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Fri, 28 Aug 2026 11:04:21 +0000 (GMT) Received: from smtpav01.fra02v.mail.ibm.com (smtpav01.fra02v.mail.ibm.com [10.20.54.100]) by smtprelay03.fra02v.mail.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 67SB4Hnb36372800 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 28 Aug 2026 11:04:17 GMT Received: from smtpav01.fra02v.mail.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id E7FDC20043; Fri, 28 Aug 2026 11:04:16 +0000 (GMT) Received: from smtpav01.fra02v.mail.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id A528720040; Fri, 28 Aug 2026 11:04:10 +0000 (GMT) Received: from [9.61.249.126] (unknown [9.61.249.126]) by smtpav01.fra02v.mail.ibm.com (Postfix) with ESMTPS; Fri, 28 Aug 2026 11:04:10 +0000 (GMT) Content-Type: multipart/alternative; boundary="------------CYnNj7x7LOdPK0GMFZH5FtBY" Message-ID: <94a8cd96-9e49-4f39-8730-e677b113d256@linux.ibm.com> Date: Fri, 28 Aug 2026 16:34:07 +0530 X-Mailing-List: linuxppc-dev@lists.ozlabs.org List-Id: List-Help: List-Owner: List-Post: List-Archive: , List-Subscribe: , , List-Unsubscribe: Precedence: list MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH 6/8] pseries/plpks: add HCALLs for PKWM wrapping key life cycle management To: Srish Srinivasan , linux-integrity@vger.kernel.org, keyrings@vger.kernel.org, linuxppc-dev@lists.ozlabs.org Cc: maddy@linux.ibm.com, mpe@ellerman.id.au, npiggin@gmail.com, christophe.leroy@csgroup.eu, James.Bottomley@HansenPartnership.com, jarkko@kernel.org, zohar@linux.ibm.com, linux-kernel@vger.kernel.org, linux-security-module@vger.kernel.org, nayna@linux.ibm.com References: <20260827062309.724808-1-ssrish@linux.ibm.com> <20260827062309.724808-7-ssrish@linux.ibm.com> Content-Language: en-US From: R Nageswara Sastry In-Reply-To: <20260827062309.724808-7-ssrish@linux.ibm.com> X-TM-AS-GCONF: 00 X-Proofpoint-Reinject: loops=2 maxloops=12 X-Proofpoint-GUID: LOBLOieNQ4cbdVa3cGrkJB9Gb3WEDlKw X-Proofpoint-ORIG-GUID: VZPLiJkppqy7fbbuhBvfF05sGoP8Gups X-Proofpoint-Spam-Details-Enc: AW1haW4tMjYwODI4MDA5NSBTYWx0ZWRfXyKSdzQ3KHYog p66qkRA03Qf+cmT07gS3U42SPNIjEakNcbrCVlY8QoEyQK2W3U9QmLu+OmZ4yxlrb02mn1VUUFd ZUYL8PTEp6jB44C8gKYKIrkskBPiow2D4iNjU+Y41KGBmJ5Ril3DoaeNvg4pq/Y2geXpjHVlLHF zWhVqbZmbaKflvSU3424ngrl2Me0dTmWjJTNWYxWBKalFvUlC6zjHX2G6FVqAEMK6OL2I7CiAh7 YyzZrQJ/7Mm0PTw5vcsKA6wyfqxP5T61jJ6vDsoCcAQmXt0FmLmh5Tk5uWbX7jzt6b2Wwdcmyoo ZLfXQvfc6dJt5QWPJ8c6u7EXV18hhg0k0nDZnyRn8jzeQgn8s4g+TMYLDXGJjIS2oQob0cSUdw5 cdUkPPIWnlSIa3qFUl0h4z5i3q32vvB1v7YTM9UOVi6glwUT6yZ/BHJtLC8v+UotZZUNdUt3k58 4f4EmbbghTJB5QpEXkw== X-Authority-Analysis: v=2.4 cv=QsRuG1yd c=1 sm=1 tr=0 ts=6a916b37 cx=c_pps a=GFwsV6G8L6GxiO2Y/PsHdQ==:117 a=GFwsV6G8L6GxiO2Y/PsHdQ==:17 a=Sv0fKeRqtYgA:10 a=VkNPw1HP01LnGYTKEx00:22 a=RnoormkPH1_aCDwRdu11:22 a=uAbxVGIbfxUO_5tXvNgY:22 a=r77TgQKjGQsHNAKrUKIA:9 a=VnNF1IyMAAAA:8 a=syZUe3wMas8Yd6IghWgA:9 a=2zeZwfwtEwIPCJIq:21 a=QEXdDO2ut3YA:10 a=lWQKvBrNlG38MY5WF7oA:9 a=YlH5uDmbomUVZx3t:21 a=_W_S_7VecoQA:10 a=lqcHg5cX4UMA:10 a=3ZKOabzyN94A:10 X-Proofpoint-Spam-Info: AW1haW4tMjYwODI4MDA5NSBTYWx0ZWRfX77ndFCbU0mSV pgM0YvbTEfpu12jBEBcYFCpqn4cpzyeETJXxef1dak1u+cExxpw6sRLOKcO3FQXHcnt7Znf0UTo kEtA9Yn3HQSxqjOOBlDLWWBjP57F4io= X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1176,Hydra:6.1.134,FMLib:17.12.100.49 definitions=2026-08-28_03,2026-08-27_02,2025-10-01_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 malwarescore=0 adultscore=0 suspectscore=0 priorityscore=1501 impostorscore=0 spamscore=0 lowpriorityscore=0 clxscore=1011 bulkscore=0 phishscore=0 classifier=typeunknown authscore=0 authtc= authcc= route=outbound adjust=0 reason=mlx scancount=1 engine=8.22.0-2606150000 definitions=main-2608280095 This is a multi-part message in MIME format. --------------CYnNj7x7LOdPK0GMFZH5FtBY Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 27.08.2026 11:53 AM, Srish Srinivasan wrote: > The PKWM trusted source uses a single wrapping key per LPAR, created only > once during trust source initialization. All the wrap and unwrap requests > are bound to this default wrapping key. > > Implement H_PKS_REVOKE_OBJECT, H_PKS_UNREVOKE_OBJECT, and > H_PKS_GET_OBJECTLABELS HCALLs to enable support for revoking and unrevoking > PKWM wrapping keys, and for retrieving wrapping key labels. The label > retrieval operation (H_PKS_GET_OBJECTLABELS) applies to all wrapping keys > including the default one, while the life cycle operations > (H_PKS_REVOKE_OBJECT/H_PKS_UNREVOKE_OBJECT) apply only to user-created > wrapping keys. > > Signed-off-by: Srish Srinivasan > --- > Documentation/arch/powerpc/papr_hcalls.rst | 33 ++ > arch/powerpc/include/asm/hvcall.h | 5 +- > arch/powerpc/include/asm/plpks.h | 15 + > arch/powerpc/platforms/pseries/plpks.c | 475 ++++++++++++++++++++- > 4 files changed, 524 insertions(+), 4 deletions(-) > > diff --git a/Documentation/arch/powerpc/papr_hcalls.rst b/Documentation/arch/powerpc/papr_hcalls.rst > index 44c9c8b32ae3..3455b403a048 100644 > --- a/Documentation/arch/powerpc/papr_hcalls.rst > +++ b/Documentation/arch/powerpc/papr_hcalls.rst > @@ -343,6 +343,39 @@ is returned to the caller. > H_PKS_UNWRAP_OBJECT is used to unwrap an object that was previously wrapped with > H_PKS_WRAP_OBJECT. > > +**H_PKS_REVOKE_OBJECT** > + > +| Input: authorization, objectlabel, objectlabellen, flags > +| Out: *object policy* > +| Return Value: *H_Success, H_Function, H_State, H_Parameter, H_P2, H_P3, H_P4, > + H_Authority, H_Not_Found, H_Busy, H_Aborted* > + > +H_PKS_REVOKE_OBJECT is used to revoke an object in Platform Keystore. > + > + > +**H_PKS_UNREVOKE_OBJECT** > + > +| Input: authorization, objectlabel, objectlabellen, flags > +| Out: *object policy* > +| Return Value: *H_Success, H_Function, H_State, H_Parameter, H_P2, H_P3, H_P4, > + H_Authority, H_Not_Found, H_Busy, H_Aborted* > + > +H_PKS_UNREVOKE_OBJECT is used to unrevoke an object that was previously revoked > +with H_PKS_REVOKE_OBJECT in Platform Keystore. > + > + > +**H_PKS_GET_OBJECTLABELS** > + > +| Input: authorization, continueToken, out, outlen > +| Out: *continue-token, number of object labels in the returned list, object > + label list* > +| Return Value: *H_Success, H_Function, H_State, H_Parameter, H_P2, H_P3, H_P4, > + H_Authority, H_Busy, H_Aborted, H_Continue* > + > +H_PKS_GET_OBJECTLABELS is used to retrieve a list of object labels owned by the > +specified consumer. > + > + > References > ========== > .. [1] "Power Architecture Platform Reference" > diff --git a/arch/powerpc/include/asm/hvcall.h b/arch/powerpc/include/asm/hvcall.h > index dff90a7d7f70..4d4c2ce1dd87 100644 > --- a/arch/powerpc/include/asm/hvcall.h > +++ b/arch/powerpc/include/asm/hvcall.h > @@ -340,6 +340,7 @@ > #define H_PKS_GET_CONFIG 0x41C > #define H_PKS_SET_PASSWORD 0x420 > #define H_PKS_GEN_PASSWORD 0x424 > +#define H_PKS_GET_OBJECTLABELS 0x428 > #define H_PKS_WRITE_OBJECT 0x42C > #define H_PKS_GEN_KEY 0x430 > #define H_PKS_READ_OBJECT 0x434 > @@ -362,7 +363,9 @@ > #define H_GUEST_DELETE 0x488 > #define H_PKS_WRAP_OBJECT 0x490 > #define H_PKS_UNWRAP_OBJECT 0x494 > -#define MAX_HCALL_OPCODE H_PKS_UNWRAP_OBJECT > +#define H_PKS_REVOKE_OBJECT 0x4AC > +#define H_PKS_UNREVOKE_OBJECT 0x4B0 > +#define MAX_HCALL_OPCODE H_PKS_UNREVOKE_OBJECT > > /* Scope args for H_SCM_UNBIND_ALL */ > #define H_UNBIND_SCOPE_ALL (0x1) > diff --git a/arch/powerpc/include/asm/plpks.h b/arch/powerpc/include/asm/plpks.h > index 8b2ffb27db5a..c39d1f07017e 100644 > --- a/arch/powerpc/include/asm/plpks.h > +++ b/arch/powerpc/include/asm/plpks.h > @@ -25,6 +25,7 @@ > #define PLPKS_SIGNEDUPDATE PPC_BIT32(7) // Object can only be modified by signed updates > #define PLPKS_WRAPPINGKEY PPC_BIT32(8) // Object contains a wrapping key > #define PLPKS_HVPROVISIONED PPC_BIT32(28) // Hypervisor has provisioned this object > +#define PLPKS_REVOKED PPC_BIT32(30) // Object is revoked > > // Signature algorithm flags from signed_update_algorithms > #define PLPKS_ALG_RSA2048 PPC_BIT(0) > @@ -123,6 +124,20 @@ int plpks_wrap_object(u8 **input_buf, u64 input_len, u16 wrap_flags, > > int plpks_unwrap_object(u8 **input_buf, u64 input_len, > u8 **output_buf, u64 *output_len); > + > +int plpks_revoke_wrapping_key(struct plpks_var *var); > + > +int plpks_unrevoke_wrapping_key(struct plpks_var *var); > + > +int plpks_del_wrapping_key(struct plpks_var *var); > + > +int plpks_is_wrapping_key_revoked(struct plpks_var *var); > + > +int plpks_get_object_labels(u8 **output_buf, u64 *output_len, > + char *comp_prefix); > + > +bool plpks_revoke_is_supported(void); > + > #else // CONFIG_PSERIES_PLPKS > static inline bool plpks_is_available(void) { return false; } > static inline u16 plpks_get_passwordlen(void) { BUILD_BUG(); } > diff --git a/arch/powerpc/platforms/pseries/plpks.c b/arch/powerpc/platforms/pseries/plpks.c > index b553f7b130b6..48a86497eb2b 100644 > --- a/arch/powerpc/platforms/pseries/plpks.c > +++ b/arch/powerpc/platforms/pseries/plpks.c > @@ -23,8 +23,17 @@ > */ > #define PLPKS_WRAPPING_BUF_DIFF 1024 > > +/* > + * Maximum length for the buffer to store the retrieved object labels > + */ > +#define PLPKS_OBJLABEL_BUF_MAX 2550 > + > +#define PLPKS_OBJLABEL_LEN_FIELD_SIZE 2 > +#define PLPKS_OBJLABEL_PREFIX_LEN 8 > + > #define PLPKS_WRAP_INTERFACE_BIT 3 > #define PLPKS_WRAPPING_KEY_LENGTH 32 > +#define PLPKS_REVOKE_INTERFACE_BIT 4 > > #define WRAPFLAG_BE_BIT_SET(be_bit) \ > BIT_ULL(63 - (be_bit)) > @@ -46,6 +55,7 @@ > #include > #include > #include > +#include > #include > #include > #include > @@ -67,6 +77,7 @@ static u32 maxlargeobjectsize; > static u64 signedupdatealgorithms; > static u64 wrappingfeatures; > static bool wrapsupport; > +static bool revokesupport; > > struct plpks_auth { > u8 version; > @@ -146,6 +157,9 @@ static int pseries_status_to_err(int rc) > case H_ABORTED: > err = -EIO; > break; > + case H_CONTINUE: > + err = -EAGAIN; > + break; > default: > err = -EINVAL; > } > @@ -312,6 +326,7 @@ static int _plpks_get_config(void) > signedupdatealgorithms = be64_to_cpu(config->signedupdatealgorithms); > wrappingfeatures = be64_to_cpu(config->wrappingfeatures); > wrapsupport = config->flags & PPC_BIT8(PLPKS_WRAP_INTERFACE_BIT); > + revokesupport = config->flags & PPC_BIT8(PLPKS_REVOKE_INTERFACE_BIT); > > // Validate that the numbers we get back match the requirements of the spec > if (maxpwsize < 32) { > @@ -831,9 +846,6 @@ static int plpks_read_var(u8 consumer, struct plpks_var *var) > if (var->namelen > PLPKS_MAX_NAME_SIZE) > return -EINVAL; > > - if (var->policy & PLPKS_WRAPPINGKEY) > - return -EPERM; > - > auth = construct_auth(consumer); > if (IS_ERR(auth)) > return PTR_ERR(auth); > @@ -903,6 +915,23 @@ bool plpks_wrapping_is_supported(void) > } > EXPORT_SYMBOL_GPL(plpks_wrapping_is_supported); > > +/** > + * plpks_revoke_is_supported() - Get the H_PKS_REVOKE_OBJECT and > + * H_PKS_UNREVOKE_OBJECT interfaces availability status for the LPAR. > + * > + * Successful execution of the H_PKS_GET_CONFIG HCALL during initialization > + * sets bit 4 of the flags variable in the PLPKS config structure if the > + * H_PKS_REVOKE_OBJECT and H_PKS_UNREVOKE_OBJECT interfaces are supported. > + * > + * Returns: true if the H_PKS_REVOKE_OBJECT and H_PKS_UNREVOKE_OBJECT interfaces > + * are supported, false if not. > + */ > +bool plpks_revoke_is_supported(void) > +{ > + return revokesupport; > +} > +EXPORT_SYMBOL_GPL(plpks_revoke_is_supported); > + > /** > * plpks_gen_wrapping_key() - Generate a new random key with the 'wrapping key' > * policy set. > @@ -1189,6 +1218,446 @@ int plpks_unwrap_object(u8 **input_buf, u64 input_len, u8 **output_buf, > } > EXPORT_SYMBOL_GPL(plpks_unwrap_object); > > +/** > + * plpks_revoke_wrapping_key() - Revoke a wrapping key stored in the PLPKS. > + * @var: variable representing the wrapping key to be revoked > + * > + * The H_PKS_REVOKE_OBJECT HCALL revokes an object stored in the PLPKS. > + * > + * Possible reasons for the returned errno values: > + * > + * -ENXIO if PLPKS is not supported > + * -EIO if PLPKS access is blocked due to the LPAR's state > + * if PLPKS modification is blocked due to the LPAR's state > + * if an error occurred while processing the request > + * -EINVAL if invalid authorization parameter > + * if invalid wrapping key label parameter > + * if invalid wrapping key label length parameter > + * if invalid or unsupported wrapping key revoking flags > + * -EPERM if access is denied > + * -ENOENT if the requested wrapping key was not found > + * -EBUSY if unable to handle the request or long running operation > + * initiated, retry later. > + * > + * Returns: On success 0 is returned, a negative errno if not. > + */ > +int plpks_revoke_wrapping_key(struct plpks_var *var) > +{ > + unsigned long retbuf[PLPAR_HCALL_BUFSIZE] = { 0 }; > + struct plpks_auth *auth = NULL; > + struct label *label; > + u64 objrevokeflags = 0; > + int rc = 0, pseries_status = 0; > + > + if (!var->name || !