscalls into their own table")
> > was trying to avoid.
>
> Marking it common also doesn't compile at all because __NR_execve
> and __NR_execveat get redefined in unistd_64.h. I then tried to rename
> the x32 versions, which failed in yet another way. At that point I gave
> up instead of digging myself into a deeper hole..
How about this one:
diff --git a/arch/x86/entry/syscall_x32.c b/arch/x86/entry/syscall_x32.c
index 3d8d70d3896c..0ce15807cf54 100644
--- a/arch/x86/entry/syscall_x32.c
+++ b/arch/x86/entry/syscall_x32.c
@@ -16,6 +16,9 @@
#undef __SYSCALL_X32
#undef __SYSCALL_COMMON
+#define __x32_sys_execve __x64_sys_execve
+#define __x32_sys_execveat __x64_sys_execveat
+
#define __SYSCALL_X32(nr, sym) [nr] = __x32_##sym,
#define __SYSCALL_COMMON(nr, sym) [nr] = __x64_##sym,
Still ugly, but much simpler and more localized (if it works).
Arnd
^ permalink raw reply related
* Re: [PATCH 2/6] exec: simplify the compat syscall handling
From: Brian Gerst @ 2020-06-15 14:48 UTC (permalink / raw)
To: Christoph Hellwig
Cc: linux-arch, linux-s390, Parisc List, Arnd Bergmann,
the arch/x86 maintainers, open list:BROADCOM NVRAM DRIVER,
linux-kernel@vger.kernel.org, Linux FS-devel Mailing List,
Luis Chamberlain, Al Viro, sparclinux, linuxppc-dev, Linux ARM
In-Reply-To: <20200615141239.GA12951@lst.de>
On Mon, Jun 15, 2020 at 10:13 AM Christoph Hellwig <hch@lst.de> wrote:
>
> On Mon, Jun 15, 2020 at 03:31:35PM +0200, Arnd Bergmann wrote:
> > > #ifdef CONFIG_COMPAT
> > > - if (unlikely(argv.is_compat)) {
> > > + if (in_compat_syscall()) {
> > > + const compat_uptr_t __user *compat_argv =
> > > + compat_ptr((unsigned long)argv);
> > > compat_uptr_t compat;
> > >
> > > - if (get_user(compat, argv.ptr.compat + nr))
> > > + if (get_user(compat, compat_argv + nr))
> > > return ERR_PTR(-EFAULT);
> > >
> > > return compat_ptr(compat);
> > > }
> > > #endif
> >
> > I would expect that the "#ifdef CONFIG_COMPAT" can be removed
> > now, since compat_ptr() and in_compat_syscall() are now defined
> > unconditionally. I have not tried that though.
>
> True, I'll give it a spin.
>
> > > +/*
> > > + * x32 syscalls are listed in the same table as x86_64 ones, so we need to
> > > + * define compat syscalls that are exactly the same as the native version for
> > > + * the syscall table machinery to work. Sigh..
> > > + */
> > > +#ifdef CONFIG_X86_X32
> > > COMPAT_SYSCALL_DEFINE3(execve, const char __user *, filename,
> > > - const compat_uptr_t __user *, argv,
> > > - const compat_uptr_t __user *, envp)
> > > + const char __user *const __user *, argv,
> > > + const char __user *const __user *, envp)
> > > {
> > > - return do_compat_execve(AT_FDCWD, getname(filename), argv, envp, 0);
> > > + return do_execveat(AT_FDCWD, getname(filename), argv, envp, 0, NULL);
> > > }
> >
> > Maybe move it to arch/x86/kernel/process_64.c or arch/x86/entry/syscall_x32.c
> > to keep it out of the common code if this is needed.
>
> I'd rather keep it in common code as that allows all the low-level
> exec stuff to be marked static, and avoid us growing new pointless
> compat variants through copy and paste.
> smart compiler to d
>
> > I don't really understand
> > the comment, why can't this just use this?
>
> That errors out with:
>
> ld: arch/x86/entry/syscall_x32.o:(.rodata+0x1040): undefined reference to
> `__x32_sys_execve'
> ld: arch/x86/entry/syscall_x32.o:(.rodata+0x1108): undefined reference to
> `__x32_sys_execveat'
> make: *** [Makefile:1139: vmlinux] Error 1
I think I have a fix for this, by modifying the syscall wrappers to
add an alias for the __x32 variant to the native __x64_sys_foo().
I'll get back to you with a patch.
--
Brian Gerst
^ permalink raw reply
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