summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorThiago Jung Bauermann <bauerman@linux.ibm.com>2019-08-06 01:49:18 -0300
committerMichael Ellerman <mpe@ellerman.id.au>2019-08-09 22:52:10 +1000
commitae7eb82a92fae4d255a0caa9f7c0f99e3babfec1 (patch)
tree437ed5313f25e22610f994171ecc7a355ba62590
parent284e21fab2cfcf90dacce565e0b12f29e5df00c1 (diff)
fs/core/vmcore: Move sev_active() reference to x86 arch code
Secure Encrypted Virtualization is an x86-specific feature, so it shouldn't appear in generic kernel code because it forces non-x86 architectures to define the sev_active() function, which doesn't make a lot of sense. To solve this problem, add an x86 elfcorehdr_read() function to override the generic weak implementation. To do that, it's necessary to make read_from_oldmem() public so that it can be used outside of vmcore.c. Also, remove the export for sev_active() since it's only used in files that won't be built as modules. Signed-off-by: Thiago Jung Bauermann <bauerman@linux.ibm.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Lianbo Jiang <lijiang@redhat.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190806044919.10622-6-bauerman@linux.ibm.com
-rw-r--r--arch/x86/kernel/crash_dump_64.c5
-rw-r--r--arch/x86/mm/mem_encrypt.c1
-rw-r--r--fs/proc/vmcore.c8
-rw-r--r--include/linux/crash_dump.h14
-rw-r--r--include/linux/mem_encrypt.h1
5 files changed, 23 insertions, 6 deletions
diff --git a/arch/x86/kernel/crash_dump_64.c b/arch/x86/kernel/crash_dump_64.c
index 22369dd5de3b..045e82e8945b 100644
--- a/arch/x86/kernel/crash_dump_64.c
+++ b/arch/x86/kernel/crash_dump_64.c
@@ -70,3 +70,8 @@ ssize_t copy_oldmem_page_encrypted(unsigned long pfn, char *buf, size_t csize,
{
return __copy_oldmem_page(pfn, buf, csize, offset, userbuf, true);
}
+
+ssize_t elfcorehdr_read(char *buf, size_t count, u64 *ppos)
+{
+ return read_from_oldmem(buf, count, ppos, 0, sev_active());
+}
diff --git a/arch/x86/mm/mem_encrypt.c b/arch/x86/mm/mem_encrypt.c
index 94da5a88abe6..9268c12458c8 100644
--- a/arch/x86/mm/mem_encrypt.c
+++ b/arch/x86/mm/mem_encrypt.c
@@ -349,7 +349,6 @@ bool sev_active(void)
{
return sme_me_mask && sev_enabled;
}
-EXPORT_SYMBOL(sev_active);
/* Override for DMA direct allocation check - ARCH_HAS_FORCE_DMA_UNENCRYPTED */
bool force_dma_unencrypted(struct device *dev)
diff --git a/fs/proc/vmcore.c b/fs/proc/vmcore.c
index 7bcc92add72c..7b13988796e1 100644
--- a/fs/proc/vmcore.c
+++ b/fs/proc/vmcore.c
@@ -104,9 +104,9 @@ static int pfn_is_ram(unsigned long pfn)
}
/* Reads a page from the oldmem device from given offset. */
-static ssize_t read_from_oldmem(char *buf, size_t count,
- u64 *ppos, int userbuf,
- bool encrypted)
+ssize_t read_from_oldmem(char *buf, size_t count,
+ u64 *ppos, int userbuf,
+ bool encrypted)
{
unsigned long pfn, offset;
size_t nr_bytes;
@@ -170,7 +170,7 @@ void __weak elfcorehdr_free(unsigned long long addr)
*/
ssize_t __weak elfcorehdr_read(char *buf, size_t count, u64 *ppos)
{
- return read_from_oldmem(buf, count, ppos, 0, sev_active());
+ return read_from_oldmem(buf, count, ppos, 0, false);
}
/*
diff --git a/include/linux/crash_dump.h b/include/linux/crash_dump.h
index f774c5eb9e3c..4664fc1871de 100644
--- a/include/linux/crash_dump.h
+++ b/include/linux/crash_dump.h
@@ -115,4 +115,18 @@ static inline int vmcore_add_device_dump(struct vmcoredd_data *data)
return -EOPNOTSUPP;
}
#endif /* CONFIG_PROC_VMCORE_DEVICE_DUMP */
+
+#ifdef CONFIG_PROC_VMCORE
+ssize_t read_from_oldmem(char *buf, size_t count,
+ u64 *ppos, int userbuf,
+ bool encrypted);
+#else
+static inline ssize_t read_from_oldmem(char *buf, size_t count,
+ u64 *ppos, int userbuf,
+ bool encrypted)
+{
+ return -EOPNOTSUPP;
+}
+#endif /* CONFIG_PROC_VMCORE */
+
#endif /* LINUX_CRASHDUMP_H */
diff --git a/include/linux/mem_encrypt.h b/include/linux/mem_encrypt.h
index 0c5b0ff9eb29..5c4a18a91f89 100644
--- a/include/linux/mem_encrypt.h
+++ b/include/linux/mem_encrypt.h
@@ -19,7 +19,6 @@
#else /* !CONFIG_ARCH_HAS_MEM_ENCRYPT */
static inline bool mem_encrypt_active(void) { return false; }
-static inline bool sev_active(void) { return false; }
#endif /* CONFIG_ARCH_HAS_MEM_ENCRYPT */