*var->name) { Can you please add null check for 'var' also. if (! var || !var->name || !*var->name) > + pr_err("key label cannot be NULL/empty\n"); > + rc = -EINVAL; > + goto out; > + } > + > + if (!strcmp((char *)var->name, PLPKS_DEFAULT_WRAPKEY_LABEL)) { > + pr_warn("the default wrapping key must not be revoked!\n"); > + rc = -EPERM; > + goto out; > + } > + > + auth = construct_auth(PLPKS_OS_OWNER); > + if (IS_ERR(auth)) { > + rc = PTR_ERR(auth); > + goto out; > + } > + > + label = construct_label(var->component, var->os, var->name, > + var->namelen); > + if (IS_ERR(label)) { > + rc = PTR_ERR(label); > + goto out; > + } > + > + rc = plpar_hcall(H_PKS_REVOKE_OBJECT, retbuf, virt_to_phys(auth), > + virt_to_phys(label), label->size, objrevokeflags); > + > + pseries_status = rc; > + rc = pseries_status_to_err(rc); > + > + if (rc) { > + pr_err("H_PKS_REVOKE_OBJECT failed. pseries_status=%d, rc=%d\n", > + pseries_status, rc); > + } > + > + if (!rc || (rc == -EPERM && retbuf[0])) > + var->policy = (u32)retbuf[0]; > + > + kfree(label); > +out: > + kfree(auth); > + return rc; > +} > +EXPORT_SYMBOL_GPL(plpks_revoke_wrapping_key); > + > +/** > + * plpks_unrevoke_wrapping_key() - Unrevoke a revoked wrapping key in the PLPKS. > + * @var: variable representing the revoked wrapping key to be unrevoked > + * > + * The H_PKS_UNREVOKE_OBJECT HCALL unrevokes a revoked object stored in the > + * PLPKS. > + * > + * Possible reasons for the returned errno values: > + * > + * -ENXIO if PLPKS is not supported > + * -EIO if PLPKS access is blocked due to the LPAR's state > + * if PLPKS modification is blocked due to the LPAR's state > + * if an error occurred while processing the request > + * -EINVAL if invalid authorization parameter > + * if invalid object label parameter > + * if invalid object label length parameter > + * if invalid or unsupported object revoking flags > + * -EPERM if access is denied > + * -ENOENT if the requested object was not found > + * -EBUSY if unable to handle the request or long running operation > + * initiated, retry later. > + * > + * Returns: On success 0 is returned, a negative errno if not. > + */ > +int plpks_unrevoke_wrapping_key(struct plpks_var *var) > +{ > + unsigned long retbuf[PLPAR_HCALL_BUFSIZE] = { 0 }; > + struct plpks_auth *auth = NULL; > + struct label *label; > + u64 objrevokeflags = 0; > + int rc = 0, pseries_status = 0; > + > + if (!var->name || !*var->name) { same comment as above > + pr_err("key label cannot be NULL/empty\n"); > + rc = -EINVAL; > + goto out; > + } > + > + if (!strcmp((char *)var->name, PLPKS_DEFAULT_WRAPKEY_LABEL)) { > + pr_warn("unrevoke on the default wrapping key is invalid\n"); > + rc = -EINVAL; > + goto out; > + } > + > + auth = construct_auth(PLPKS_OS_OWNER); > + if (IS_ERR(auth)) { > + rc = PTR_ERR(auth); > + goto out; > + } > + > + label = construct_label(var->component, var->os, var->name, > + var->namelen); > + if (IS_ERR(label)) { > + rc = PTR_ERR(label); > + goto out; > + } > + > + rc = plpar_hcall(H_PKS_UNREVOKE_OBJECT, retbuf, > + virt_to_phys(auth), virt_to_phys(label), > + label->size, objrevokeflags); > + > + pseries_status = rc; > + rc = pseries_status_to_err(rc); > + > + if (rc) > + pr_err("H_PKS_UNREVOKE_OBJECT failed. pseries_status=%d, rc=%d\n", > + pseries_status, rc); > + > + if (!rc || (rc == -EPERM && retbuf[0])) > + var->policy = (u32)retbuf[0]; > + > + kfree(label); > +out: > + kfree(auth); > + return rc; > +} > +EXPORT_SYMBOL_GPL(plpks_unrevoke_wrapping_key); > + > +/** > + * plpks_is_wrapping_key_revoked() - Check if a given wrapping key has been > + * revoked. > + * @var: variable representing the wrapping key to be checked > + * > + * When the H_PKS_READ_OBJECT HCALL tries reads an object that exists but when > + * the policy is not met, it returns H_AUTHORITY along with the 4-byte object > + * policy. This policy is inspected to determine if the object has been revoked. > + * > + * Possible reasons for the returned errno values: > + * > + * -ENXIO if PLPKS is not supported > + * -EIO if PLPKS access is blocked due to the LPAR's state > + * if an error occurred while processing the request > + * -EINVAL if invalid authorization parameter > + * if invalid object label parameter > + * if invalid object label len parameter > + * if invalid output data parameter > + * if invalid output data len parameter > + * -EPERM if access is denied > + * -ENOENT if the requested object was not found > + * -EFBIG if the requested object couldn't be > + * stored in the buffer provided > + * -EBUSY if unable to handle the request > + * > + * Returns: 1 is returned if the wrapping key has been revoked. 0 is returned if > + * the wrapping key has not been revoked. Otherwise, a negative errno > + * is returned. > + */ > +int plpks_is_wrapping_key_revoked(struct plpks_var *var) > +{ > + int rc; > + > + if (!var->name || !*var->name) { same comment as above > + pr_err("key label cannot be NULL/empty\n"); > + rc = -EINVAL; > + goto out; > + } > + > + rc = plpks_read_var(PLPKS_OS_OWNER, var); > + if (!rc) { > + pr_err("unexpected successful read of wrapping key\n"); > + rc = -EIO; > + } else if (rc == -EPERM) { > + if (var->policy & PLPKS_WRAPPINGKEY) { > + if (var->policy & PLPKS_REVOKED) > + rc = 1; > + else > + rc = 0; > + } > + } > + > +out: > + return rc; > +} > +EXPORT_SYMBOL_GPL(plpks_is_wrapping_key_revoked); > + > +/** > + * plpks_del_wrapping_key() - Delete a wrapping key from the PLPKS. > + * @var: variable representing the revoked wrapping key to be deleted > + * > + * The plpks_remove_var function removes the specified variable and its data > + * from the PLPKS by invoking the H_PKS_REMOVE_OBJECT HCALL. > + * > + * Possible reasons for the returned errno values: > + * > + * -ENXIO if PLPKS is not supported > + * -EIO if PLPKS access is blocked due to the LPAR's state > + * if PLPKS modification is blocked due to the LPAR's state > + * if an error occurred while processing the request > + * -EINVAL if invalid authorization parameter > + * if invalid object label parameter > + * if invalid object label len parameter > + * -EPERM if access is denied > + * -ENOENT if the requested object was not found > + * -EBUSY if unable to handle the request > + * > + * Returns: On success 0 is returned, a negative errno if not. > + */ > +int plpks_del_wrapping_key(struct plpks_var *var) > +{ > + int rc; > + struct plpks_var_name vname; > + > + if (!var->name || !