diff options
| author |   Russell King <rmk+kernel@armlinux.org.uk> | 2016-05-13 11:40:20 +0100 |
|---|---|---|
| committer | Russell King <rmk+kernel@armlinux.org.uk> | 2016-07-07 16:01:01 +0100 |
| commit | e6978e4bf181fb3b5f8cb6f71b4fe30fbf1b655c (patch) | |
| tree | dddb20dbc9a5e594e406e71ed598039b33e0a4be /arch/arm/kernel/process.c | |
| parent | ARM: 8584/1: floppy: avoid gcc-6 warning (diff) | |
| download | linux-dev-e6978e4bf181fb3b5f8cb6f71b4fe30fbf1b655c.tar.xz linux-dev-e6978e4bf181fb3b5f8cb6f71b4fe30fbf1b655c.zip | |
ARM: save and reset the address limit when entering an exception
When we enter an exception, the current address limit should not apply
to the exception context: if the exception context wishes to access
kernel space via the user accessors (eg, perf code), it must explicitly
request such access.
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Diffstat (limited to 'arch/arm/kernel/process.c')
| -rw-r--r-- | arch/arm/kernel/process.c | 12 |
1 files changed, 8 insertions, 4 deletions
diff --git a/arch/arm/kernel/process.c b/arch/arm/kernel/process.c index f1c720c0d568..612eb530f33f 100644 --- a/arch/arm/kernel/process.c +++ b/arch/arm/kernel/process.c @@ -96,19 +96,23 @@ void __show_regs(struct pt_regs *regs) unsigned long flags; char buf[64]; #ifndef CONFIG_CPU_V7M - unsigned int domain; + unsigned int domain, fs; #ifdef CONFIG_CPU_SW_DOMAIN_PAN /* * Get the domain register for the parent context. In user * mode, we don't save the DACR, so lets use what it should * be. For other modes, we place it after the pt_regs struct. */ - if (user_mode(regs)) + if (user_mode(regs)) { domain = DACR_UACCESS_ENABLE; - else + fs = get_fs(); + } else { domain = to_svc_pt_regs(regs)->dacr; + fs = to_svc_pt_regs(regs)->addr_limit; + } #else domain = get_domain(); + fs = get_fs(); #endif #endif @@ -144,7 +148,7 @@ void __show_regs(struct pt_regs *regs) if ((domain & domain_mask(DOMAIN_USER)) == domain_val(DOMAIN_USER, DOMAIN_NOACCESS)) segment = "none"; - else if (get_fs() == get_ds()) + else if (fs == get_ds()) segment = "kernel"; else segment = "user"; |