hrev53522 adds 1 changeset to branch 'master'
old head: d19c9471b16dfe6f7bf2d03525b0bc95080f6c03
new head: 9268c3d7e5b6af830631b237ef55fa4baadf3b01
overview:
https://git.haiku-os.org/haiku/log/?qt=range&q=9268c3d7e5b6+%5Ed19c9471b16d
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9268c3d7e5b6: x86: Reorder ifs in page fault handler
* If interrupts were disabled, SMAP and SMEP violation message was
shadowed by confusing "page fault but interrupts disabled" panic.
Change-Id: I7470329984e55330f35fdca9b7c253fc4684e0c8
Reviewed-on: https://review.haiku-os.org/c/haiku/+/1891
Reviewed-by: waddlesplash <waddlesplash@xxxxxxxxx>
Reviewed-by: Adrien Destugues <pulkomandy@xxxxxxxxx>
[ Kacper Kasper <kacperkasper@xxxxxxxxx> ]
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Revision: hrev53522
Commit: 9268c3d7e5b6af830631b237ef55fa4baadf3b01
URL: https://git.haiku-os.org/haiku/commit/?id=9268c3d7e5b6
Author: Kacper Kasper <kacperkasper@xxxxxxxxx>
Date: Fri Sep 27 20:24:49 2019 UTC
Committer: waddlesplash <waddlesplash@xxxxxxxxx>
Commit-Date: Tue Oct 1 02:50:14 2019 UTC
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1 file changed, 15 insertions(+), 15 deletions(-)
src/system/kernel/arch/x86/arch_int.cpp | 30 ++++++++++++++---------------
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diff --git a/src/system/kernel/arch/x86/arch_int.cpp
b/src/system/kernel/arch/x86/arch_int.cpp
index 5588d5d181..416e9d21c4 100644
--- a/src/system/kernel/arch/x86/arch_int.cpp
+++ b/src/system/kernel/arch/x86/arch_int.cpp
@@ -296,6 +296,21 @@ x86_page_fault_exception(struct iframe* frame)
panic("page fault in debugger without fault handler! Touching "
"address %p from ip %p\n", (void*)cr2,
(void*)frame->ip);
return;
+ } else if (!IFRAME_IS_USER(frame)
+ && (frame->error_code & PGFAULT_I) != 0
+ && (x86_read_cr4() & IA32_CR4_SMEP) != 0) {
+ // check that: 1. come not from userland,
+ // 2. is an instruction fetch, 3. smep is enabled
+ panic("SMEP violation user-mapped address %p touched from
kernel %p\n",
+ (void*)cr2, (void*)frame->ip);
+ } else if ((frame->flags & X86_EFLAGS_ALIGNMENT_CHECK) == 0
+ && !IFRAME_IS_USER(frame)
+ && (frame->error_code & PGFAULT_P) != 0
+ && (x86_read_cr4() & IA32_CR4_SMAP) != 0) {
+ // check that: 1. AC flag is not set, 2. come not from userland,
+ // 3. is a page-protection violation, 4. smap is enabled
+ panic("SMAP violation user-mapped address %p touched from
kernel %p\n",
+ (void*)cr2, (void*)frame->ip);
} else if ((frame->flags & X86_EFLAGS_INTERRUPT) == 0) {
// interrupts disabled
@@ -327,21 +342,6 @@ x86_page_fault_exception(struct iframe* frame)
panic("page fault not allowed at this place. Touching address "
"%p from ip %p\n", (void*)cr2, (void*)frame->ip);
return;
- } else if (!IFRAME_IS_USER(frame)
- && (frame->error_code & PGFAULT_I) != 0
- && (x86_read_cr4() & IA32_CR4_SMEP) != 0) {
- // check that: 1. come not from userland,
- // 2. is an instruction fetch, 3. smep is enabled
- panic("SMEP violation user-mapped address %p touched from
kernel %p\n",
- (void*)cr2, (void*)frame->ip);
- } else if ((frame->flags & X86_EFLAGS_ALIGNMENT_CHECK) == 0
- && !IFRAME_IS_USER(frame)
- && (frame->error_code & PGFAULT_P) != 0
- && (x86_read_cr4() & IA32_CR4_SMAP) != 0) {
- // check that: 1. AC flag is not set, 2. come not from userland,
- // 3. is a page-protection violation, 4. smap is enabled
- panic("SMAP violation user-mapped address %p touched from
kernel %p\n",
- (void*)cr2, (void*)frame->ip);
}
enable_interrupts();