*var->name) { same comment as above > + pr_err("key label cannot be NULL/empty\n"); > + rc = -EINVAL; > + goto out; > + } > + > + if (!strcmp((char *)var->name, PLPKS_DEFAULT_WRAPKEY_LABEL)) { > + pr_warn("the default wrapping key must not be deleted!\n"); > + rc = -EPERM; > + goto out; > + } > + > + rc = plpks_is_wrapping_key_revoked(var); > + if (rc == 1) { > + vname = (struct plpks_var_name) { > + .name = var->name, > + .namelen = var->namelen > + }; > + > + rc = plpks_remove_var(PLPKS_WRAPKEY_COMPONENT, var->os, > + vname); > + if (rc) > + pr_err("deletion of <%s> failed. rc=%d\n", > + (char *)var->name, rc); > + goto out; > + } else if (!rc) { > + pr_err("revoke <%s> before deletion\n", (char *)var->name); > + rc = -EPERM; > + goto out; > + } else { > + pr_err("revocation status check failed for <%s>. rc = %d\n", > + (char *)var->name, rc); > + } > + > +out: > + return rc; > +} > +EXPORT_SYMBOL_GPL(plpks_del_wrapping_key); > + > +/** > + * plpks_get_object_labels() - retrieve a list of object labels for the objects > + * stored in the PLPKS > + * @output_buf: buffer to store the retrieved object labels > + * @output_len: number of object labels retrieved > + * @comp_prefix: component prefix string > + * > + * The H_PKS_GET_OBJECTLABELS HCALL retrieves a list of object labels for the > + * objects with the given component prefix stored in the PLPKS. > + * > + * Possible reasons for the returned errno values: > + * > + * -ENXIO if PLPKS is not supported > + * -EIO if PLPKS access is blocked due to the LPAR's state > + * if PLPKS modification is blocked due to the LPAR's state > + * if an error occurred while processing the request > + * -EINVAL if invalid authorization parameter > + * if invalid output buffer parameter > + * if invalid output buffer length parameter > + * if invalid continue token parameter > + * if the provided component prefix is NULL > + * -EPERM if access is denied > + * -EBUSY if unable to handle the request or long running operation > + * initiated, retry later. > + * > + * Returns: On success 0 is returned, a negative errno if not. > + */ > +int plpks_get_object_labels(u8 **output_buf, u64 *output_len, > + char *comp_prefix) > +{ > + unsigned long retbuf[PLPAR_HCALL_BUFSIZE] = { 0 }; > + u8 *labels_buf = NULL; > + u8 *tmp_buf = NULL; > + struct plpks_auth *auth = NULL; > + struct label_attr *metadata = NULL; > + u16 label_len; > + u64 labels_count; > + u64 continuetoken = 0, output_buf_len = 0; > + int rc = 0, pseries_status = 0; > + size_t labels_buf_offset = 0, output_buf_offset = 0; > + size_t obj_label_entry_size, i; > + > + *output_buf = NULL; > + *output_len = 0; > + > + if (!comp_prefix) { > + rc = -EINVAL; > + goto out; > + } > + > + auth = construct_auth(PLPKS_OS_OWNER); > + if (IS_ERR(auth)) { > + rc = PTR_ERR(auth); > + goto out; > + } > + > + do { > + labels_buf = > + kzalloc(roundup_pow_of_two(PLPKS_OBJLABEL_BUF_MAX), > + GFP_KERNEL); > + > + if (!labels_buf) { > + pr_err("labels_buf buffer allocation failed\n"); > + rc = -ENOMEM; > + goto out_free_output_buf; > + } > + > + rc = plpar_hcall(H_PKS_GET_OBJECTLABELS, retbuf, > + virt_to_phys(auth), continuetoken, > + virt_to_phys(labels_buf), > + roundup_pow_of_two(PLPKS_OBJLABEL_BUF_MAX)); > + > + pseries_status = rc; > + rc = pseries_status_to_err(rc); > + > + if (rc && rc != -EAGAIN) { > + pr_err("H_PKS_GET_OBJECTLABELS failed. pseries_status=%d rc=%d\n", > + pseries_status, rc); > + goto out_free_labels_buf; > + } else { > + /* > + * Setting an incorrect countinuetoken upon > + * receiving H_CONTINUE would result in H_P2. Since > + * the continuetoken is being set to the expected > + * value from the previous call, H_P2 must not be > + * returned. > + */ > + continuetoken = retbuf[1]; > + > + labels_count = retbuf[0]; > + if (!labels_count) { > + kfree(labels_buf); > + labels_buf = NULL; > + goto out; > + } > + > + /* > + * Filter out object labels that don't have the provided > + * component prefix. > + */ > + > + output_buf_len += > + roundup_pow_of_two(PLPKS_OBJLABEL_BUF_MAX); > + > + tmp_buf = krealloc(*output_buf, output_buf_len, > + GFP_KERNEL); > + > + if (!tmp_buf) { > + pr_err("output buffer re-allocation failed\n"); > + rc = -ENOMEM; > + goto out_free_labels_buf; > + } > + > + *output_buf = tmp_buf; > + > + for (i = 0; i < labels_count; ++i) { > + label_len = > + get_unaligned_be16(labels_buf + > + labels_buf_offset); > + > + obj_label_entry_size = > + PLPKS_OBJLABEL_LEN_FIELD_SIZE + > + label_len; > + > + metadata = > + (struct label_attr *)(labels_buf + > + labels_buf_offset + > + PLPKS_OBJLABEL_LEN_FIELD_SIZE); > + > + if (!memcmp(metadata->prefix, comp_prefix, > + PLPKS_OBJLABEL_PREFIX_LEN)) { > + memcpy(*output_buf + output_buf_offset, > + labels_buf + labels_buf_offset, > + obj_label_entry_size); > + > + output_buf_offset += > + obj_label_entry_size; > + (*output_len) += 1; > + } > + labels_buf_offset += obj_label_entry_size; > + } > + kfree(labels_buf); > + labels_buf = NULL; > + labels_buf_offset = 0; > + } > + } while (rc == -EAGAIN); > + > + goto out; > + > +out_free_labels_buf: > + kfree(labels_buf); > + labels_buf = NULL; > +out_free_output_buf: > + kfree(*output_buf); > + *output_buf = NULL; > + *output_len = 0; > +out: > + kfree(auth); > + return rc; > +} > +EXPORT_SYMBOL_GPL(plpks_get_object_labels); > + > /** > * plpks_read_os_var() - Fetch the data for the specified variable that is owned > * by the OS consumer. -- Thanks and Regards R.Nageswara Sastry --------------CYnNj7x7LOdPK0GMFZH5FtBY Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: 8bit


On 27.08.2026 11:53 AM, Srish Srinivasan wrote:
The PKWM trusted source uses a single wrapping key per LPAR, created only
once during trust source initialization. All the wrap and unwrap requests
are bound to this default wrapping key.

Implement H_PKS_REVOKE_OBJECT, H_PKS_UNREVOKE_OBJECT, and
H_PKS_GET_OBJECTLABELS HCALLs to enable support for revoking and unrevoking
PKWM wrapping keys, and for retrieving wrapping key labels. The label
retrieval operation (H_PKS_GET_OBJECTLABELS) applies to all wrapping keys
including the default one, while the life cycle operations
(H_PKS_REVOKE_OBJECT/H_PKS_UNREVOKE_OBJECT) apply only to user-created
wrapping keys.

Signed-off-by: Srish Srinivasan <ssrish@linux.ibm.com>
---
 Documentation/arch/powerpc/papr_hcalls.rst |  33 ++
 arch/powerpc/include/asm/hvcall.h          |   5 +-
 arch/powerpc/include/asm/plpks.h           |  15 +
 arch/powerpc/platforms/pseries/plpks.c     | 475 ++++++++++++++++++++-
 4 files changed, 524 insertions(+), 4 deletions(-)

diff --git a/Documentation/arch/powerpc/papr_hcalls.rst b/Documentation/arch/powerpc/papr_hcalls.rst
index 44c9c8b32ae3..3455b403a048 100644
--- a/Documentation/arch/powerpc/papr_hcalls.rst
+++ b/Documentation/arch/powerpc/papr_hcalls.rst
@@ -343,6 +343,39 @@ is returned to the caller.
 H_PKS_UNWRAP_OBJECT is used to unwrap an object that was previously wrapped with
 H_PKS_WRAP_OBJECT.
 
+**H_PKS_REVOKE_OBJECT**
+
+| Input: authorization, objectlabel, objectlabellen, flags
+| Out: *object policy*
+| Return Value: *H_Success, H_Function, H_State, H_Parameter, H_P2, H_P3, H_P4,
+                H_Authority, H_Not_Found, H_Busy, H_Aborted*
+
+H_PKS_REVOKE_OBJECT is used to revoke an object in Platform Keystore.
+
+
+**H_PKS_UNREVOKE_OBJECT**
+
+| Input: authorization, objectlabel, objectlabellen, flags
+| Out: *object policy*
+| Return Value: *H_Success, H_Function, H_State, H_Parameter, H_P2, H_P3, H_P4,
+                H_Authority, H_Not_Found, H_Busy, H_Aborted*
+
+H_PKS_UNREVOKE_OBJECT is used to unrevoke an object that was previously revoked
+with H_PKS_REVOKE_OBJECT in Platform Keystore.
+
+
+**H_PKS_GET_OBJECTLABELS**
+
+| Input: authorization, continueToken, out, outlen
+| Out: *continue-token, number of object labels in the returned list, object
+        label list*
+| Return Value: *H_Success, H_Function, H_State, H_Parameter, H_P2, H_P3, H_P4,
+                H_Authority, H_Busy, H_Aborted, H_Continue*
+
+H_PKS_GET_OBJECTLABELS is used to retrieve a list of object labels owned by the
+specified consumer.
+
+
 References
 ==========
 .. [1] "Power Architecture Platform Reference"
diff --git a/arch/powerpc/include/asm/hvcall.h b/arch/powerpc/include/asm/hvcall.h
index dff90a7d7f70..4d4c2ce1dd87 100644
--- a/arch/powerpc/include/asm/hvcall.h
+++ b/arch/powerpc/include/asm/hvcall.h
@@ -340,6 +340,7 @@
 #define H_PKS_GET_CONFIG	0x41C
 #define H_PKS_SET_PASSWORD	0x420
 #define H_PKS_GEN_PASSWORD	0x424
+#define H_PKS_GET_OBJECTLABELS	0x428
 #define H_PKS_WRITE_OBJECT	0x42C
 #define H_PKS_GEN_KEY		0x430
 #define H_PKS_READ_OBJECT	0x434
@@ -362,7 +363,9 @@
 #define H_GUEST_DELETE		0x488
 #define H_PKS_WRAP_OBJECT	0x490
 #define H_PKS_UNWRAP_OBJECT	0x494
-#define MAX_HCALL_OPCODE	H_PKS_UNWRAP_OBJECT
+#define H_PKS_REVOKE_OBJECT	0x4AC
+#define H_PKS_UNREVOKE_OBJECT	0x4B0
+#define MAX_HCALL_OPCODE	H_PKS_UNREVOKE_OBJECT
 
 /* Scope args for H_SCM_UNBIND_ALL */
 #define H_UNBIND_SCOPE_ALL (0x1)
diff --git a/arch/powerpc/include/asm/plpks.h b/arch/powerpc/include/asm/plpks.h
index 8b2ffb27db5a..c39d1f07017e 100644
--- a/arch/powerpc/include/asm/plpks.h
+++ b/arch/powerpc/include/asm/plpks.h
@@ -25,6 +25,7 @@
 #define PLPKS_SIGNEDUPDATE	PPC_BIT32(7) // Object can only be modified by signed updates
 #define PLPKS_WRAPPINGKEY	PPC_BIT32(8) // Object contains a wrapping key
 #define PLPKS_HVPROVISIONED	PPC_BIT32(28) // Hypervisor has provisioned this object
+#define PLPKS_REVOKED		PPC_BIT32(30) // Object is revoked
 
 // Signature algorithm flags from signed_update_algorithms
 #define PLPKS_ALG_RSA2048	PPC_BIT(0)
@@ -123,6 +124,20 @@ int plpks_wrap_object(u8 **input_buf, u64 input_len, u16 wrap_flags,
 
 int plpks_unwrap_object(u8 **input_buf, u64 input_len,
 			u8 **output_buf, u64 *output_len);
+
+int plpks_revoke_wrapping_key(struct plpks_var *var);
+
+int plpks_unrevoke_wrapping_key(struct plpks_var *var);
+
+int plpks_del_wrapping_key(struct plpks_var *var);
+
+int plpks_is_wrapping_key_revoked(struct plpks_var *var);
+
+int plpks_get_object_labels(u8 **output_buf, u64 *output_len,
+			    char *comp_prefix);
+
+bool plpks_revoke_is_supported(void);
+
 #else // CONFIG_PSERIES_PLPKS
 static inline bool plpks_is_available(void) { return false; }
 static inline u16 plpks_get_passwordlen(void) { BUILD_BUG(); }
diff --git a/arch/powerpc/platforms/pseries/plpks.c b/arch/powerpc/platforms/pseries/plpks.c
index b553f7b130b6..48a86497eb2b 100644
--- a/arch/powerpc/platforms/pseries/plpks.c
+++ b/arch/powerpc/platforms/pseries/plpks.c
@@ -23,8 +23,17 @@
  */
 #define PLPKS_WRAPPING_BUF_DIFF	1024
 
+/*
+ * Maximum length for the buffer to store the retrieved object labels
+ */
+#define PLPKS_OBJLABEL_BUF_MAX	2550
+
+#define PLPKS_OBJLABEL_LEN_FIELD_SIZE	2
+#define PLPKS_OBJLABEL_PREFIX_LEN	8
+
 #define PLPKS_WRAP_INTERFACE_BIT	3
 #define PLPKS_WRAPPING_KEY_LENGTH	32
+#define PLPKS_REVOKE_INTERFACE_BIT	4
 
 #define WRAPFLAG_BE_BIT_SET(be_bit) \
 	BIT_ULL(63 - (be_bit))
@@ -46,6 +55,7 @@
 #include <linux/libfdt.h>
 #include <linux/memblock.h>
 #include <linux/bitfield.h>
+#include <linux/unaligned.h>
 #include <asm/hvcall.h>
 #include <asm/machdep.h>
 #include <asm/plpks.h>
@@ -67,6 +77,7 @@ static u32 maxlargeobjectsize;
 static u64 signedupdatealgorithms;
 static u64 wrappingfeatures;
 static bool wrapsupport;
+static bool revokesupport;
 
 struct plpks_auth {
 	u8 version;
@@ -146,6 +157,9 @@ static int pseries_status_to_err(int rc)
 	case H_ABORTED:
 		err = -EIO;
 		break;
+	case H_CONTINUE:
+		err = -EAGAIN;
+		break;
 	default:
 		err = -EINVAL;
 	}
@@ -312,6 +326,7 @@ static int _plpks_get_config(void)
 	signedupdatealgorithms = be64_to_cpu(config->signedupdatealgorithms);
 	wrappingfeatures = be64_to_cpu(config->wrappingfeatures);
 	wrapsupport = config->flags & PPC_BIT8(PLPKS_WRAP_INTERFACE_BIT);
+	revokesupport = config->flags & PPC_BIT8(PLPKS_REVOKE_INTERFACE_BIT);
 
 	// Validate that the numbers we get back match the requirements of the spec
 	if (maxpwsize < 32) {
@@ -831,9 +846,6 @@ static int plpks_read_var(u8 consumer, struct plpks_var *var)
 	if (var->namelen > PLPKS_MAX_NAME_SIZE)
 		return -EINVAL;
 
-	if (var->policy & PLPKS_WRAPPINGKEY)
-		return -EPERM;
-
 	auth = construct_auth(consumer);
 	if (IS_ERR(auth))
 		return PTR_ERR(auth);
@@ -903,6 +915,23 @@ bool plpks_wrapping_is_supported(void)
 }
 EXPORT_SYMBOL_GPL(plpks_wrapping_is_supported);
 
+/**
+ * plpks_revoke_is_supported() - Get the H_PKS_REVOKE_OBJECT and
+ * H_PKS_UNREVOKE_OBJECT interfaces availability status for the LPAR.
+ *
+ * Successful execution of the H_PKS_GET_CONFIG HCALL during initialization
+ * sets bit 4 of the flags variable in the PLPKS config structure if the
+ * H_PKS_REVOKE_OBJECT and H_PKS_UNREVOKE_OBJECT interfaces are supported.
+ *
+ * Returns: true if the H_PKS_REVOKE_OBJECT and H_PKS_UNREVOKE_OBJECT interfaces
+ * are supported, false if not.
+ */
+bool plpks_revoke_is_supported(void)
+{
+	return revokesupport;
+}
+EXPORT_SYMBOL_GPL(plpks_revoke_is_supported);
+
 /**
  * plpks_gen_wrapping_key() - Generate a new random key with the 'wrapping key'
  * policy set.
@@ -1189,6 +1218,446 @@ int plpks_unwrap_object(u8 **input_buf, u64 input_len, u8 **output_buf,
 }
 EXPORT_SYMBOL_GPL(plpks_unwrap_object);
 
+/**
+ * plpks_revoke_wrapping_key() - Revoke a wrapping key stored in the PLPKS.
+ * @var: variable representing the wrapping key to be revoked
+ *
+ * The H_PKS_REVOKE_OBJECT HCALL revokes an object stored in the PLPKS.
+ *
+ * Possible reasons for the returned errno values:
+ *
+ * -ENXIO	if PLPKS is not supported
+ * -EIO		if PLPKS access is blocked due to the LPAR's state
+ *		if PLPKS modification is blocked due to the LPAR's state
+ *		if an error occurred while processing the request
+ * -EINVAL	if invalid authorization parameter
+ *		if invalid wrapping key label parameter
+ *		if invalid wrapping key label length parameter
+ *		if invalid or unsupported wrapping key revoking flags
+ * -EPERM	if access is denied
+ * -ENOENT	if the requested wrapping key was not found
+ * -EBUSY	if unable to handle the request or long running operation
+ *		initiated, retry later.
+ *
+ * Returns: On success 0 is returned, a negative errno if not.
+ */
+int plpks_revoke_wrapping_key(struct plpks_var *var)
+{
+	unsigned long retbuf[PLPAR_HCALL_BUFSIZE] = { 0 };
+	struct plpks_auth *auth = NULL;
+	struct label *label;
+	u64 objrevokeflags = 0;
+	int rc = 0, pseries_status = 0;
+
+	if (!var->name || !*var->name) {

Can you please add null check for 'var' also.

if (! var || !var->name || !*var->name)

+		pr_err("key label cannot be NULL/empty\n");
+		rc = -EINVAL;
+		goto out;
+	}
+
+	if (!strcmp((char *)var->name, PLPKS_DEFAULT_WRAPKEY_LABEL)) {
+		pr_warn("the default wrapping key must not be revoked!\n");
+		rc = -EPERM;
+		goto out;
+	}
+
+	auth = construct_auth(PLPKS_OS_OWNER);
+	if (IS_ERR(auth)) {
+		rc = PTR_ERR(auth);
+		goto out;
+	}
+
+	label = construct_label(var->component, var->os, var->name,
+				var->namelen);
+	if (IS_ERR(label)) {
+		rc = PTR_ERR(label);
+		goto out;
+	}
+
+	rc = plpar_hcall(H_PKS_REVOKE_OBJECT, retbuf, virt_to_phys(auth),
+			 virt_to_phys(label), label->size, objrevokeflags);
+
+	pseries_status = rc;
+	rc = pseries_status_to_err(rc);
+
+	if (rc) {
+		pr_err("H_PKS_REVOKE_OBJECT failed. pseries_status=%d, rc=%d\n",
+		       pseries_status, rc);
+	}
+
+	if (!rc || (rc == -EPERM && retbuf[0]))
+		var->policy = (u32)retbuf[0];
+
+	kfree(label);
+out:
+	kfree(auth);
+	return rc;
+}
+EXPORT_SYMBOL_GPL(plpks_revoke_wrapping_key);
+
+/**
+ * plpks_unrevoke_wrapping_key() - Unrevoke a revoked wrapping key in the PLPKS.
+ * @var: variable representing the revoked wrapping key to be unrevoked
+ *
+ * The H_PKS_UNREVOKE_OBJECT HCALL unrevokes a revoked object stored in the
+ * PLPKS.
+ *
+ * Possible reasons for the returned errno values:
+ *
+ * -ENXIO	if PLPKS is not supported
+ * -EIO		if PLPKS access is blocked due to the LPAR's state
+ *		if PLPKS modification is blocked due to the LPAR's state
+ *		if an error occurred while processing the request
+ * -EINVAL	if invalid authorization parameter
+ *		if invalid object label parameter
+ *		if invalid object label length parameter
+ *		if invalid or unsupported object revoking flags
+ * -EPERM	if access is denied
+ * -ENOENT	if the requested object was not found
+ * -EBUSY	if unable to handle the request or long running operation
+ *		initiated, retry later.
+ *
+ * Returns: On success 0 is returned, a negative errno if not.
+ */
+int plpks_unrevoke_wrapping_key(struct plpks_var *var)
+{
+	unsigned long retbuf[PLPAR_HCALL_BUFSIZE] = { 0 };
+	struct plpks_auth *auth = NULL;
+	struct label *label;
+	u64 objrevokeflags = 0;
+	int rc = 0, pseries_status = 0;
+
+	if (!var->name || !*var->name) {
same comment as above 
+		pr_err("key label cannot be NULL/empty\n");
+		rc = -EINVAL;
+		goto out;
+	}
+
+	if (!strcmp((char *)var->name, PLPKS_DEFAULT_WRAPKEY_LABEL)) {
+		pr_warn("unrevoke on the default wrapping key is invalid\n");
+		rc = -EINVAL;
+		goto out;
+	}
+
+	auth = construct_auth(PLPKS_OS_OWNER);
+	if (IS_ERR(auth)) {
+		rc = PTR_ERR(auth);
+		goto out;
+	}
+
+	label = construct_label(var->component, var->os, var->name,
+				var->namelen);
+	if (IS_ERR(label)) {
+		rc = PTR_ERR(label);
+		goto out;
+	}
+
+	rc = plpar_hcall(H_PKS_UNREVOKE_OBJECT, retbuf,
+			 virt_to_phys(auth), virt_to_phys(label),
+			 label->size, objrevokeflags);
+
+	pseries_status = rc;
+	rc = pseries_status_to_err(rc);
+
+	if (rc)
+		pr_err("H_PKS_UNREVOKE_OBJECT failed. pseries_status=%d, rc=%d\n",
+		       pseries_status, rc);
+
+	if (!rc || (rc == -EPERM && retbuf[0]))
+		var->policy = (u32)retbuf[0];
+
+	kfree(label);
+out:
+	kfree(auth);
+	return rc;
+}
+EXPORT_SYMBOL_GPL(plpks_unrevoke_wrapping_key);
+
+/**
+ * plpks_is_wrapping_key_revoked() - Check if a given wrapping key has been
+ * revoked.
+ * @var: variable representing the wrapping key to be checked
+ *
+ * When the H_PKS_READ_OBJECT HCALL tries reads an object that exists but when
+ * the policy is not met, it returns H_AUTHORITY along with the 4-byte object
+ * policy. This policy is inspected to determine if the object has been revoked.
+ *
+ * Possible reasons for the returned errno values:
+ *
+ * -ENXIO	if PLPKS is not supported
+ * -EIO		if PLPKS access is blocked due to the LPAR's state
+ *		if an error occurred while processing the request
+ * -EINVAL	if invalid authorization parameter
+ *		if invalid object label parameter
+ *		if invalid object label len parameter
+ *		if invalid output data parameter
+ *		if invalid output data len parameter
+ * -EPERM	if access is denied
+ * -ENOENT	if the requested object was not found
+ * -EFBIG	if the requested object couldn't be
+ *		stored in the buffer provided
+ * -EBUSY	if unable to handle the request
+ *
+ * Returns: 1 is returned if the wrapping key has been revoked. 0 is returned if
+ *	    the wrapping key has not been revoked. Otherwise, a negative errno
+ *	    is returned.
+ */
+int plpks_is_wrapping_key_revoked(struct plpks_var *var)
+{
+	int rc;
+
+	if (!var->name || !*var->name) {
same comment as above 
+		pr_err("key label cannot be NULL/empty\n");
+		rc = -EINVAL;
+		goto out;
+	}
+
+	rc = plpks_read_var(PLPKS_OS_OWNER, var);
+	if (!rc) {
+		pr_err("unexpected successful read of wrapping key\n");
+		rc = -EIO;
+	} else if (rc == -EPERM) {
+		if (var->policy & PLPKS_WRAPPINGKEY) {
+			if (var->policy & PLPKS_REVOKED)
+				rc = 1;
+			else
+				rc = 0;
+		}
+	}
+
+out:
+	return rc;
+}
+EXPORT_SYMBOL_GPL(plpks_is_wrapping_key_revoked);
+
+/**
+ * plpks_del_wrapping_key() - Delete a wrapping key from the PLPKS.
+ * @var: variable representing the revoked wrapping key to be deleted
+ *
+ * The plpks_remove_var function removes the specified variable and its data
+ * from the PLPKS by invoking the H_PKS_REMOVE_OBJECT HCALL.
+ *
+ * Possible reasons for the returned errno values:
+ *
+ * -ENXIO	if PLPKS is not supported
+ * -EIO		if PLPKS access is blocked due to the LPAR's state
+ *		if PLPKS modification is blocked due to the LPAR's state
+ *		if an error occurred while processing the request
+ * -EINVAL	if invalid authorization parameter
+ *		if invalid object label parameter
+ *		if invalid object label len parameter
+ * -EPERM	if access is denied
+ * -ENOENT	if the requested object was not found
+ * -EBUSY	if unable to handle the request
+ *
+ * Returns: On success 0 is returned, a negative errno if not.
+ */
+int plpks_del_wrapping_key(struct plpks_var *var)
+{
+	int rc;
+	struct plpks_var_name vname;
+
+	if (!var->name || !*var->name) {
same comment as above 
+		pr_err("key label cannot be NULL/empty\n");
+		rc = -EINVAL;
+		goto out;
+	}
+
+	if (!strcmp((char *)var->name, PLPKS_DEFAULT_WRAPKEY_LABEL)) {
+		pr_warn("the default wrapping key must not be deleted!\n");
+		rc = -EPERM;
+		goto out;
+	}
+
+	rc = plpks_is_wrapping_key_revoked(var);
+	if (rc == 1) {
+		vname = (struct plpks_var_name) {
+			.name = var->name,
+			.namelen = var->namelen
+		};
+
+		rc = plpks_remove_var(PLPKS_WRAPKEY_COMPONENT, var->os,
+				      vname);
+		if (rc)
+			pr_err("deletion of <%s> failed. rc=%d\n",
+			       (char *)var->name, rc);
+		goto out;
+	} else if (!rc) {
+		pr_err("revoke <%s> before deletion\n", (char *)var->name);
+		rc = -EPERM;
+		goto out;
+	} else {
+		pr_err("revocation status check failed for <%s>. rc = %d\n",
+		       (char *)var->name, rc);
+	}
+
+out:
+	return rc;
+}
+EXPORT_SYMBOL_GPL(plpks_del_wrapping_key);
+
+/**
+ * plpks_get_object_labels() - retrieve a list of object labels for the objects
+ * stored in the PLPKS
+ * @output_buf: buffer to store the retrieved object labels
+ * @output_len: number of object labels retrieved
+ * @comp_prefix: component prefix string
+ *
+ * The H_PKS_GET_OBJECTLABELS HCALL retrieves a list of object labels for the
+ * objects with the given component prefix stored in the PLPKS.
+ *
+ * Possible reasons for the returned errno values:
+ *
+ * -ENXIO	if PLPKS is not supported
+ * -EIO		if PLPKS access is blocked due to the LPAR's state
+ *		if PLPKS modification is blocked due to the LPAR's state
+ *		if an error occurred while processing the request
+ * -EINVAL	if invalid authorization parameter
+ *		if invalid output buffer parameter
+ *		if invalid output buffer length parameter
+ *		if invalid continue token parameter
+ *		if the provided component prefix is NULL
+ * -EPERM	if access is denied
+ * -EBUSY	if unable to handle the request or long running operation
+ *		initiated, retry later.
+ *
+ * Returns: On success 0 is returned, a negative errno if not.
+ */
+int plpks_get_object_labels(u8 **output_buf, u64 *output_len,
+			    char *comp_prefix)
+{
+	unsigned long retbuf[PLPAR_HCALL_BUFSIZE] = { 0 };
+	u8 *labels_buf = NULL;
+	u8 *tmp_buf = NULL;
+	struct plpks_auth *auth = NULL;
+	struct label_attr *metadata = NULL;
+	u16 label_len;
+	u64 labels_count;
+	u64 continuetoken = 0, output_buf_len = 0;
+	int rc = 0, pseries_status = 0;
+	size_t labels_buf_offset = 0, output_buf_offset = 0;
+	size_t obj_label_entry_size, i;
+
+	*output_buf = NULL;
+	*output_len = 0;
+
+	if (!comp_prefix) {
+		rc = -EINVAL;
+		goto out;
+	}
+
+	auth = construct_auth(PLPKS_OS_OWNER);
+	if (IS_ERR(auth)) {
+		rc = PTR_ERR(auth);
+		goto out;
+	}
+
+	do {
+		labels_buf =
+			kzalloc(roundup_pow_of_two(PLPKS_OBJLABEL_BUF_MAX),
+				GFP_KERNEL);
+
+		if (!labels_buf) {
+			pr_err("labels_buf buffer allocation failed\n");
+			rc = -ENOMEM;
+			goto out_free_output_buf;
+		}
+
+		rc = plpar_hcall(H_PKS_GET_OBJECTLABELS, retbuf,
+				 virt_to_phys(auth), continuetoken,
+				 virt_to_phys(labels_buf),
+				 roundup_pow_of_two(PLPKS_OBJLABEL_BUF_MAX));
+
+		pseries_status = rc;
+		rc = pseries_status_to_err(rc);
+
+		if (rc && rc != -EAGAIN) {
+			pr_err("H_PKS_GET_OBJECTLABELS failed. pseries_status=%d rc=%d\n",
+			       pseries_status, rc);
+			goto out_free_labels_buf;
+		} else {
+			/*
+			 * Setting an incorrect countinuetoken upon
+			 * receiving H_CONTINUE would result in H_P2. Since
+			 * the continuetoken is being set to the expected
+			 * value from the previous call, H_P2 must not be
+			 * returned.
+			 */
+			continuetoken = retbuf[1];
+
+			labels_count = retbuf[0];
+			if (!labels_count) {
+				kfree(labels_buf);
+				labels_buf = NULL;
+				goto out;
+			}
+
+			/*
+			 * Filter out object labels that don't have the provided
+			 * component prefix.
+			 */
+
+			output_buf_len +=
+				roundup_pow_of_two(PLPKS_OBJLABEL_BUF_MAX);
+
+			tmp_buf = krealloc(*output_buf, output_buf_len,
+					   GFP_KERNEL);
+
+			if (!tmp_buf) {
+				pr_err("output buffer re-allocation failed\n");
+				rc = -ENOMEM;
+				goto out_free_labels_buf;
+			}
+
+			*output_buf = tmp_buf;
+
+			for (i = 0; i < labels_count; ++i) {
+				label_len =
+					get_unaligned_be16(labels_buf +
+							   labels_buf_offset);
+
+				obj_label_entry_size =
+					PLPKS_OBJLABEL_LEN_FIELD_SIZE +
+					label_len;
+
+				metadata =
+					(struct label_attr *)(labels_buf +
+					labels_buf_offset +
+					PLPKS_OBJLABEL_LEN_FIELD_SIZE);
+
+				if (!memcmp(metadata->prefix, comp_prefix,
+					    PLPKS_OBJLABEL_PREFIX_LEN)) {
+					memcpy(*output_buf + output_buf_offset,
+					       labels_buf + labels_buf_offset,
+					       obj_label_entry_size);
+
+					output_buf_offset +=
+						obj_label_entry_size;
+					(*output_len) += 1;
+				}
+				labels_buf_offset += obj_label_entry_size;
+			}
+			kfree(labels_buf);
+			labels_buf = NULL;
+			labels_buf_offset = 0;
+		}
+	} while (rc == -EAGAIN);
+
+	goto out;
+
+out_free_labels_buf:
+	kfree(labels_buf);
+	labels_buf = NULL;
+out_free_output_buf:
+	kfree(*output_buf);
+	*output_buf = NULL;
+	*output_len = 0;
+out:
+	kfree(auth);
+	return rc;
+}
+EXPORT_SYMBOL_GPL(plpks_get_object_labels);
+
 /**
  * plpks_read_os_var() - Fetch the data for the specified variable that is owned
  * by the OS consumer.

-- 
Thanks and Regards
R.Nageswara Sastry
--------------CYnNj7x7LOdPK0GMFZH5FtBY--